Preparation Of Anatase/Rutile TiO₂ Photocatalyst With Interfacial Hydrogenation And MoS₂ Loading And Their Photoelectrochemical Hydrogen Production Performance

With the development of society,people pay more attention to energy and ecological environment.Photocatalytic materials have great potential in solving energy shortage and environmental pollution.The practical technology of photocatalysis for efficient utilization of sunlight has always been a dream pursued by people.Titanium dioxide is considered as an ideal photocatalytic material due to its low price,green environmental protection and stable performance.However,due to the rapid recombination of photogenerated carriers,the photocatalytic efficiency is still relatively low,which greatly affects the application of titanium dioxide.Based on this,in this paper,titanium dioxide nanorod array?RTNA?was used as the substrate to carry out the following research:?1?A new photoelectrode with interfacial hydrogenation of anatase/rutile titanium dioxide thin film?A-H-RTNA?was successfully designed and synthesized for the first time through hydrothermal synthesis and hydrogenation branching growth.The structure characterizations indicated that the hydrogenated interfaces between anatase-branches and rutile titanium dioxide nanorod hold appropriate oxygen vacancies and Ti³⁺.The new energy levels of oxygen vacancy and Ti-OH lie below the band edge positions of conduction band and valance band of rutile titanium dioxide nanorod,respectively.The matching energy levels between anatase-branches and hydrogenated rutile-nanorod obviously reduce the recombination of the photogenerated carriers,resulting in a superior photoelectrochemical?PEC?hydrogen production performance.At the applied bias potential of 1.02 V bias,the hydrogen evolution rate on A-H-RTNA photoelectrode for PEC water splitting reached 136.5 mol cm^-2 h^-1(1365 mmol m^-2 h^-1),which was 20.0 times of pure RTNA and 2.1 times of H-A-RTNA with surface hydrogenated heterogeneous structure,respectively,and showed high stability.This work provides a new perspective for studying titanium dioxide photocatalyst with interfacial hydrogenation heterogeneous structure.?2?A new type of MoS₂/A-H-RTNA electrode material was prepared by direct hydrothermal method,in which 1T and 2H mixed phase MoS₂ was loaded on the interfacial hydrogenated anatase/rutile heterophase titanium dioxide sheets.The electrochemical tests showed that the prepared material exhibited higher carrier density,lower photoelectron-hole recombination rate and higher conductivity than Pt/A-H-RTNA.The reason is that 1T-MoS₂with metal properties loaded on A-H-RTNA has more active sites and lower charge transfer resistance than Pt loaded on A-H-RTNA.Under the bias potential of-0.4 V,the optimized16MoS₂/A-H-RTNA as photocathode had a PEC hydrogen production rate of 1840 mmol m^-2h^-1,which was 2.9 and 2.2 times of A-H-RTNA(625 mmol m^-22 h^-1)and Pt/A-H-RTNA(848mmol m^-22 h^-1),respectively,and had good stability.Here,an innovative PEC hydrogen production system without noble-metal was constructed using 16MoS2/A-H-RTNA thin film as the counter electrode to replace Pt electrode in PEC system.The same A-H-RTNA electrode was used as working electrode for PEC hydrogen production test.The results showed that the PEC hydrogen production activity of titanium dioxide-based non-noble metal electrode can reach 75%of that of pure Pt electrode.In this study,a PEC hydrogen production system without any precious metals was developed,predicting a promising application.