共查询到17条相似文献，搜索用时 62 毫秒
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钙钛矿薄膜的晶粒尺寸对器件性能影响很大。采用湿润性不同的空穴传输层以及不同浓度的CH3NH3I（MAI）溶液,使用热退火和溶剂气氛退火的方法制备出CH3NH3PbI3薄膜及相应电池。测量了不同制备条件的钙钛矿薄膜的X射线衍射、扫描电子显微镜、光致发光谱,以及器件的电流密度-电压曲线。结果表明,溶剂气氛退火可以有效地增大薄膜的晶粒尺寸,提高器件的电流密度;较高浓度的MAI能将PbI2完全转化为CH3NH3PbI3,增大晶粒尺寸;不湿润的功函数更高的空穴传输层有利于电池效率的提高。制备了最高效率为13.3%的CH3NH3PbI3钙钛矿电池,为制备更大晶粒的钙钛矿薄膜与更高效率的钙钛矿太阳电池奠定了基础。 相似文献
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利用一步溶液法在p型Si衬底上生长有机/无机杂化钙钛矿CH3NH3PbI3薄膜,构成CH3NH3PbI3/p-Si异质结。利用原子力显微镜(AFM)、扫描电子显微镜(SEM)对薄膜形貌和结构进行表征,通过无光照和有光照条件下的电流-电压(I-V)、电容-电压(C-V)测试对异质结的光电特性进行研究。I-V测试结果显示CH3NH3PbI3/p-Si异质结具有整流特性,正反偏压为±5V时,整流比大于70,并在此异质结上观察到了光电转换现象,开路电压为10mV,短路电流为0.16uA。C-V测试结果显示Ag/CH3NH3PbI3/p-Si异质结具有与MIS(金属-绝缘层-半导体)结构相似的C-V特性曲线,与理想MIS的C-V特性曲线相比,异质结的C-V曲线整体沿电压轴向正电压方向平移。C-V特性曲线的这种平移表明Ag/CH3NH3PbI3/p-Si异质结界面存在界面缺陷,CH3NH3PbI3层也可能存在固定电荷。这种界面缺陷是导致CH3NH3PbI3/p-Si异质结开路电压的大幅度降低的重要原因。此外,CH3NH3PbI3薄膜的C-V测试结果显示其具有介电非线性特性,其介电常数约为4.64。 相似文献
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在酸性溶液中利用恒电位沉积法在导电玻璃(ITO)上沉积Cu2O薄膜,并以KC1为添加剂对其进行掺杂,采用场发射扫描电子显微镜(FESEM)和X射线衍射谱(XRD)等手段研究了氯掺杂对Cu2O表面形貌和晶体结构的影响.紫外-可见吸收光光谱确定得到的Cu2O和Cl掺杂Cu2O(Cu2 O-C1)样品的禁带宽度分别为1.98和1.95 eV.根据表面光电压谱和相位谱,掺杂前后的Cu2O均为n型,Cu2 O-C1有更强的表面光电压响应.场诱导表面光电压谱结果表明未掺杂C1的Cu2O在加负偏压时易形成反型层;氯离子的掺杂引入杂质能级可以提高n型导电性.光电化学性能测试发现,以Cu2O、Cu2 O-Cl为光阳极组成的光化学太阳电池,在大气质量AM 1.5G、100 mW/cm2标准光强作用下光电转换效率分别为0.12％和0.51％. 相似文献
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结合水热法和阳极氧化法合成了Sb2S3/TiO2纳米管异质结阵列,采用场发射扫描电子显微镜、X射线衍射谱表征了异质结阵列的形貌和晶体结构.暗态下的电流-电压曲线表明Sb2S3/TiO2纳米管异质结阵列具有整流效应.相比于纯的TiO2纳米管阵列,Sb2S3/TiO2纳米管异质结阵列的光电性能有了显著地提升:在AM1.5标准光强作用下,光电转换效率从0.07％增长到0.40％,表面光电压响应范围从紫外光区拓宽至可见光区.结合表面光电压谱和相位谱,分析了Sb2S3/TiO2纳米管异质结阵列中光生载流子的分离和传输性能. 相似文献
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近年来研究表明,通过增大晶粒尺寸和减少晶界数量可以有效减小钙钛矿太阳能电池的漏电流和增大并联电阻,极大地增加其能量转化效率。溶剂热处理工艺是一种利用溶解再结晶的原理增大薄膜晶粒的实用工艺,可用于制备大晶粒高质量的多晶薄膜。本文制备了不同溶剂热处理时长的旋涂制备的钙钛矿CH3NH3PbI3薄膜,利用SEM和XRD分析了其形貌和晶体结构的变化,探索了薄膜晶粒形貌与电池性能的对应关系,应用优化后的溶剂热处理工艺成功制备出大晶粒、高性能的钙钛矿薄膜。实验表明,溶剂热处理法制备的钙钛矿CH3NH3PbI3薄膜平均晶粒尺寸接近3μm,较普通热处理方法制备的薄膜晶粒尺寸(约300 nm)有显著增大。 相似文献
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Sb2O3掺杂对ZnO薄膜光吸收性能的影响 总被引：1，自引：0，他引：1
采用RF磁控溅射技术制备了Sb2O3掺杂ZnO薄膜,通过X射线光电子能谱仪（XPS）、X射线衍射仪（XRD）和紫外-可见光（UV-Vis）分光光度计研究了Sb2O3对ZnO薄膜结构和光吸收性能的影响。结果表明：Sb2O2的掺杂影响了ZnO的原子和电子状态、晶粒的生长方式和光吸收性能。薄膜中Sb以多种形态存在：替位原子和化合物（Sb2O3、Zn,Sb2O14）等,ZnO呈混晶方式生长;随着Sb含量的增加,其引起的晶格畸变和次晶相的含量逐渐增加;掺杂薄膜在远紫外（UVA）波段的吸收显著增强,UV吸收峰变窄,强度增大,吸收边变得陡峭且向短波方向移动达5nm,在Vis波段的吸收有所增强。 相似文献
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采用旋涂法与水热法在掺氟二氧化锡(FTO)上制备了Ce掺杂Bi2S3/Fe2O3(Ce-Bi2S3/Fe2O3)异质结,对样品的组成、形貌及其光电性能进行了研究分析.结果 显示,Ce-Bi2S3/Fe2O3的X射线衍射(XRD)图谱中各衍射峰位与Bi2S3/Fe2O3相似,无新的相产生,但在2θ为24.92°(130)与28.65°(211)的衍射峰强度有所降低,而在2θ为35.65°(110)时有所增强;在Ce-Bi2S3/Fe2O3的X射线能谱(EDS)中发现了Ce元素.光电性能测试结果表明,在模拟太阳光的照射下Ce-Bi2S/Fe2O3的光电压为0.347 V,比Bi2S3/Fe2O3 (0.281 V)提高了23.5％;光电流密度达到2.31 mA·cm-2,比Bi2S3/Fe2O3 (0.53 mA·cm-2)提高了约3.36倍;电化学阻抗谱(EIS)显示,在光照下Ce-Bi2S3/Fe2O3具有最低的界面阻抗,表明Ce-Bi2S3/Fe2O3中的载流子被更有效地分离和转移. 相似文献
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Guang‐Xing Liang Ping Fan Jing‐Ting Luo Di Gu Zhuang‐Hao Zheng 《Progress in Photovoltaics: Research and Applications》2015,23(12):1901-1907
In this work, a new method of fabricating organolead halide perovskite CH3NH3PbI3 thin film by unisource thermal evaporation was proposed, which ensured high‐quality film with composition, crystal‐structure homogeneity, full surface coverage, well‐defined grain structure, high crystalline, and reproducibility, suggesting its promising applicability for significant optimization in efficient. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
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Yurou Zhang Dohyung Kim Jung-Ho Yun Jongchul Lim Min-Cherl Jung Xiaoming Wen Jan Seidel Eunyoung Choi Mu Xiao Tengfei Qiu Miaoqiang Lyu EQ Han Mehri Ghasemi Sean Lim Henry J. Snaith Jae Sung Yun Lianzhou Wang 《Advanced functional materials》2021,31(50):2105542
Organometal perovskite single crystals have been recognized as a promising platform for high-performance optoelectronic devices, featuring high crystallinity and stability. However, a high trap density and structural nonuniformity at the surface have been major barriers to the progress of single crystal-based optoelectronic devices. Here, the formation of a unique nanoisland structure is reported at the surface of the facet-controlled cuboid MAPbI3 (MA = CH3NH3+) single crystals through a cation interdiffusion process enabled by energetically vaporized CsI. The interdiffusion of mobile ions between the bulk and the surface is triggered by thermally activated CsI vapor, which reconstructs the surface that is rich in MA and CsI with reduced dangling bonds. Simultaneously, an array of Cs-Pb-rich nanoislands is constructed on the surface of the MAPbI3 single crystals. This newly reconstructed nanoisland surface enhances the light absorbance over 50% and increases the charge carrier mobility from 56 to 93 cm2 V−1 s−1. As confirmed by Kelvin probe force microscopy, the nanoislands form a gradient band bending that prevents recombination of excess carriers, and thus, enhances lateral carrier transport properties. This unique engineering of the single crystal surface provides a pathway towards developing high-quality perovskite single-crystal surface for optoelectronic applications. 相似文献
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Xiaoning Zhao Zhongqiang Wang Wentong Li Shaowu Sun Haiyang Xu Peng Zhou Jiaqi Xu Ya Lin Yichun Liu 《Advanced functional materials》2020,30(17)
Organic–inorganic hybrid perovskite memristors with high resistive‐switching (RS) reliability and low power consumption are crucial for high‐density storage and high‐efficiency neuromorphic computing. However, the current overshoot in the electroforming process generally induces overgrowth of conductive filaments (CFs) and degrades the RS performance. Here, a simple photo‐assisted electroforming (PAE) method to suppress the current overshoot, in which the visible light irradiation is introduced into the initial electroforming process, is proposed for the first time. As a result, a reliable memristor with reduced RS fluctuation and enhanced cycling endurance is obtained, and also, the low operating current of 0.06 mA and low powerconsumption of 0.12 mW are achieved, which are about one order of magnitude lower than those of most reported hybrid perovskite‐based memristors. Further experimental evidence indicates that light irradiation plays dual roles: 1) the light‐induced lowering of iodide migration barrier leads to a significant reduction of overshoot current and forming voltage; 2) the enhanced local photoconductivity of the perovskite film shares the overshoot current through the CFs. Both factors limit the total quantity of vacancy defects generated in the electroforming process, thus preventing undesirable overgrowth of the CFs. The present PAE strategy has promise for developing high‐performance memristors. 相似文献
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Yangyang Wang Tianhao Li Zengrong Li Sen Wang Xianyu Deng 《Advanced functional materials》2019,29(45)
Laminated multilayers of perovskite films with different optical and electronic characteristics will easily realize high‐performance optoelectronic devices because it is widely demonstrated that differential distribution of film properties in the vertical direction of devices plays particularly important roles in device performance. However, the existing laminated perovskite films are hardly prepared by a solution process because there is no solvent with sufficient selectivity of solubility for different perovskite materials. Here, it is demonstrated that aniline (AN) has a largely different solubility toward the perovskite MAPbI3 and the MAPbI3 blend with an additive of hydrochloride diethylammonium chloride. By using AN as the solvent in the perovskite precursor solution, two laminated perovskite layers with different crystal size and optical and electrical characteristics are achieved. Inverted perovskite solar cells with the laminated films as active layers achieve an averaged power conversion efficiency of 20.65% originating from the high VOC 1.112 V and fill factor of 80.8%. The devices maintain 98% efficiency after 400 h under 65% RH. This work provides a very simple and feasible method for production of laminated perovskite films to achieve high‐performance perovskite solar cells. 相似文献
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Zhi Zheng Fuwei Zhuge Yaguang Wang Jianbing Zhang Lin Gan Xing Zhou Huiqiao Li Tianyou Zhai 《Advanced functional materials》2017,27(43)
Broadband photodetectors based on TiO2 nanotubes (NTs) array have significant prospects in many fields such as environmental monitoring. Herein, a simple spin‐coating process is successfully adopted to incorporate MAPbI3 quantum dots (QDs) onto the surface of TiO2 NTs to form a heterostructure, extending the response range of TiO2 NT from ultraviolet to visible. Compared with pure TiO2 NTs, the heterostructure demonstrates an improvement of responsivity in visible range by three orders of magnitude, and maintains its response performance in the UV range simultaneously. The TiO2 NTs based heterostructure photodetectors demonstrate a relative fast and stable response in the 300–800 nm range and even have a reponsivity of 0.2 A W?1 at 700 nm. The photoelectric performance of the hybrid photodetector based on TiO2 NTs maintains well when exposed to moist air for 72 h or heated from room temperature to 100 °C. Moreover, such a TiO2 NTs/MAPbI3 QDs heterostructure device demonstrates excellent flexibility and high transparency (85%) in the 400–800 nm range, their photodetecting performance is well retained after 200 cycles of repeated bending at 90°. The present strategy that combines facile electrospinning and solution‐processed QDs may open a new avenue for wide range response and flexible devices construction. 相似文献