Periodic Reporting for period 1 - SUN2CHEM (Novel photo-assisted systems for direct Solar-driven redUctioN of CO2 to energy rich CHEMicals)
Período documentado: 2020-10-01 hasta 2022-03-31
SUN2CHEM aims to solve imminent CO2 emission that is directly related to the climate change issue, as well as policy of EU to reach net-zero goal. Technical issues/challenges to find an efficient and environmentally friendly way to achieve ethylene have been addressed by developing highly efficient photoelectrochemical and photocatalytic cell with mechanistic understanding on the reaction system. It is expected that the objectives of SUN2CHEM, after being fulfilled, have huge impact for lowering CO2 emission in Europe (potentially 862 Mt) by photoelectrochemical and photocatalytic cell with high solar to ethylene conversion efficiency. This has five major importance for (European) society for 1) large contribution to mitigate climate change, 2) opportunities for economic development for solar driven ethylene production, 3) consortium of project directly related to establishment of European-international innovation for renewable technology, 4) building a sustainable energy system and 5) deepening international collaboration for realization of clean energy research and development. SUN2CHEM’s main objective is to develop solutions to achieve efficient solar-driven CO2 reduction to energy rich chemicals. For that purpose, SUN2CHEM partners are conjointly developing all the components to be integrated into tandem photoelectrochemical cells and advanced photocatalytic reactors targeting ethylene as the final product.
WP1-Specifications on simple and complex photocatalytic composites, metal oxide photoelectrodes and solar-driven catalytic systems for ethylene production have been made by deciding parameters for evaluation of project goal.
WP2-Different synthesis approaches have been investigated: colloidal protective methods, photodeposition, Impregnation/chemical reduction, aiming at controlling the shape, the morphology, the content and the composition. The influence of total M content, of M1/M2 ratio, of M nanoparticle size distribution and dispersion onto SCs are investigated as well. In task 2.4 gas-phase photocatalytic CO2 reduction has been performed under continuous CO2 flow in the set-up, allowing to follow kinetics of CO2 reduction and products formation.
WP3-BiVO4 photoanodes and Cu2O photocathodes have been synthesised and thoroughly characterised for the tandem device. Nanoparticulated and nanostructured BiVO4 photoelectrodes have been grown and studied for both, oxygen evolution reaction (OER) and hole scavenger oxidation. BiVO4 nanoparticles have been prepared by both batch and continuous-flow processes at low temperatures, in an aqueous medium, using inexpensive precursors. Additionally, the continuous flow synthesis is suitable to scale-up the synthesis and the photoelectrodes. Nanostructured BiVO4 photoanodes have been produced and optimised by two different electrodeposition (ED) methods targeting photocurrent of 7 mA·cm-2. In line with the electrodeposited photoelectrodes, different photoanodes were prepared where nanorods of TiO2 and WO3 were previously grown, in order to obtain different heterostructures with BiVO4. On the other hand, efficient Cu2O photocathodes + CO2 RR catalyst have been prepared through the optimisation of a Cu2O buried junction. To sum up, stable photoelectrodes for the tandem PEC device have been synthesised through different optimise processes and the progress in the performance of the photocathode and the photoanode are in the range of the targeted ones ( ̴4.5 mA·cm-2 at 1.23 V vs RHE for BiVO4 and ̴6 mA·cm-2 at 0 V vs RHE for Cu2O) and mechanistic studies are being performed to understand the limiting factors of such photoelectrodes.
WP4-For CO2 RR catalyst, we have used Cu metal modified with Chloride salt electrolyte, achieving electrochemical ethylene production Faradaic efficiency of > 70%. Using this catalyst, we realised photocathode – CO2 RR catalyst device. Initially, Cu2O based device were chosen as light absorber, later we changed it to Lead halide perovskite-based device, which achieved both sufficient current density and voltage (20 mA/cm2 and 1.0 V). Later, PSC-Cu photocathode achieved ethylene production Faradaic efficiency around 15% with partial photocurrent density around 1.5 mA/cm2 at -0.4 VRHE.
WP7-A report has been provided on the data needed to perform LCA and LCC analysis, describing the common methodology that will be applied to this analysis and identifies the information that will be collected from a literature study and that has to be delivered by partners.
WP9-A communication and dissemination plan has been published, framing the different activities to be performed. The website of the project is available from the first months of the project and some scientific papers have already been published. Some partners have already participated in events to give visibility to the project.
WP2-Different synthesis approaches have been investigated: colloidal protective methods, photodeposition, Impregnation/chemical reduction, aiming at controlling the shape, the morphology, the content and the composition. The influence of total M content, of M1/M2 ratio, of M nanoparticle size distribution and dispersion onto SCs are investigated as well. In task 2.4 gas-phase photocatalytic CO2 reduction has been performed under continuous CO2 flow in the set-up, allowing to follow kinetics of CO2 reduction and products formation.
WP3-BiVO4 photoanodes and Cu2O photocathodes have been synthesised and thoroughly characterised for the tandem device. Nanoparticulated and nanostructured BiVO4 photoelectrodes have been grown and studied for both, oxygen evolution reaction (OER) and hole scavenger oxidation. BiVO4 nanoparticles have been prepared by both batch and continuous-flow processes at low temperatures, in an aqueous medium, using inexpensive precursors. Additionally, the continuous flow synthesis is suitable to scale-up the synthesis and the photoelectrodes. Nanostructured BiVO4 photoanodes have been produced and optimised by two different electrodeposition (ED) methods targeting photocurrent of 7 mA·cm-2. In line with the electrodeposited photoelectrodes, different photoanodes were prepared where nanorods of TiO2 and WO3 were previously grown, in order to obtain different heterostructures with BiVO4. On the other hand, efficient Cu2O photocathodes + CO2 RR catalyst have been prepared through the optimisation of a Cu2O buried junction. To sum up, stable photoelectrodes for the tandem PEC device have been synthesised through different optimise processes and the progress in the performance of the photocathode and the photoanode are in the range of the targeted ones ( ̴4.5 mA·cm-2 at 1.23 V vs RHE for BiVO4 and ̴6 mA·cm-2 at 0 V vs RHE for Cu2O) and mechanistic studies are being performed to understand the limiting factors of such photoelectrodes.
WP4-For CO2 RR catalyst, we have used Cu metal modified with Chloride salt electrolyte, achieving electrochemical ethylene production Faradaic efficiency of > 70%. Using this catalyst, we realised photocathode – CO2 RR catalyst device. Initially, Cu2O based device were chosen as light absorber, later we changed it to Lead halide perovskite-based device, which achieved both sufficient current density and voltage (20 mA/cm2 and 1.0 V). Later, PSC-Cu photocathode achieved ethylene production Faradaic efficiency around 15% with partial photocurrent density around 1.5 mA/cm2 at -0.4 VRHE.
WP7-A report has been provided on the data needed to perform LCA and LCC analysis, describing the common methodology that will be applied to this analysis and identifies the information that will be collected from a literature study and that has to be delivered by partners.
WP9-A communication and dissemination plan has been published, framing the different activities to be performed. The website of the project is available from the first months of the project and some scientific papers have already been published. Some partners have already participated in events to give visibility to the project.
WP1-Should indicate how relevant SUN2CHEM is to the current urgent problem of CO2 emissions by reflecting realistic parameters to the project (% = mW/cm2 scale of CO2 conversion efficiency RR).
WP2-Some of the prepared and optimised bi-metallic Au-Ag and Cu-based/SC1-SC2-MOF heterojunctions allow to yield increased CH4 productivity with total selectivity from CO2 photocatalytic reduction under visible light irradiation. A new photocatalytic device has been designed in order to carried out photocatalytic gas phase CO2 reduction under pressure (5-10 bars) thus expecting to drive the reaction of those materials towards ethylene production.
WP3-Includes a task to understand the limiting factors of photoelectrodes to further increase their performance. In the last year, an 250 % improvement in the BiVO4 photoanode has been reached, which shows photocurrents of 4.4 mA·cm-2 at 1.23 V vs RHE, that is not far away from the targeted values. Additionally, the scalability into an efficient photoanode of 50 cm2 could be closer due to the large-scale production of BiVO4 under continuous-flow conditions. Regarding the Cu2O photocathodes, a photocurrent of ̴6 mA·cm-2 at 0.0 V vs RHE as short circuit Jph for photocathode with modest Vph of 1.0 V is achieved, which is comparable to the state of the art of Cu2O photocathodes made with similar configuration. Thus, the scalability of the optimised synthetic method will be check as a potential protocol suitable for the scaling-up.
WP4-As the state of the art does not go beyond a partial photocurrent density of 5 mA/cm2 for ethylene production, SUN2CHEM will be the first to obtain a result on such a device. Beyond the experimental point of view, the WP result should inspire the potential commercialisation of solar ethylene production since the system should have a lower discounted solar fuel cost than the typical PV-EC approach.
WP7-It is expected that IFPEN will conduct a combined LCA and LCCA analysis. The results of these assessments will provide information on the environmental and economic performance of the new ethylene synthesis routes developed within SUN2CHEM, in comparison with the historic fossil-resource based synthesis route.
WP8-Right foundations will be put in place during the course of the project to become successful commercial applications in the future beyond the scope of the project and when higher TRL levels are reached. It also implies extensive market intelligence activities in order to identify relevant market trends and competitive threats aligning project outputs with the external business environment, requirements and standards.
WP2-Some of the prepared and optimised bi-metallic Au-Ag and Cu-based/SC1-SC2-MOF heterojunctions allow to yield increased CH4 productivity with total selectivity from CO2 photocatalytic reduction under visible light irradiation. A new photocatalytic device has been designed in order to carried out photocatalytic gas phase CO2 reduction under pressure (5-10 bars) thus expecting to drive the reaction of those materials towards ethylene production.
WP3-Includes a task to understand the limiting factors of photoelectrodes to further increase their performance. In the last year, an 250 % improvement in the BiVO4 photoanode has been reached, which shows photocurrents of 4.4 mA·cm-2 at 1.23 V vs RHE, that is not far away from the targeted values. Additionally, the scalability into an efficient photoanode of 50 cm2 could be closer due to the large-scale production of BiVO4 under continuous-flow conditions. Regarding the Cu2O photocathodes, a photocurrent of ̴6 mA·cm-2 at 0.0 V vs RHE as short circuit Jph for photocathode with modest Vph of 1.0 V is achieved, which is comparable to the state of the art of Cu2O photocathodes made with similar configuration. Thus, the scalability of the optimised synthetic method will be check as a potential protocol suitable for the scaling-up.
WP4-As the state of the art does not go beyond a partial photocurrent density of 5 mA/cm2 for ethylene production, SUN2CHEM will be the first to obtain a result on such a device. Beyond the experimental point of view, the WP result should inspire the potential commercialisation of solar ethylene production since the system should have a lower discounted solar fuel cost than the typical PV-EC approach.
WP7-It is expected that IFPEN will conduct a combined LCA and LCCA analysis. The results of these assessments will provide information on the environmental and economic performance of the new ethylene synthesis routes developed within SUN2CHEM, in comparison with the historic fossil-resource based synthesis route.
WP8-Right foundations will be put in place during the course of the project to become successful commercial applications in the future beyond the scope of the project and when higher TRL levels are reached. It also implies extensive market intelligence activities in order to identify relevant market trends and competitive threats aligning project outputs with the external business environment, requirements and standards.