Synergistic effect of sulfur vacancy, internal electric field and Mo-S bond toward highly-efficient charge utilization for MoS2/Sv-MnS/ZnIn2S4 photocatalysts

ZnIn 2 S 4 is a promising and typical semiconductor for photocatalytic water splitting into hydrogen production. However, the low charge-carrier utilization restricts its hydrogen evolution performance and practical application. In this work, a synergistic strategy of sulfur vacancy (S v ), internal electric field (IEF) and Mo-S bond was utilized for improving the charge-carrier utilization of MoS 2 /S v -MnS/ZnIn 2 S 4 composites. In particular, Z-scheme S v -MnS/ZnIn 2 S 4 heterojunction not only tackled the charge-carrier recombination problem but also improved the redox capability. Meanwhile, Schottky-type MoS 2 /S v -MnS contact further promoted the charge transfer through Mo-S bond “bridge”, accelerated the surface hydrogen reduction reaction kinetics, and thus boosted the charge-carrier utilization. As a result, the optimal MoS 2 /S v -MnS/ZnIn 2 S 4 catalysts could expeditiously produce 1.75   mL of hydrogen production within 3   h, and achieve a photocatalytic hydrogen evolution rate of 13.02   mmol   g -1 h -1 . This work provides an ingenious method to synthesize ZnIn 2 S 4 -based photocatalysts with highly-efficient charge-carrier utilization.