氧化锌/锡酸锌/二氧化锡双异质结纳米阵列的构建及其光电性能  

Construction and Photoelectrochemical Performance of Zinc Oxide/Zinc Stannate/Tin Dioxide Double Heterojunction Nanoarray

作　　者：周龙杰 王航 刘硕 李丽华[1,2] 黄金亮 ZHOU Longjie;WANG Hang;LIU Shuo;LI Lihua;HUANG Jinliang(School of Materials Science and Engineering,Henan University of Science and Technology,Luoyang 471023,Henan,China;Provincial and Ministerial Co-construction of Collaborative Innovation Center for Non-ferrous Metal New Materials and Advanced Processing Technology,Luoyang 471023,Henan,China)

机构地区：[1]河南科技大学材料科学与工程学院,河南洛阳471023 [2]有色金属新材料与先进加工技术省部共建协同创新中心,河南洛阳471023

出　　处：《硅酸盐学报》2024年第7期2308-2315,共8页Journal of The Chinese Ceramic Society

基　　金：高端外国专家项目(GDW2017410125)。

摘　　要：高性能的电子传输传输层对提升钙钛矿太阳能电池的光电转化效率具有至关重要的作用。基于表面修饰的方法,采用旋涂法在ZnO纳米阵列上制备Zn_(2)SnO_(4)钝化层,再通过水热法原位自生长SnO_(2)构建出ZnO/Zn_(2)SnO_(4)/SnO_(2)双异质结纳米阵列。利用X射线衍射、场发射扫描电镜、透射电子显微镜对异质结的物相、形貌进行了观察和分析,并通过电化学工作站对其光电性能进行了测试。结果表明:Zn_(2)SnO_(4)和SnO_(2)都成功负载在ZnO上,三者之间交错的能带结构所形成的双Ⅱ型异质结进一步提高了光生电子–空穴对分离效率,使得ZnO/Zn_(2)SnO_(4)/SnO_(2)双异质结纳米阵列的电流密度以及光电流较ZnO得到了明显的改善,同时电荷转移电阻从22403Ω降低至3131Ω,载流子浓度从1.22×10^(19)cm^(–3)降低至1.18×10^(18)cm^(–3),光电性能提升明显。Introduction As an important part of perovskite solar cells,the electron transport layer plays a role in transporting electrons and blocking holes,having an impact on the performance of perovskite cells.ZnO is a promising electron transport layer (ETL) material because of its high electron mobility,easy synthesis,low-temperature preparation and low cost.However,the chemical properties of ZnO are unstable,and the surface defects are easy to form recombination centers,leading to the decline of electron extraction and transfer efficiency,and surface residual groups destroy the perovskite structure and reduce the stability of perovskite materials,resulting in the deterioration of device performance.Therefore,selecting a suitable modification layer to improve the stability of ZnO plays an important role in improving the performance of ZnO and perovskite batteries.Methods ZnO/Zn_(2)SnO_(4) NAs was prepared on ZnO NAs surface by a spin-coating method to passivate ZnO surface defects and residual groups.ZnO/Zn_(2)SnO_(4)/SnO_(2) NAs was formed via in-situ growth of a layer of SnO_(2) by a hydrothermal method to improve the stability of ZnO.The phase and morphology of the heterojunction were analyzed by X-ray diffraction (XRD),scanning electron microscopy(SEM) and transmission electron microscopy (TEM).The photoelectric performance was measured in electrochemical workstation,in which the photoelectric response ability of the nanoarray was characterized by linear sweep voltammetry.The separation performance of photogenerated electrons and holes in nanoarrays was analyzed via the change of photocurrent.The charge transfer resistance was determined by electrochemical impedance spectroscopy.The conductive type of the semiconductor was determined via the Mott-Schottky test,and the passivation effect of Zn_(2)SnO_(4) and SnO_(2) on the ZnO surface defects was reflected by the carrier concentration.Results and discussion The results by XRD,SEM and TEM show that Zn_(2)SnO_(4) and SnO_(2) are coated on ZnO nanoarrays.Zn_(2)SnO_(4)

关 键 词：氧化锌/锡酸锌/二氧化锡 双异质结 载流子分离 光电性能 

分 类 号：O611.4[理学—无机化学] O649.1[理学—化学] O649.4