Photoelectrochemical water splitting is an attractive solar-to-hydrogen pathway. However, the lifetime of photoelectrochemical devices is hampered by severe photocorrosion of semiconductors and instability of co-catalysts. Here we report a strategy for stabilizing photoelectrochemical devices that use a polyacrylamide hydrogel as a highly permeable and transparent device-on-top protector. A hydrogel-protected Sb2Se3 photocathode exhibits stability over 100 h, maintaining ~70% of the initial photocurrent, and the degradation rate gradually decreases to the saturation level. The structural stability of a Pt/TiO2/Sb2Se3 photocathode remains unchanged beyond this duration, and effective bubble escape is ensured through the micro gas tunnel formed in the hydrogel to achieve a mechanically stable protector. We demonstrate the versatility of the device-on-top hydrogel protector under a wide electrolyte pH range and by using a SnS photocathode and a BiVO4 photoanode with ~500 h of lifetime.
Bibliographical noteFunding Information:
This work was supported by the National Research Foundation (NRF) of Korea grant (numbers 2021R1A3B1068920 (J.M.), 2021M3H4A1A03049662 (J.M.), 2021R1A2C2009070 (Hyungsuk Lee) and 2021R1I1A1A01060058 (J.T.)), funded by the Ministry of Science and ICT. This research was also supported by the Yonsei Signature Research Cluster Program of 2021 (2021–22-0002, J.M.). We thank M. Na for TEM analysis.
© 2022, The Author(s), under exclusive licence to Springer Nature Limited.
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Renewable Energy, Sustainability and the Environment
- Fuel Technology
- Energy Engineering and Power Technology