Defect-mediated successive ionic layer adsorption and reaction for constructing Sb2Te3/Ag2S heterojunction to boost hydrogen evolution reaction performance

As a sustainable and green technology for producing high-purity hydrogen, hydrogen evolution reaction (HER) has received extensive attention. The development of an electrocatalyst with good HER activity is the key to economic water electrolysis. Here, this work reports a defect-mediated successive ion layer adsorption and reaction method to construct Ag 2 S/irradiated Sb 2 Te 3 heterojunctions with good HER activity. First, ion irradiation is used to introduce a large number of defects into Sb 2 Te 3 . The defective Sb 2 Te 3 is continuously cyclically immersed in AgNO 3 solution and Na 2 S solution. Ag + and S 2- ions are adsorbed on the defect sites of Sb 2 Te 3 and deposited as Ag 2 S and the heterojunction of Ag 2 S/irradiated Sb 2 Te 3 is obtained. By this strategy, the electrochemical active surface area of the material is increased, reduces the charge transfer resistance, and improves the hydrophilicity of the material surface, thus exhibiting good HER activity. In this work, ion irradiation is used to regulate the surface defects of materials and then to regulate the growth of heterojunction to achieve the purpose of regulating the properties of material. The heterojunction growth method controlled by defect engineering can be widely used in the preparation of heterojunction materials in other energy and environmental fields.