摘要
为了揭示有机光催化剂激发态性质与其光催化剂性能之间的关系,以PDINH晶体为模型光催化剂,使用第一性原理方法对其基态和激发态进行理论研究。密度泛函计算得知,PDINH晶体的带隙约为1.61 eV,其价带和导带贡献都来自于C和O原子的2P轨道;含时密度泛函计算了PDINH晶体的紫外-可见光谱,使用电子-空穴分析方法对造成可见-红外响应的6种激发态进行分析,确定了激发类型,绘制了电子图、空穴图、电子-密度差分图,并计算了D、Sr、H、t,Ecoul、 HDI和EDI等7种指数。结果显示,晶态PDI的6种激发态虽然激发类型分可为n->π*和π->π*2类,但都属于电子局域激发,不利于电子-空穴分离,导致其光催化性能不理想,与实验结果吻合。
There are many reports about the design and performance of organic photocatalysts,but most of them focus on the relationship between the ground state structure and photocatalytic performance.In theory,the properties of photocatalysts are mainly related to the excited state rather than the ground state.In view of this,the ground state and excited state of PDINH crystal were studied theoretically by first-principles method using PDINH crystal model photocatalyst.The density functional calculation shows that the band gap of PDINH crystal is about 1.61 eV,and its valence band and conduction band contributions come from the 2P orbital of C and O atoms.The UV-vis spectrum of PDINH crystal was obtained by time-dependent density functional calculation,and six excited states causing visible-infrared response were analyzed by electron-hole analysis method.The excitation types were determined,and electron diagrams,hole diagrams and electron-density difference diagrams were drawn.D,Sr,H,T,Ecoul,HDI and EDI indices were calculated.The results show that the excitation types of the six excited states can be divided into n-π* and π-π*.However,all of them belong to local electron excitation,which is not corducive to electron-hole separation,resulting in unsatifactory photocatalytic performance,which is consistent with the experiment results.
作者
张梦源
朱炜
王嘉伟
车远军
袁双平
刘斌
李庆
ZHANG Mengyuan;ZHU Wei;WANG Jiawei;CHE Yuanjun;YUAN Shuangping;LIU Bin;LI Qing(School of Environmental and Chemical Engineering,Xi’an Polytechnic University,Xi’an 710048,China;Xi’an Dingxin Boyuan Energy Technology Co.Ltd.,Xi’an 710048,China)
出处
《纺织高校基础科学学报》
CAS
2023年第3期21-29,共9页
Basic Sciences Journal of Textile Universities
基金
国家自然科学基金面上基金(22078253)
陕西省自然科学基础研究面上项目(2022JM-092)
西安市科技计划先进制造业技术攻关项目(21XJZZ0015)
西安市碑林区应用技术研发项目(GX2212)。
关键词
PDINH
密度泛函
含时密度泛函
光催化剂
PDINH
density functional
time-dependent density functional
photocatalyst