Photocatalytic Performance Of Bi₁₉X₃S₂₇?x=Cl,Br,I? Nanomaterials

It's urgent to seek clean and sustainable substitute energy due to the increasingly serious environmental pollution and energy crisis.Solar energy is green and inexhaustible as the ideal alternative energy.Photocatalytic technology can effectively utilize the sunlight to achieve environmental purification and energy conversion,thus it has a broad application prospect.However,many reported photocatalysts have low photocatalytic activity due to their narrow response range and low quantum efficiency.Therefore,the research on high-performance photocatalysts has always been a hot topic in the field of photocatalysis.This paper focuses on the study of bismuth halide sulfide Bi₁₉X₃S₂₇?X=Cl,Br,I?and its heterojunction materials in the field of photocatalysis,mainly around the following aspects:?1?The single crystal Bi₁₉Cl₃S₂₇ nanorods were firstly synthesized by simple one-step solvothermal method.The as-synthesized nanorods have regular morphology.The growth mechanism of Bi₁₉Cl₃S₂₇ was studied by adjusting the reaction time.The results showed that Bi₁₉Cl₃S₂₇ photocatalyst can effectively degrade the common dye rhodamine B and reduce the poisonous hexavalent chromium,and the performance is better than the common photocatalysts,such as BiOCl,P25,WO₃ in photocatalytic Cr?VI?reduction.The active components and photocatalytic mechanism of Bi₁₉Cl₃S₂₇were discussed in detail.?2?We further took Bi₁₉Cl₃S₂₇ as research project,a common transition metal disulfide?MoS₂?was selected as the co-catalyst,carbon was selected as the binder between MoS₂ and Bi₁₉Cl₃S₂₇,successfully synthesized the cactus-like MoS₂ and Bi₁₉Cl₃S₂₇ heterojunction by solvothermal route.The special structure of this heterogeneous catalyst system was analyzed in detail,the Bi₁₉Cl₃S₂₇ is the backbone just like the stain of cactus,the MoS₂ is vertically standed on the surface of Bi₁₉Cl₃S₂₇.Carbon is tached between the Bi₁₉Cl₃S₂₇ and MoS₂,helpful for the carriers transporation.We analysed the change of photocatalytic activity by adjusting the amount of molybdenum disulfide,when the amount of MoS₂ is 5wt%,the heterojunction material owned the best activity than pure Bi₁₉Cl₃S₂₇,pure MoS₂,physical mixtures of Bi₁₉Cl₃S₂₇ and MoS₂,and precious metals platinum decorated Bi₁₉Cl₃S₂₇.Feasible photocatalytic reaction mechanism was proposed by studying the transport path between Bi₁₉Cl₃S₂₇ and MoS₂.The design concept of this heterojunction catalyst has a good universality and can give other catalyst design some inspiration.?3?Bismuth chloridesulfide,bismuth bromidesulfide and bismuth iodosulfide were synthesized without any protectant by solvothermal method.We compared the difference of morphology structure,physical properties and photocatalytic hydrogen production ability of Bi₁₉Cl₃S₂₇,Bi₁₉Br₃S₂₇ and?Bi?Bi₂S₃?₉I₃?_0.667.Bismuth bromosulfide was used as the representative material to study the synergistic effect of Bi elemental substance and sulfur vacancy on the photocatalytic hydrogen production performance.This series of photocatalysts have a broad application prospects in environment and energy conversion,and the series of photocatalysts were firstly studied in detail in this work.