Pesticides refer to the chemicals to regulate plant growth and control pests used in agriculture. However, the extensive use of pesticides causes serious pollution that threatens the ecological environment and human health. Photocatalytic degradation of pesticides has become a promising way to deal with pesticide pollution. In this review, pesticides are classified according to the different targets and chemical structures. The recent developments on semiconductor-based photocatalysts including metal oxides, metal oxyhalides, carbon nitrides, and metal sulfides were reviewed for degradation of pesticides. Importantly, several modification strategies to improve the photocatalytic performance are described such as doping, heterojunction construction, and defect engineering, with special emphasis on anchoring single atom catalyst. Moreover, extensive efforts should be made to in-depth understand the photodegradation mechanism by monitoring key intermediates. Our perspectives on the key challenges and future directions of developing high-performance semiconductor-based photocatalysts for pesticide degradation are elaborated.

Electrocatalytic water splitting into hydrogen is one of the most favorable approaches to produce renewable energy. MoS₂ has received great research attention for both hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) due to its unique structure and ability to be chemically modified, enabling its electrocatalytic activity to be further enhanced or made comparable to that of Pt-based materials. In this review, we discuss the important fabrication approaches of MoS₂ ultrathin nanosheet (MoS₂ NS) to improve the intrinsic catalytic activity of bulk MoS₂. Moreover, several modification strategies involve either morphology modulation or electron structural modulation to improve the charge transfer kinetics, including doping, vacancy, and heterojunction construction or single-atom anchor. Our perspectives on the key challenges and future directions of developing high-performance MoS₂-based electrocatalysts for overall water splitting are also discussed.