Publication date: 21st July 2025
The (photo)electrochemical conversion of CO₂ into value-added chemicals and fuels is a promising strategy to provide additional energy sources to address humanity’s increasing energy needs. Among the various approaches, photoelectrochemical (PEC) CO₂ reduction is particularly attractive due to its potential for direct solar-to-chemical energy conversion. However, realizing such devices requires selective and stable multi-carbon (C₂⁺) product formation, which remains a key challenge in the field. In our recent work, we have focused on improving both the selectivity and stability of PEC systems by using novel photocathode materials and tailored interfaces.
Here, we show the power of operando spectroscopic ellipsometry (SE) to continuously track the degradation of TiO₂ protective coatings during PEC operation across a range of pH and illumination conditions.1 In addition, we propose a novel time-resolved Kelvin probe force microscopy (KPFM) approach to enable spatially resolved mapping of surface photovoltage, which reveals the link between local microstructure and charge transport behavior.2
On the material side, we will demonstrate that ZnTe-based photocathodes, modified through a controlled electrodeposition-annealing route to generate Zn-rich surfaces, show unusual light-driven carbon product selectivity.3 Additionally, we introduce copper-tantalate (Cu₂Ta₄O₁₁, CTO) thin films, synthesized via a sodium flux-mediated technique, as a novel photocathode material. The resulting Na-doped CTO thin films, particularly after selective surface etching to remove CuO, exhibit improved ethylene selectivity and reduced photocorrosion.4
[1] M. Schieda, F. M. Toma et al, in preparation
[2] M. Pourmahdavi, M. Schieda, R. Raudsepp, S. Fengler, J. Kollmann, Y. Pieper, T. Dittrich, T. Klassen, and Francesca M. Toma, Correlating Local Morphology and Charge Dynamics via Kelvin Probe Force Microscopy to Explain Photoelectrode Performance, PRX Energy 2025, 4, 023010
[3] G. Zeng, G. Liu, G. Panzeri, C. Kim, C. Song, O. J. Alley, A. T. Bell, A. Z. Weber, and Francesca M. Toma, Surface Composition Impacts Selectivity of ZnTe Photocathodes in Photoelectrochemical CO2 Reduction Reaction, ACS Energy Lett. 2025, 10 (1), 34-39.
[4] A. Köche, K. Hong, S. Seo, F. Babbe, H. Gim, K.-H. Kim, H. Choi, Y. Jung, I. Oh, G. V. Krishnamurthy, M. Störmer, S. Lee, T.-H. Kim, A. T. Bell, S. Khan, C. M. Sutter-Fella, F. M. Toma, Copper Tantalate by a Sodium-Driven Flux-Mediated Synthesis for Photoelectrochemical CO2 Reduction. Small Methods 2025, 2401432.
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.