用于高效水分解的聚合氮化碳光电极的熔体相与气相一体化沉积  

Integrated molten and vapor condensation of polymeric carbon nitride photoelectrode towards efficient water splitting

作　　者：王语晴 司文平 谭皓天 谢志强 王立群 狄璐 梁骥 侯峰 Yuqing Wang;Wenping Si;Haotian Tan;Zhiqiang Xie;Liqun Wang;Lu Di;Ji Liang;Feng Hou(Key Laboratory of Advanced Ceramics and Machining Technology,Ministry of Education,School of Materials Science and Engineering,Tianjin University,Tianjin 300350,China;Applied Physics Department,College of Physics and Materials Science,Tianjin Normal University,Tianjin 300387,China;School of Materials Science and Engineering,Nankai University,Tianjin 300350,China)

机构地区：[1]Key Laboratory of Advanced Ceramics and Machining Technology,Ministry of Education,School of Materials Science and Engineering,Tianjin University,Tianjin 300350,China [2]Applied Physics Department,College of Physics and Materials Science,Tianjin Normal University,Tianjin 300387,China [3]School of Materials Science and Engineering,Nankai University,Tianjin 300350,China

出　　处：《Science China Materials》2023年第2期623-633,共11页中国科学（材料科学（英文版）

基　　金：supported by the National Natural Science Foundation of China(22002107,21905202,22179093 and 21905144);Tianjin University(2021XZC-0052);the Science and Technology Plan Project of Qinghai Province(2021-zj-702)。

摘　　要：氮化碳在光催化悬浮液体系的应用受到了广泛关注,但高质量氮化碳薄膜的制备技术仍处于初级阶段,限制了其在光电催化领域的应用.本文采用小分子双氰胺和硫脲为前驱体,实现了熔体相和气相一体化沉积制备高性能的氮化碳薄膜光电极.原位的沉积技术赋予氮化碳薄膜复合结构,包括具有合适厚度利于光吸收的多孔厚膜区域和具有较高碳/氮比利于电荷传输的致密薄膜区域.本文详细阐述了氮化碳薄膜沉积的各个阶段和前驱体双氰胺和硫脲在薄膜沉积过程的功能.独特的沉积方式和复合结构使得制备的氮化碳薄膜在光电催化水分解领域表现出优异的性能,在1.23 VRHE,0.1 mol L^(-1)NaOH电解液中表现出140μA cm^(-2)的光电流密度,相较于文献报道的熔体相沉积和气相沉积制备的氮化碳光阳极具有更高的竞争力.这种熔体相和气相沉积一体化策略对理解氮化碳光阳极的生长过程具有启发意义.Polymeric carbon nitride(PCN)has received extensive attention in suspension photocatalysis,whereas the preparation of high-quality PCN film is still at an initial stage,limiting its practical application in photoelectrochemical(PEC)systems.Herein,an integrated molten and vapor condensation route is realized using small molecule precursors dicyandiamide(DCDA)and thiourea(TU)to form PCN film photoelectrode with high performance.The in-situ deposition route endows the PCN film with a composite structure including a thick porous zone with suitable thickness for light absorption and thin compact zone with a higher C/N ratio for better charge transportations.The growth of the specific film and the functions of precursors DCDA and TU are investigated in detail.Owing to the unique condensation route and film structure,this PCN film exhibits excellent performance in PEC water splitting with a photocurrent density of ca.140μA cm^(-2)in 0.1 mol L^(-1)NaOH electrolyte at 1.23VRHE,which is competitive or higher than the results of the reported PCN photoanodes prepared by the molten-mediated method and thermal vapor condensation.The integrated molten and vapor condensation strategy is enlightening for comprehending the growth of PCN photoelectrodes.

关 键 词：氮化碳薄膜 气相沉积 复合结构 光电极 一体化策略 沉积技术 双氰胺 光电催化 

分 类 号：TQ116.2[化学工程—无机化工] O643.36[理学—物理化学]