Edge‐Enriched Ultrathin MoS₂ Embedded Yolk‐Shell TiO₂ with Boosted Charge Transfer for Superior Photocatalytic H₂ Evolution

Abstract

Abstract Exploring TiO 2 ‐photocatalysts for sunlight conversion has high demand in artificial photosynthesis. In this work, edge‐enriched ultrathin molybdenum disulfide (MoS 2 ) flakes are uniformly embedded into the bulk of yolk‐shell TiO 2 as a cocatalyst to accelerate photogenerated‐electron transfer from the bulk to the surface of TiO 2 . The as‐formed MoS 2 /TiO 2 (0.14 wt%) hybrids exhibit a high hydrogen evolution rate (HER) of 2443 µmol g −1 h −1 , about 1000% and 470% of that of pristine TiO 2 (247 µmol g −1 h −1 ) and bulk MoS 2 decorated TiO 2 (513 µmol g −1 h −1 ). Such a greatly enhanced HER is attributed to the exposed catalytic edges of the ultrathin MoS 2 flakes with a robust chemical linkage (TiS bond), providing rapid charge transfer channels between TiO 2 and MoS 2 . The catalytic stability is promoted by the antiaggregation of the highly dispersed MoS 2 flakes in the bulk of yolk‐shell TiO 2 . The exponential fitted decay kinetics of time‐resolved photoluminescence (ns‐PL) spectra illustrates that embedding ultrathin MoS 2 flakes in TiO 2 effectively decreases the average lifetime of PL in the MoS 2 /TiO 2 hybrids (τ ave = 4.55 ns), faster than that of pristine TiO 2 (≈7.17 ns) and the bulk MoS 2 /TiO 2 (≈6.13 ns), allowing a superior charge separation and charge trapping process for reducing water.