Z-Scheme 2D/3D hierarchical MoS2@CoMoS4 flower-shaped arrays with enhanced full spectrum light photoelectrocatalytic activity for H2O2/p-aminophenol production and contaminant degradation

Abstract

Developing high-performance catalysts for converting naturally existing simple molecules/poisonous chemicals into value-added commodity chemicals with environmental and socioeconomic benefits is a great challenge. Herein, Z-scheme 2D/3D hierarchical MoS₂@CoMoS₄ flower-shaped arrays as dual-functional electrodes for photoelectrocatalytic (PEC) hydrogen peroxide (H₂O₂)/p-aminophenol (p-AP) production and lomefloxacin (LOM) degradation were fabricated via a strategy of merging 2D MoS₂ nanosheets into the nano-leaves of 3D CoMoS₄ micro-flowers. MoS₂@CoMoS₄ as a photocathode provides a green, economic and efficient route to achieve photoelectric-driven high productivity toward H₂O₂ (about 205 μM of H₂O₂ was produced under irradiation for 120 min) and p-AP (the corresponding p-AP yield was about 83% under illumination for 180 min) by using 5.0 mg of catalyst without any co-catalyst, while as a photoanode it also exhibits enhanced PEC performance for LOM oxidative degradation. The improved photoelectro-chemical redox activity is primarily attributed to the formation of a Z-scheme charge-transfer path, which can restrain the recombination of charges and lead to significantly enhanced redox ability of excited e⁻ and h⁺. The unique 2D/3D hierarchical MoS₂@CoMoS₄ flower-shaped arrays can economically achieve maximal harvesting of solar energy and full-spectrum light absorption, and provide more active sites, thus synergistically enhancing the catalytic performance. This work is instructive for the design of efficient bifunctional photoelectrocatalysts for meeting demands for chemical resources and concerns about environmental remediation through constructing a Z-scheme heterostructure photoelectrocatalyst.