All-Solid Z-Scheme Bi–BiOCl/AgCl Heterojunction Microspheres for Improved Electron–Hole Separation and Enhanced Visible Light-Driven Photocatalytic Performance

All-solid Z-scheme Bi-BiOCl/AgCl heterojunction microspheres are successfully prepared via hydrothermal, NaBH4 reduction and chemical deposition strategy. They are tested by various characterization methods, and they show that metal Bi is present after reduction and AgCl nanoparticles are successfully compounded onto BiOCl. Bi plays the role of a bridge connecting the two semiconductors of BiOCl and AgCl. All-solid Z-scheme heterojunction structures are formed successfully. The narrow band gap of the Z-scheme Bi-BiOCl/AgCl heterojunction microspheres is about 2.17 eV, which can expand the optical response range. Moreover, the photocatalytic hydrogen production rate still reaches 198.2 μmol h-1 g-1, extends the electron transport life, inhibits the recombination of electron hole pairs, and improves the photocatalytic activity.