本文主要研究内容
作者贺勇（2019）在《新型二维材料及其异质结的电子结构与光催化性能的第一性原理研究》一文中研究指出：半导体光催化剂在可见光的照射下可以分解水制备氢气,这是解决当前能源短缺和环境污染问题的有效途径。尽管许多理论和实验研究已经合成了众多的光催化剂,但是产生氢气的效率依然比较低。近年来,新型的二维（2D）材料表现出了优异的物理和化学性能,为改善光催化性能开启了新的研究思路。其中,构建异质结光催化剂可以增强对可见光的吸收和降低电子和空穴的复合,极大的提升了光催化性能,这也是当前能源领域的研究热点。本文采用第一性原理计算方法系统研究了新型的2D g-C3N4/InSe异质结的电子结构和光催化机理,应变调控对单层SiC材料的几何结构和电子性质的影响以及SiC/InSe纳米复合材料的光催化性能。主要研究内容总结如下:2D g-C3N4/InSe异质结是一种直接带隙半导体材料,晶格失配率低于1.5%,形成能为-1.85 eV,具有稳定的结构。异质结禁带宽度为1.93 eV,对应有较宽的可见光吸收范围,吸收系数高达105cm-1。且表现出Ⅱ型能带对齐,导带和价带的带偏置分别为0.74和0.78 eV,说明光生空穴从InSe层转移到了g-C3N4层,而电子则与之相反,表明电子和空穴很好的实现了空间分离。同时,由于单层InSe是间接带隙半导体材料,能够极大限度地减小电子和空穴的复合率,且异质结中电子和空穴的迁移率分别为104和102cm2V-1s-1,这些均表明,2D g-C3N4/InSe异质结具有良好的光催化性能,是一种性能优异的新型光催化材料。采用第一性原理计算了单层SiC的声子谱和电子结构。声子谱计算表明,频率都是正值,说明单层SiC在动力学上是稳定的。进一步计算了能带结构,表明SiC是一种直接带隙的宽禁带半导体,GW带隙值为3.73eV。采用GGA-PBE泛函,研究了单、双轴应变对单层SiC电子性质的影响。结果表明,在单x轴压缩应变,单y轴应变以及双轴压缩应变调控下,SiC均出现了由直接带隙到间接带隙的转变,而单x轴和双轴的拉伸应变下SiC依然是直接带隙半导体。单轴应变下带隙值几乎都是减小的,双轴压缩应变到拉伸应变下带隙值呈现由大到小的变化趋势,变化范围为2.862.11 eV。以单层SiC材料为基础,构建了SiC/InSe纳米复合材料光催化剂,研究了几何结构、电子性质和光催化性能。计算表明,该材料晶格失配率低于1.3%,形成能为-4.32 eV,表明异质结是稳定的。能带计算表明,2D SiC/InSe异质结是带隙值为1.78 eV的间接带隙半导体材料,故具有较大的可见光吸收范围,吸收强度高达2×105cm2V-1s-1。异质结中光生空穴和电子分别位于SiC和InSe层,构成了Ⅱ型能带对齐,实现了空穴和电子在空间上的分离。另外,异质结中形成了由InSe指向SiC的内建电场,有效的降低了电子和空穴的复合。综上,设计的SiC/InSe异质结有利于光催化效率的提高。
Abstract
ban dao ti guang cui hua ji zai ke jian guang de zhao she xia ke yi fen jie shui zhi bei qing qi ,zhe shi jie jue dang qian neng yuan duan que he huan jing wu ran wen ti de you xiao tu jing 。jin guan hu duo li lun he shi yan yan jiu yi jing ge cheng le zhong duo de guang cui hua ji ,dan shi chan sheng qing qi de xiao lv yi ran bi jiao di 。jin nian lai ,xin xing de er wei （2D）cai liao biao xian chu le you yi de wu li he hua xue xing neng ,wei gai shan guang cui hua xing neng kai qi le xin de yan jiu sai lu 。ji zhong ,gou jian yi zhi jie guang cui hua ji ke yi zeng jiang dui ke jian guang de xi shou he jiang di dian zi he kong xue de fu ge ,ji da de di sheng le guang cui hua xing neng ,zhe ye shi dang qian neng yuan ling yu de yan jiu re dian 。ben wen cai yong di yi xing yuan li ji suan fang fa ji tong yan jiu le xin xing de 2D g-C3N4/InSeyi zhi jie de dian zi jie gou he guang cui hua ji li ,ying bian diao kong dui chan ceng SiCcai liao de ji he jie gou he dian zi xing zhi de ying xiang yi ji SiC/InSena mi fu ge cai liao de guang cui hua xing neng 。zhu yao yan jiu nei rong zong jie ru xia :2D g-C3N4/InSeyi zhi jie shi yi chong zhi jie dai xi ban dao ti cai liao ,jing ge shi pei lv di yu 1.5%,xing cheng neng wei -1.85 eV,ju you wen ding de jie gou 。yi zhi jie jin dai kuan du wei 1.93 eV,dui ying you jiao kuan de ke jian guang xi shou fan wei ,xi shou ji shu gao da 105cm-1。ju biao xian chu Ⅱxing neng dai dui ji ,dao dai he jia dai de dai pian zhi fen bie wei 0.74he 0.78 eV,shui ming guang sheng kong xue cong InSeceng zhuai yi dao le g-C3N4ceng ,er dian zi ze yu zhi xiang fan ,biao ming dian zi he kong xue hen hao de shi xian le kong jian fen li 。tong shi ,you yu chan ceng InSeshi jian jie dai xi ban dao ti cai liao ,neng gou ji da xian du de jian xiao dian zi he kong xue de fu ge lv ,ju yi zhi jie zhong dian zi he kong xue de qian yi lv fen bie wei 104he 102cm2V-1s-1,zhe xie jun biao ming ,2D g-C3N4/InSeyi zhi jie ju you liang hao de guang cui hua xing neng ,shi yi chong xing neng you yi de xin xing guang cui hua cai liao 。cai yong di yi xing yuan li ji suan le chan ceng SiCde sheng zi pu he dian zi jie gou 。sheng zi pu ji suan biao ming ,pin lv dou shi zheng zhi ,shui ming chan ceng SiCzai dong li xue shang shi wen ding de 。jin yi bu ji suan le neng dai jie gou ,biao ming SiCshi yi chong zhi jie dai xi de kuan jin dai ban dao ti ,GWdai xi zhi wei 3.73eV。cai yong GGA-PBEfan han ,yan jiu le chan 、shuang zhou ying bian dui chan ceng SiCdian zi xing zhi de ying xiang 。jie guo biao ming ,zai chan xzhou ya su ying bian ,chan yzhou ying bian yi ji shuang zhou ya su ying bian diao kong xia ,SiCjun chu xian le you zhi jie dai xi dao jian jie dai xi de zhuai bian ,er chan xzhou he shuang zhou de la shen ying bian xia SiCyi ran shi zhi jie dai xi ban dao ti 。chan zhou ying bian xia dai xi zhi ji hu dou shi jian xiao de ,shuang zhou ya su ying bian dao la shen ying bian xia dai xi zhi cheng xian you da dao xiao de bian hua qu shi ,bian hua fan wei wei 2.862.11 eV。yi chan ceng SiCcai liao wei ji chu ,gou jian le SiC/InSena mi fu ge cai liao guang cui hua ji ,yan jiu le ji he jie gou 、dian zi xing zhi he guang cui hua xing neng 。ji suan biao ming ,gai cai liao jing ge shi pei lv di yu 1.3%,xing cheng neng wei -4.32 eV,biao ming yi zhi jie shi wen ding de 。neng dai ji suan biao ming ,2D SiC/InSeyi zhi jie shi dai xi zhi wei 1.78 eVde jian jie dai xi ban dao ti cai liao ,gu ju you jiao da de ke jian guang xi shou fan wei ,xi shou jiang du gao da 2×105cm2V-1s-1。yi zhi jie zhong guang sheng kong xue he dian zi fen bie wei yu SiChe InSeceng ,gou cheng le Ⅱxing neng dai dui ji ,shi xian le kong xue he dian zi zai kong jian shang de fen li 。ling wai ,yi zhi jie zhong xing cheng le you InSezhi xiang SiCde nei jian dian chang ,you xiao de jiang di le dian zi he kong xue de fu ge 。zeng shang ,she ji de SiC/InSeyi zhi jie you li yu guang cui hua xiao lv de di gao 。
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论文作者分别是来自内蒙古师范大学的贺勇，发表于刊物内蒙古师范大学2019-07-11论文，是一篇关于异质结论文,单层论文,异质结论文,电子结构论文,光催化性能论文,第一性原理计算论文,内蒙古师范大学2019-07-11论文的文章。本文可供学术参考使用，各位学者可以免费参考阅读下载，文章观点不代表本站观点，资料来自内蒙古师范大学2019-07-11论文网站，若本站收录的文献无意侵犯了您的著作版权，请联系我们删除。
标签：异质结论文; 单层论文; 电子结构论文; 光催化性能论文; 第一性原理计算论文; 内蒙古师范大学2019-07-11论文;