Fig. 1. Vapor growth of perovskite film: (a) Schematic growth processes of two-step vapor growth of perovskite films; (b) reaction schematic between the PbI₂ structure and the MAI molecule; (c) the cross-sectional morphology of the as-prepared device. 钙钛矿薄膜的气相制备流程及效果　(a)两步钙钛矿薄膜气相制备流程示意图; (b)PbI₂与MAI气体反应示意图; (c)器件SEM截面图

Fig. 2. (a) The XRD patterns; (b) reaction time for fully conversion of PbI₂ to MAPbI₃ under different reaction temperature; (c) UV-vis spectra of perovskite films synthesized under different temperature. 不同反应温度下钙钛矿薄膜的表征　(a)薄膜的XRD图谱; (b)不同反应温度下PbI₂向MAPbI₃完全转化所需的时间; (c)薄膜的吸收图谱

Fig. 3. Reaction temperature effect on the morphology of perovskite film: (a)–(d) SEM images of perovskite films with reaction temperature of (a) 140 ℃, (b) 160 ℃, (c) 180 ℃ and (d) 200 ℃ (the scale bars in the SEM images are 1 ); (e) statistics of grain size under different reaction temperature; (f) as prepared MAPbI₃ film with area about 72 cm². 温度对钙钛矿薄膜形态的影响　(a)—(d)反应温度分别为140 ℃, 160 ℃, 180 ℃以及200 ℃时制备的钙钛矿的SEM形貌图(白色线段长度为1 ); (e)不同反应温度下的钙钛矿薄膜晶体粒径统计; (f)气相法制备面积约72 cm²的MAPbI₃薄膜

Fig. 4. Trap density measurement in perovskite synthesized under different temperature: (a) 140 ℃; (b) 160 ℃; (c) 180 ℃ and (d) 200 ℃.钙钛矿薄膜的缺陷密度测试　(a) 140 ℃; (b) 160 ℃; (c) 180 ℃; (d) 200 ℃

Fig. 5. Device performance of perovskite photovoltaic devices: (a) 0.045 cm² device reverse J-V curves under 1 Sun AM 1.5 G; (b) statistical distribution of PCE; reverse and forward J-V curves of devices (0.045 cm²) grown at (c) 180 ℃ and (d) 140 ℃; (e) reverse and forward J-V curves of device (1 cm²) grown at 180 ℃ and (f) corresponding optical image. 钙钛矿光伏器件性能　(a)标准光照下面积为0.045 cm²器件的J-V曲线; (b)多组器件效率的统计结果; (c)面积为0.045 cm²器件180 ℃下制备的器件回滞曲线; (d)面积为0.045 cm²器件140 ℃下制备的器件回滞曲线; (e)面积为1 cm² 器件180 ℃下制备的器件J-V曲线; (f) 1 cm² 器件的光学图片