Facile immobilization of Cd_0.7Zn_0.3S photocatalysts on flexible substrates for scalable hydrogen production

Photocatalysis offers significant potential for directly converting intermittent solar energy into storable hydrogen fuel. To transition photocatalytic hydrogen production from laboratory-scale research to large-scale applications, scalable photocatalyst sheets must be developed using straightforward immobilization methods on suitable substrates. In this work, Cd_0.7Zn_0.3S (CZS) particles were immobilized on four substrates via a simplified drop-casting process. The substrates and the resulting immobilized CZS photocatalysts were characterized. Among these, CZS immobilized on nonwoven cleanroom wipes (NCWs) exhibited the highest activity in 5 cm × 5 cm photocatalyst sheets. This enhanced performance can be attributed to the excellent wettability and multilayer fiber structure of NCWs, which promotes uniform photocatalyst immobilization, improved mass transfer, and efficient light absorption. Furthermore, the optimal photocatalyst sheet, scaled to 50 cm × 100 cm, was employed to generate hydrogen over a total area of 10 m² under natural sunlight. This demonstration highlights the potential of this scalable photocatalyst sheet for large-scale hydrogen production.