Metal-organic framework-derived nitrogen-doped carbon-coated hollow tubular In2O3/CdZnS heterojunction for efficient photocatalytic hydrogen evolution

Using photocatalytic hydrogen evolution (PHE) technology is a powerful way to solve the energy shortage. In this study, a hexagonal hollow tubular nitrogen-doped carbon (N−C)-coated In2O3/CdZnS heterojunction photocatalyst was in situ synthesized using a simple oil bath heating method. Results show that the PHE rate of N−C/In2O3/CdZnS (∼22.87 µmol h−1) is ∼2.4 times that of pristine CdZnS (∼9.49 µmol h−1) and ∼54.5 times that of pristine In2O3 (∼0.42 µmol h−1). After four cycles, the PHE rate can still retain more than 90% of the original. Its excellent photocatalytic performance is mainly attributed to the following aspects: (1) the N−C layer acts as an electron transport bridge, which ensures the efficient electron transfer of the photocatalytic reaction; (2) the hollow tubular structure enhances the light reflection and absorption; (3) the N−C/In2O3/CdZnS heterostructure improves the carrier recombination and photocorrosion; (4) the large specific surface area and mesoporous structure provide a large number of reactive sites. This study provides a novel idea for designing visible-light-type heterojunction catalysts.