Reductive Reconstruction Activates High‐Entropy Perovskite Fiber–ZnIn 2 S 4 Interfaces in Photocatalytic Hydrogen Evolution and Solar Water Evaporation

This is the authors' abstract. We don't add key points for this paper.

Solar‐driven hydrogen production offers a sustainable route for converting solar energy into chemical fuels, yet whether the nanoscale interfacial advantages achieved in particulate photocatalysts can be retained after macroscale membrane assembly remains a fundamental challenge. Herein, a hydrogen‐induced lattice reconstruction strategy is developed to regulate high‐entropy perovskite La 0.95 (Fe 0.2 Co 0.2 Ni 0.2 Cr 0.2 Ti 0.2 ) 1.05 O 3‐δ (LB5O 3 ) nanofibers for integration with ZnIn 2 S 4 (ZIS). Controlled H 2 reduction modifies near‐surface perovskite environments of the LB5O 3 fibers, followed by in situ growth of ZIS nanosheets to form reconstruction‐derived oxide–semiconductor interfaces, yielding reconstructed heterojunctions with a particulate H 2 evolution rate of 16 673 µmol·h −1 ·g −1 . To bridge the gap between particulate catalytic efficiency and functional device translation, these hybrid fibers were assembled into a supported floating membrane. When operated in the floating configuration, the membrane exhibits localized photothermal heating and continuous capillary water transport at the air–water interface, and achieves an H 2 evolution rate of 17 875 µmol·h −1 ·g −1 . The fibrous architecture further achieves a dark‐corrected solar evaporation rate of 1.60 kg·m −2 ·h −1 with a solar‐to‐vapor conversion efficiency of 87.3%. Furthermore, outdoor field tests conducted under naturally fluctuating sunlight demonstrate consistent hydrogen production across five days of cycling tests alongside simultaneous freshwater production from simulated seawater.