Proceedings of nanoGe September Meeting 2017 (NFM17)
Publication date: 20th June 2016
The coupling of light absorbers to cocatalysts is of fundamental importance for efficient solar-driven photoelectrocatalytic water splitting.1,2 Recently we achieved effective loading of visible light-active porous hybrid TiO2-PH (PH – polyheptazine, “graphitic carbon nitride”) photoanodes for water photooxidation with ultrasmall (~1-2 nm), highly disordered CoO(OH)x nanoparticles using a two-step impregnation method.3 Under visible light (λ > 420 nm) irradiation, the resulting photoanodes significantly outperformed photoanodes loaded with conventional cobalt-based cocatalyst (Co-Pi) comprising larger nanoparticles (~5 nm) both in terms of Faradaic efficiency of oxygen evolution (by the factor of 2) and performance stability under long-term irradiation.
The contribution will focus on elucidating the advantages of using ultrasmall CoO(OH)x nanoparticles as cocatalysts. Specifically, due to their high transparency in visible range, higher loading of porous photoanodes with cobalt catalytic sites could be achieved, while the photocurrent losses due to parasitic light absorption by the cocatalyst are minimized. Importantly, EXAFS data recorded before and after photoelectrocatalysis indicated that the significant enhancement in stability of ultrasmall CoO(OH)x nanoparticles in borate as compared to phosphate electrolytes can be explained by the difference in structural ordering dictated by interaction of the electrolyte anions with cobalt ions.
The impact of structural and optical properties of cocatalysts as well as the strong influence of the electrolyte composition on the activity and stability of photoelectrocatalytic systems comprising transition metal oxide electrocatalysts will be discussed in detail.
References
[1] M. Bledowski, L. Wang, S. Neubert, D. Mitoraj, R. Beranek, J. Phys. Chem., 2014, 118, 18951-18961.
[2] O. Khavryuchenko, L. Wang, D. Mitoraj, G. H. Peslherbe, R. Beranek, J. Coord. Chem., 2015, 68, 3317-3327.
[3] L. Wang, D. Mitoraj, O. V. Khavryuchenko, S. Turner, T. Jacob, R. Hockling, R. Beranek, ACS Catal. 2017, submitted.
nanoGe is a prestigious brand of successful science conferences that are developed along the year in different areas of the world since 2009. Our worldwide conferences cover cutting-edge materials topics like perovskite solar cells, photovoltaics, optoelectronics, solar fuel conversion, surface science, catalysis and two-dimensional materials, among many others.
Previously nanoGe Spring Meeting (NSM) and nanoGe Fall Meeting (NFM), MATSUS is a multiple symposia conference focused on a broad set of topics of advanced materials preparation, their fundamental properties, and their applications, in fields such as renewable energy, photovoltaics, lighting, semiconductor quantum dots, 2-D materials synthesis, charge carriers dynamics, microscopy and spectroscopy semiconductors fundamentals, etc.
International Conference on Hybrid and Organic Photovoltaics
International Conference on Hybrid and Organic Photovoltaics (HOPV) is celebrated yearly in May. The main topics are the development, function and modeling of materials and devices for hybrid and organic solar cells. The field is now dominated by perovskite solar cells but also other hybrid technologies, as organic solar cells, quantum dot solar cells, and dye-sensitized solar cells and their integration into devices for photoelectrochemical solar fuel production.
Asia-Pacific International Conference on Perovskite, Organic Photovoltaics and Optoelectronics
The main topics of the Asia-Pacific International Conference on Perovskite, Organic Photovoltaics and Optoelectronics (IPEROP) are discussed every year in Asia-Pacific for gathering the recent advances in the fields of material preparation, modeling and fabrication of perovskite and hybrid and organic materials. Photovoltaic devices are analyzed from fundamental physics and materials properties to a broad set of applications. The conference also covers the developments of perovskite optoelectronics, including light-emitting diodes, lasers, optical devices, nanophotonics, nonlinear optical properties, colloidal nanostructures, photophysics and light-matter coupling.
The International Conference on Perovskite Thin Film Photovoltaics Perovskite Photonics and Optoelectronics (NIPHO) is the best place to hear the latest developments in perovskite solar cells as well as on recent advances in the fields of perovskite light-emitting diodes, lasers, optical devices, nanophotonics, nonlinear optical properties, colloidal nanostructures, photophysics and light-matter coupling.