Research team

Sustainable Energy, Air and Water Technology (DuEL)

Expertise

The central research theme is solar photochemistry for energy and environmental applications. An important line of research in that regards is pllasmonic photocatalysis. By maintaining a holistic bottom-up approach, every aspect of this research theme is addressed. The main focus is on the fundamental level of surface science (catalyst synthesis, surface modification (coatings), morphological engineering, modeling of the light-matter interaction, etc.), but other aspects such as reactor design, activity testing, social and economic aspects are elaborately addressed as well. The main research goal is to boost the photocatalytic activity of metal oxide semiconductors by improving their solar light conversion efficiency and photon utilization capacity. One of the primary strategies is surface modification with plasmonic nanostructures. A thorough fundamental mechanistic understanding of these composite nanomaterials is key, and will in time lead to more performant applications. A second line of research involves the application of photocatalysis in various fields: air purification, degradation of soot / particulate matter, self-cleaning and super-hydrophilic surfaces, and photo-electrochemical cells that couple air purification to hydrogen gas production.

True colours of titanium dioxide - coloured titania and their advanced characterisation for use in CO2 reduction and sensing applications 01/01/2021 - 31/12/2024

Abstract

Titanium-dioxide-based materials (titania) are semiconductors with many versatile applications in chemical catalysis, electrochemical sensing, food industry, energy conversion and many more. A considerable part of these applications rely on the electron-hole formation in titania by the absorption of light in the UV range. However, this restricts many practical applications, since sunlight has a limited UV content. Coloured titania, such as grey and black titania, can be formed via thermal, chemical or sonochemical reduction pathways. Although these materials absorb light in the visible range, there is many conflicting data reported about their activity and involved mechanistic pathways. There is also no consensus on the optimal synthesis routes to enhance specific favorable material characteristics. The large heterogeneity in coloured titania materials and their syntheses used in literature hampers a clear correlation between synthesis, electronic structure and activity. In this concerted action, we aim at a controlled alteration of the reduction conditions of porous titania linked to a direct determination of a variety of properties, such as electron traps, surface-adsorbed and surface-reacted species, bulk defects, band gap, polymorphs and pore sizes, and to activity measurements. For the latter we will test their capacity for photocatalytic reduction of CO2 and their applicability as electrode material in the electrochemical sensing of phenolic compounds in water. With this approach we guarantee that the results of the different experiments can be directly compared and correlated. This will allow determining the key factors governing the relation between synthesis, electronic and geometric structure and activity of coloured titania. This knowledge will be translated in optimal synthesis conditions for the here proposed applications, of importance in sustainable chemistry and development. The project makes use of the unique complementary expertise in the synthesis, experimental and theoretical characterization and application of titanium-dioxide-based materials available at UAntwerp.

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Zinc-co-Sink, dual pathway for safe rubber granulate recycling. 01/01/2021 - 31/12/2022

Abstract

This project is being carried out by the University of Antwerp and VITO, and supported by the Belgian Road Research Centre (BRRC). Two possible solutions are being investigated to prevent the release of zinc from rubber granules; on the one hand by coating the rubber granules (UAntwerp) and on the other hand by trapping the released harmful components in a sorbent before they are released into the environment (VITO). The first phase of the research consists of a feasibility study into the most suitable solution for using unbound rubber granules in sonic crystals (for the Rubsonik project, led by BRRC). Possible solutions can, however, be developed further at a later stage (phase II) and can also be used for other applications of rubber granulates where environmental problems play a role. In the follow-up research, attention will also be paid to the recyclability and durability of both solutions (influence of ageing and/or exceptional weather conditions).

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Covalent Organic Frameworks: Electrodes for Photoelectrocatalytic Conversion of Carbon Dioxide and VOCs into Ecofriendly Fuels. 01/11/2020 - 31/10/2023

Abstract

The two biggest challenges of the 21st century are: i) air pollution and global warming, and ii) seeking alternative energy sources. To address both these issues, we plan to combine air-treatment with generation of green energy/chemicals as end products, using solar power. In particular, we will focus on photoelectrocatalytic decomposition of volatile organic compounds (VOCs) and CO2 to produce hydrogen and formic acid respectively. The efficiency of these reactions is limited with conventionally used aqueous phase with TiO2 or noble metal-based electrodes. We propose to overcome these issues by running a gas phase photoelectrocatalytic cell by metal-free, highly porous and electrochemically stable photoelectrodes. In that context, we will explore the possibility of using Covalent Organic Frameworks (COF) as photoelectrodes. Apart from their high surface area and tunable bandgap, the metal-free COFs are cheap and devoid of leaching. However, their low electrical conductivity presents a hurdle. Here, we will focus on enhancing the optical and electrical conductivity of COFs simultaneously by synthesizing highly conjugated COFs and growing them on carbon fibre cloth (CFC) as binder-free COF-CFC hybrid electrodes. Combining the expertise and facilities of COMOC (UGent) and DuEL groups (UAntwerpen), we plan to optimize the photoelectrochemical reactions with COF-based electrodes. Such optimizations will facilitate the future adoption of our work in a larger industrial setting.

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Plasmonic sensors for the sensitive and selective detection of volatile organic compounds; 01/11/2020 - 31/10/2022

Abstract

The quantitative detection of volatile organic compounds (VOCs) is an essential but challenging task with a broad range of applications: diagnosing disease via breath analysis, monitoring indoor air quality, checking food freshness, detecting explosives, etc. Because of the shortcomings of current gas sensors, the demand for a new generation of selective and sensitive VOC sensors is pressing. This PhD project targets a new type of spectroscopic sensors that tackle this challenge through the combination of (1) nanoscale engineering of light-matter interactions, (2) the growth of thin porous films with a high VOC adsorption affinity, and (3) a biomimetic method to leverage the combined data from an array of partially selective sensors. These concepts will be brought together for the first time through the close collaboration of researchers at two universities and will be demonstrated in the detection of three harmful VOCs in simulated indoor air.

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InSusChem - Consortium for Integrated Sustainable Chemistry Antwerp. 15/10/2020 - 31/12/2026

Abstract

This IOF consortium connects chemists, engineers, economic and environmental oriented researchers in an integrated team to maximize impact in key enabling sustainable chemical technologies, materials and reactors that are able to play a crucial role in a sustainable chemistry and economic transition to a circular, resource efficient and carbon neutral economy (part of the 2030 and 2050 goals in which Europe aims to lead). Innovative materials, renewable chemical feedstocks, new/alternative reactors, technologies and production methods are essential and central elements to achieve this goal. Due to their mutual interplay, a multidisciplinary, concerted effort is crucial to be successful. Furthermore, early on prediction and identification of strengths, opportunities, weaknesses and threats in life cycles, techno-economics and sustainability are key to allow sustainability by design and create effective knowledge-based decision-making and focus. The consortium focuses on sustainable chemical production through efficient and alternative energy use connected to circularity, new chemical pathways, technologies, reactors and materials, that allow the use of alternative feedstock and energy supply. These core technical aspects are supported by expertise in simulation, techno-economic and environmental impact assessment and uncertainty identification to accelerate technological development via knowledge-based design and early stage identified key research, needed for accelerated growth and maximum impact on sustainability. To achieve these goals, the consortium members are grouped in 4 interconnected valorisation programs focusing on key performance elements that thrive the chemical industry and technology: 1) renewable building blocks; 2) sustainable materials and materials for sustainable processes; 3) sustainable processes, efficiently using alternative renewable energy sources and/or circular chemical building blocks; 4) innovative reactors for sustainable processes. In addition, cross-cutting integrated enablers are present, providing expertise and essential support to the 4 valorisation programs through simulation, techno-economic and environmental impact assessment and uncertainty analysis.

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Photoelectrochemical abatement of methane waste with simultaneous energy recovery. 01/10/2020 - 30/09/2022

Abstract

Methane has recently been under attention as the atmospheric methane concentration is increasing more rapidly than initially expected. As methane is the second largest contributor to the enhanced greenhouse effect, this increases the urge for sustainable methane mitigation strategies in contrast to the current handling of methane emissions (e.g. venting). In this project a sustainable methane mitigation strategy, namely photoelectrochemical (PEC) methane degradation, is presented, which has not been studied before. In a PEC cell both mineralization of methane (at the photo-anode) and hydrogen evolution (at the cathode) are combined in a single device that runs solely on (solar) light as the energy input. First, the PEC cell will be optimized by selecting the best performing photo-anode material using the knowledge attained at the Wuhan University of Technology (China), also studying less conventional materials, nanostructures and synthesis strategies. As methane-rich waste streams are often gas mixtures, the influence of different common chemical compounds will be investigated both on overall cell performance, as well as in-situ. Finally, the effect of different reaction conditions will also be studied, as these factors are known to strongly influence photodriven processes. In summary, this project will allow us to evaluate the promise of PEC-technology for energy-efficient abatement of methane waste, while providing valuable new insight into the reaction mechanisms.

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Research team(s)

High resolution Raman spectroscopy and imaging. 01/05/2020 - 30/04/2024

Abstract

High resolution Raman imaging is a versatile imaging technique that generates detailed maps of the chemical composition of technical as well as biological samples. The equipment with given specifications is not yet available at UAntwerp, and will crucially complement the high-end chemical imaging techniques (XRF, XRD, IR, SEM-EDX-WDX, LA-ICP-MS) that are already available at UAntwerp for material characterization. High resolution Raman imaging will expose, with high resolution, the final details (structural fingerprint) of the material of interest. In first instance, we aim to boost the following research lines: electrochemistry, photocatalysis, marine microbiology, environmental analysis and cultural heritage. The Raman microscope should be as versatile as possible, to support potential future technological enhancements.

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Dioxide to monoxide (D2M): innovative catalysis for CO2 to CO conversion (D2M). 01/01/2020 - 30/09/2021

Abstract

The aim of this project is to study, explore and develop various (catalytic) technologies for the production of CO as platform chemical via conversion of CO2. A technology assessment will subsequently be carried out to evaluate the potential of each technology, pinpointing promising strategies for further development and upscaling. Concrete objectives and criteria The efficiency/productivity of existing homogeneous catalytic systems for CO2 reduction to CO will be mapped out and evaluated to identify the most promising systems to achieve this reduction and to explore ways to improve its larger scale viability through detailed catalyst modification studies. The focus will be on cobalt and nickel systems containing N-heterocyclic carbene (NHC) species as ligands. The goal of the heterogeneous catalytic conversion of CO2 to CO is to assess the potential of the oxidative propane dehydrogenation (OPD) reaction with CO2 as a soft oxidant. The main purpose here is to focus on and maximize CO2 reduction and CO formation via novel catalyst synthesis, surface engineering and investigation of catalyst support. In the field of electrocatalytic conversion of CO2 to CO we aim to (1) develop metal-based electrodes (electrocatalysts integrated in gas diffusion electrodes) exhibiting enhanced stability, (2) to investigate a novel type of metal-free electrocatalyst that can tackle the current challenges witnessed in N-doped carbons and (3) to demonstrate the continuous production of CO from CO2 by the development of a prototype lab scale reactor including the best-performing electrocatalysts developed in this project Another goal of this project is providing a proof-of-concept for plasmonic enhanced CO2 conversion into CO in an energy-lean process involving only solar light at ambient pressure as energy input i.e. without external heating. The objective of the plasma catalytic route for CO production is to enhance the conversion and energy efficiency of CO2 conversion in different plasma reactor types, with major focus on Gliding Arc plasma and Nanosecond pulsed discharges (NPD) plasma reactors. The project also takes up the challenge to activate CO2 and bio-CH4 and turn them into CO by combining chemical looping processes, into which catalysis is integrated, mediated by multifunctional materials (combine different functionalities into one smartly engineered material) and/or spatial organization of materials in dynamically operated packed-bed reactors.

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Project website

Solar hydrogen production from seawater using stabilized plasmonic photocatalysts. 01/11/2019 - 31/10/2021

Abstract

In 2012 international shipping emitted about 800 Mton CO2, 18.6 Mton NOx and 10.6 Mton SOx. It is expected that by 2050 these emissions will increase by 250% if no actions are taken. Therefore, scientific research for greener fuel alternatives is highly needed, and hydrogen has been identified as a promising candidate in that context. In this project, abundant seawater (rather than scarce pure water) will be split into hydrogen and oxygen gas using TiO2-based photocatalysts. The major drawback of TiO2 is the fact that it is only activated by ultraviolet (UV) light, corresponding to less than 5% of the incident solar spectrum on Earth. As a solution, the photocatalysts will be modified with ordered bimetallic gold-silver nanoparticles that strongly interact with sunlight. To ensure stability on the long term, even in the presence of a saline reaction environment, the plasmonic nanoparticles will be capped by a protective shell using wet-chemical synthesis techniques. The shell also acts as a spacer layer between the plasmonic cores that tunes the resulting interparticle distance and hot-spot formation. All structures will be thoroughly characterized down to the nanoscale, and action spectrum analysis will be performed in collaboration with Hokkaido University. Seawater splitting is only a very recently studied application. The use of plasmonic nanostructures in that regard is unprecedented, meaning the results from this project will move well beyond the state-of-the-art.

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Solar active self-cleaning and air purifying coatings using plasmon embedded titania. 01/11/2019 - 30/10/2021

Abstract

Soot is considered to be the second-largest contributor to global excess radiative forcing after CO2 and deemed responsible for 7 million premature deaths annually according to WHO. We propose an efficient photocatalyst for soot degradation (with simultaneous NOx reduction), using solar light as energy input. Photocatalytic oxidation is often achieved with TiO2 as photo-active material. The main drawback of TiO2 is its large band gap, which limits the overall solar light response to the UV region of the spectrum. Plasmonic photocatalysis using noble metal nanoparticles (NPs) has emerged as a promising technology to expand the activity window of traditional photocatalysts to the entire UV-visible light region of the solar spectrum. In this project, gold and silver NPs will be merged to overcome their individual limitations and form stable bimetallic NPs with highly tuneable plasmonic properties over a wide wavelength range. These plasmonic NPs will be embedded in TiO2 coatings. The plasmonic enhancement of photocatalytic air purifying and selfcleaning coatings will be studied in the laboratory by FTIR spectroscopy, contact angle measurements, digital imaging analysis and action spectrum analysis, as well as through real-life validation experiments in different cities, that illustrate the relevance of this research to the broader audience and potential investors. The proposed technology will be developed from TRL 2/3 to 5 including a CEA and possible recycling options.

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Semi-active photocatalysis technology for abatement of urban air pollution. 01/10/2019 - 30/06/2021

Abstract

The goal of this project is to develop semi-active photocatalytic systems for mitigating air pollution in urban environments. With semi-active systems is meant photocatalytic systems with (i) improved functionality (enhanced activity under solar light conditions), (ii) in which the transfer of pollutants to the photocatalytic surfaces is increased (by inducing natural or forced convection) and (iii) where the sunlight is optimally utilized by optimizing the received light intensity. The hypothesis is that systems that meet these conditions are superior to so-called passive photocatalytic systems. In this project, a promising plasmon-enhanced photocatalytic material, developed by our research group, will be characterized in terms of its sensitivity to sunlight. The relevant reaction kinetic parameters will hereby be determined and will be used for designing semi-active air purification systems based on computational fluid dynamics (CFD) models, thus limiting the need for extensive experiments. The most promising system will then be built on scale model and will be extensively tested under controlled conditions. Finally, a demonstration model will be built in a realistic environment. The ultimate goal of the IOF-POC project is to demonstrate the feasibility of semi-active photocatalytic systems and thus to awaken the interest of potential industrial partners and other stakeholders.

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In-line quantization of the hydrogen gas yield from photoelectrochemical treatment of volatile organic compounds. 01/01/2019 - 31/12/2021

Abstract

The goal of this project is to simultaneously address two persistent needs of today's society: sustainable energy production and good air quality. TiO2-based photocatalysis has proven to be successful in both light-driven hydrogen production as well as the degradation of organic pollutants. In this project the intention is to couple both applications in a single device, this way recovering part of the energy stored in the organic molecules as hydrogen gas, while mineralizing the carbon fraction to CO2. This process can be performed in a photoelectrochemical cell. Oxidation of VOCs occurs at the photo-anode, while hydrogen is produced at the cathode on the opposite side of a proton-conducting solid electrolyte membrane. Accurate and in-line detection of hydrogen gas as the desired reaction product is crucial for a thorough understanding of the cell operation. This grant is thus intended for purchasing a gas chromatograph with a state-of-the-art Barrier Ionization Discharge (BID) trace detection system for accurate analysis of hydrogen gas production at the cathode, that will complement existing infrastructure used to analyze photocatalytic VOC degradation at the photo-anode.

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Ordered bimetallic plasmonic nanostructures for photocatalytic soot degradation. 01/10/2018 - 30/09/2022

Abstract

Soot is considered to be the second-largest contributor to global excess radiative forcing after CO2 and deemed responsible for tripling the amount of premature deaths by 2060. We therefore propose a fundamental study to develop an efficient photocatalyst for the degradation of soot deposits, using (solar) light as the energy input. Photocatalytic oxidation is often achieved with TiO2 as the photoactive material. The main drawback of TiO2 is its large band gap, which limits the overall solar light response to the UV region of the spectrum. As a solution, plasmonic photocatalysis using noble metal nanoparticles (NPs) has emerged as a promising technology to expand the activity window of traditional photocatalysts to the entire UV-visible light region of the solar spectrum. In this project gold and silver NPs will be merged to overcome their individual limitations and form stable bimetallic NPs with highly tunable plasmonic properties over a wide wavelength range. These bimetallic NPs will be organized as an ordered plasmonic nanostructure, that will be characterized from bulk to nanoscale, a part of which in collaboration with the Institute for Catalysis at Hokkaido University, Japan. The effect of plasmonic enhancement on the photocatalytic soot degradation mechanism will be studied on a fundamental level by in-situ FTIR spectroscopy, but also through larger scale demonstration experiments that illustrate the relevance of this research to the broader audience.

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Synergy of plasmonic structures, affinity elements and photosensitizers for electrosensing of pharmaceuticals 01/08/2018 - 31/07/2021

Abstract

The main objective of the PLASMON-ELECTROLIGHT project is to elaborate an efficient sensing strategy to measure pharmaceuticals. The detection technique will be developed from an original photoelectrochemical detection strategy that is boosted by advanced photosensitizers, plasmonic enhancement, and affinity recognition. The photoactive hybrid materials must be designed carefully through rational choice of photosensitizers and metallic nanostructures, theoretical modeling, and experimental correlations. Next, the materials will be combined with biorecognition elements and employed as photoelectrochemical sensor. Our objectives also include a better understanding of the mechanism for plasmonic enhancement of photosensitizers' activity, developing new photoreactive materials and better methods to tests them. This will contribute to different field of chemical sensing, material science, and energy conversion.

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Photoelectrochemical abatement of methane waste with simultaneous energy recovery. 01/10/2018 - 30/09/2020

Abstract

Methane has recently been under attention as the atmospheric methane concentration is increasing more rapidly than initially expected. As methane is the second largest contributor to the enhanced greenhouse effect, this increases the urge for sustainable methane mitigation strategies in contrast to the current handling of methane emissions (e.g. venting). In this project a sustainable methane mitigation strategy, namely photoelectrochemical (PEC) methane degradation, is presented, which has not been studied before. In a PEC cell both mineralization of methane (at the photo-anode) and hydrogen evolution (at the cathode) are combined in a single device that runs solely on (solar) light as the energy input. First, the PEC cell will be optimized by selecting the best performing photo-anode material using the knowledge attained at the Wuhan University of Technology (China), also studying less conventional materials, nanostructures and synthesis strategies. As methane-rich waste streams are often gas mixtures, the influence of different common chemical compounds will be investigated both on overall cell performance, as well as in-situ. Finally, the effect of different reaction conditions will also be studied, as these factors are known to strongly influence photodriven processes. In summary, this project will allow us to evaluate the promise of PEC-technology for energy-efficient abatement of methane waste, while providing valuable new insight into the reaction mechanisms.

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Project website

Screen printing facilities and high resolution Raman imaging of (printed) surfaces and materials. 01/05/2018 - 30/04/2021

Abstract

This Hercules proposal concerns screen printing facilities. Screen printing facilities enable UAntwerp to pioneer in the field of electronics, sensors and photocatalysis by (1) developing unique (photo)sensors/detectors (e.g. electrochemical sensors, photovoltaics, photocatalysis) by printing (semi)conducting materials on substrates, (2) designing parts of Internet of Things modules with more flexibility and more dynamically, meanwhile creating a unique valorization potential and IP position.

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Infrastructure for imaging nanoscale processes in gas/vapour or liquid environments. 01/05/2018 - 30/04/2021

Abstract

Processes in energy applications and catalysis as well as biological processes become increasingly important as society's focus shifts to sustainable resources and technology. A thorough understanding of these processes needs their detailed observation at a nano or atomic scale. Transmission electron microscopy (TEM) is the optimal tool for this, but in its conventional form it requires the study object to be placed in ultrahigh vacuum, which makes most processes impossible. Using environmental TEM holders, the objects can be placed in a gas/vapour or liquid environment within the microscope, enabling the real time imaging, spectroscopic and diffraction analysis of the ongoing processes. This infrastructure will enable different research groups within the University of Antwerp to perform a wide range of novel research experiments involving the knowledge on processes and interactions, including among others the growth and evolution of biological matter, interaction of solids with gasses/vapours or liquid for catalysis, processes occurring upon charging and discharging rechargeable batteries, the nucleation and growth of nanoparticles and the detailed elucidation of intracellular pathways in biological processes relevant for future drug delivery therapies and treatments.

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Plasmon-enhanced photocatalytic self-cleaning coatings. 02/04/2018 - 30/09/2019

Abstract

The goal of this IOF-POC project is to develop a market viable self-cleaning coating. The self-cleaning effect relies on the concept of photocatalysis; an advanced oxidation technology that enables the degradation of organic pollutants with light as an energy input and a semiconductor (here TiO2) as the catalyst. The main challenge of the project is to significantly increase the light-efficiency of the coating, while keeping the coating as transparent and cost-effective as possible. After optimizing the coating parameters and evaluating its cost-effectiveness, the ultimate target is to develop several prototypes that demonstrate the applicability in the building sector (e.g. skyscraper windows), as solar panel cover plates, or self-cleaning fish tanks.

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Research Council Award 2017 - Award Verbeure: Applied & Exact Sciences 01/12/2017 - 31/12/2018

Abstract

Research Council Award 2017 - Award Verbeure: Applied & Exact Sciences The award will be used for funding the further development and dissemination of the research on plasmonics for improving photocatalysis. Elucidation of the fundamental operating principle, as well as the actual application of the technology, are both key aspects.

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Energy from methane waste: catalyst selection, parameter study and in-situ investigation of a photo-electrochemical cell. 01/10/2017 - 30/09/2018

Abstract

Methane has recently been under attention as the atmospheric methane concentration is increasing more rapidly than initially expected. As methane is the second largest contributor to the enhanced greenhouse effect, this increases the urge for sustainable methane mitigation strategies in contrast to the current handling of methane emissions (e.g. venting). In this project a sustainable methane mitigation strategy, namely photo-electrochemical (PEC) methane degradation, is presented, which has not been studied before. In a PEC cell both mineralization of methane (at the photo-anode) and hydrogen evolution (at the cathode) are combined in a single device that runs solely on (solar) light as the energy input. First, the PEC cell will be optimized by selecting the best performing photo-anode material, also studying less conventional materials, nanostructures and synthesis strategies. As methane-rich waste streams are often gas mixtures, the influence of different common chemical compounds (O2, CO2, NOx, H2O, NH3) will be investigated both on overall cell performance, as well as in-situ. Finally, the effect of different reaction conditions (temperature, flow rate and light intensity) will also be studied, as these factors are known to strongly influence photo-driven processes. In summary, this project will allow us to evaluate the promise of PEC-technology for energy-efficient abatement of methane waste, while providing valuable new insight into the reaction mechanisms.

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Magnetized Plasmonic Catalysts for Photochemical Applications. 01/04/2017 - 31/03/2018

Abstract

Practical applications of liquid solar light-driven photocatalytic reactions are hampered by two main factors: (i) limited (visible) light absorption and (ii) problematic post-separation due to the nano-sized dimensions of the catalysts involved. In this BOF-KP a technological solution is developed to address both problems simultaneously. In a first stage stabilized magnetic nanoclusters will be prepared that can be separated fast and effectively. Secondly, UV-visible light responsive plasmonic nanoparticles/photocatalysts are anchored to these stabilized magnetic nanoclusters. This will reduce operation costs since freely available solar light can be utilized more effectively. Additionally, costs are avoided associated with down-stream catalyst separation. Magnetized plasmonic photocatalysts will be tested toward waste water purification (phenol degradation), whereas pure magnetized plasmonic nanoparticles will be tested as catalysts toward the direct selective photo-conversion of aniline to di-azobenzene. Using plasmonic metal nanoparticles for direct photochemical selective transformations provides an alternative 'green' synthesis process. Traditionally such reactions require elevated temperature or pressure, as well as the addition of stoichiometric quantities of specific chemicals that lead to unwanted waste streams. The method proposed in this BOF-KP only involves free sunlight as the energy source, a nano-catalyst that can be easily recovered, no additional chemicals are required and the entire reaction is carried out at room temperature.

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Photocatalytic gas scrubber as innovative air purification technology. 01/01/2016 - 31/12/2016

Abstract

Air pollution is one of the problems that has attracted specific attention since the start of the 21st century. Volatile organic compounds (VOCs), originating from furniture or building materials amongst others, are an important class of pollutants and the concentration indoors are often several times higher than outdoors. The main goal is the complete mineralization of VOCs based on a photocatalytic oxidation process which can be carried out under mild reaction conditions (low pressure and temperature). The methodology that will be used is to transfer the VOCs from the gas phase to the aqueous phase by means of a scrubber to ensure an efficient photocatalytic degradation under UV light. The light efficiency will be optimized based on two different methods. The first method is via modification of standard TiO2 with plasmonic silver nanostructures. These nanostructures display surface plasmon resonance (SPR) in the UV part of the spectrum, which entails a significant electric near-field enhancement. The build-up of these intense local electric fields allows an efficient concentration of the incident photon energy in small volumes near the nanostructures. Since the rate of electron-hole pair formation is proportional to the intensity of the electric field, a drastic increase in charge carrier formation occurs. In order for this plasmonic "lens effect" to work, an energy match between the bandgap energy of the semiconductor and the energy associated with the SPR is required, which is the case for silver nanostructures. A second method to increase the UV light efficiency is by means of an innovative reactor design. A scrubber will be used to transfer the contaminated air flow to the aqueous phase leading to an enrichment of the VOCs in the aqueous phase. After that, the VOCs will be photocatalytically degraded in the aqueous phase, which is a better known concept than degradation in gas phase. The VOC degradation will occur via an optimized reactor design in which a UV transparent capillary tube is coated on the inside with photoactive material. This tube will be winded around a UV light source. In this way, there is a large contact time between pollutant and catalyst. Furthermore, this design ensures an active washing of the catalyst surface avoiding possible deactivation of the catalyst.

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Fabrication and characterization of plasmonic TiO2 anodes for energy recovery from contaminated air. 01/02/2015 - 31/12/2015

Abstract

In this BOF KP TiO2-based photo-anodes are modified with plasmonic noble metal nanoparticles that shift the window of operation towards the visible light region of the solar spectrum. The main objectives are the detailed photo-electrochemical characterization of these plasmonic TiO2 photo-anodes and the fundamental elucidation of the plasmon-mediated working mechanism.

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Sunlight-driven photo-electrochemical hydrogen production from air contaminated with volatile organic compounds. 01/10/2014 - 30/09/2017

Abstract

Today's society has to cope with two persistent demands: sustainable energy production and a clean, healthy environment. This project aims at addressing both issues simultaneously in a single device. Air contaminated with volatile organic compounds (VOC) is administered to the photoanode compartment of a photo-electrochemical (PEC) cell. The photo-anode consists of a photocatalyst (TiO2) that mineralizes those VOCs under illumination. Protons formed during photoreaction diffuse through a solid electrolyte membrane towards the cathode side of the PEC cell. At the cathode protons are reduced with photogenerated electrons that are externally conducted from anode to cathode and hydrogen fuel is recovered. A big challenge of the proposed concept is to make the photo-anode visible light active. Photocatalysts such as TiO2 are activated only by UV light, which represents but 5% of the solar spectrum. In this project the photo-anode will be modified with unconventional and ffordable 'plasmonic' metal nanostructures with photoresponse tuned to the solar spectrum. They are expected to boost the PEC cell's efficiency by expanding the activity window of the photo-anode towards visible light or by improving the performance in the available wavelength range. Physico-chemical characterization, theoretical simulations of the light-matter interaction and actual PEC cell performance tests will lead to fundamental understanding and efficiency improvement of this sunlight-driven process.

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Noble metal nanoparticle antenna based plasmonics to improve photocatalysis. 01/10/2012 - 30/09/2014

Abstract

Millions of people are currently suffering from the consequences of poor indoor air quality. Photocatalysis is a promising approach to remove harmful components from the air. The bottleneck thus far is the low efficiency of the photocatalytic reactions. A big step forward can be achieved by light harvesting antenna systems based on metal nanoparticles. They capture light of lower energy (in the visible light region) and with a higher efficiency. Photocatalytic ceramic foams with nanoparticle antennas are synthesized, characterized and tested towards their air purification properties.

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Noble metal nanoparticle antenna based plasmonics to improve photocatalysis. 01/10/2010 - 30/09/2012

Abstract

Millions of people are currently suffering from the consequences of poor indoor air quality. Photocatalysis is a promising approach to remove harmful components from the air. The bottleneck thus far is the low efficiency of the photocatalytic reactions. A big step forward can be achieved by light harvesting antenna systems based on metal nanoparticles. They capture light of lower energy (in the visible light region) and with a higher efficiency. Photocatalytic ceramic foams with nanoparticle antennas are synthesized, characterized and tested towards their air purification properties.

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