银纳米相吸收增强型钙钛矿太阳电池薄膜的制备及性能研究

Properties of Silver Nanostructures Incorporated Perovskite Based Thin Films for Solar Cell Applications

分别将银纳米相溶胶(银纳米颗粒、Ag@SiO_2核壳结构、银纳米线)掺入氧化铝异丙醇溶液中制成具有蜂窝结构的介孔层材料,然后在介孔层表面制备CH_3NH_3Pb I3钙钛矿吸收层得到Al_2O_3/CH_3NH_3Pb I3复合薄膜,并对复合膜的微观结构、光吸收特性及太阳电池器件性能进行了测试和分析。研究表明,Al_2O_3/CH_3NH_3Pb I3复合膜与CH_3NH_3Pb I3在可见光区域吸收光谱基本相同,含量极少的Al_2O_3对CH_3NH_3Pb I3吸光性能影响较小。而掺入银纳米相可明显改善CH_3NH_3Pb I3钙钛矿薄膜的吸收性能。当银纳米颗粒、Ag@SiO_2核壳结构和银纳米线相对浓度比分别为0.15、0.3及0.15时,CH_3NH_3Pb I3吸光性能分别达到最佳;银纳米相浓度继续增大时,薄膜的光吸收性能逐渐减弱。此外,掺入Ag@SiO_2核壳结构可使钙钛矿薄膜太阳电池光电转换效率由6.28%增大到7.09%,而银纳米颗粒和银纳米线由于会增大太阳电池内部载流子传输路径,提高电子空穴对复合效率,最终反而降低了太阳电池短路电流密度和光电转换效率。

Silver nanostructures （Ag nanoparticles, Ag@SiO2 core-shell nanoparticles ＆ Ag nanowires） were firstly added into aluminum oxide isopropanol solution to form cellular Al2O3 mesoporous layers for perovskite solar cell applications, respectively. Then CH3NH3PbI3 organic-inorganic hybrid perovskites were fabricated and attached to this matrix. Absorption spectra of AI203/CH3NH3PbI3 composite and CH3NH3PbI3 were found to be basically the same in the visible region, indicating that Al2O3 had less impact on the absorption performance of CHaNH3PbI3. However, the incorporation of silver nanostructures could significantly improve the absorption properties of the perovskites, and the best performance could be achieved with the concentration ratios of Ag nanoparticles, Ag@SiO2 core-shell nanoparticles and Ag nanowires of 0.15, 0.3 and 0.15, respectively. Further increasing the concentration of silver incorporation would probably cause halogenation and reduce the absorption properties of CH3NHaPbI3. In addition, the efficiency of perovskite solar cell could be improved from original 6.28% to 7.09% after addition of Ag@SiO2 core-shell nanoparti- cles. In contrast, the incorporation of Ag nanoparticles ＆ nanowires tended to reduce the short circuit current density and conversion efficiency of the fabricated solar ceils, because they could prolong the internal carrier transport path and hence increase the recombination probability of the electron-hole pairs.