添加不同配體之二硫化鐵奈米晶體對有機-無機鈣鈦礦太陽能電池之影響

Abstract

有機-無機鈣鈦礦太陽能電池由於具有高吸收及高轉換效率，是目前太陽能電池中備受矚目的材料之一。而本篇研究所使用的元件結構FTO/TiO2/CH3NH3PbI3-xClx /spiro-OMeTAD / Au所製成的平面異質介面結構鈣鈦礦太陽能電池。由於此種太陽能電池容易受到鈣鈦礦層的形貌而影響效率，因此許多研究嘗試調控鈣鈦礦層的表面形貌藉此改善效率。而本次實驗利用合成出顆粒大小約15奈米的二硫化鐵奈米晶體，以不同配體置換後，配置成不同的濃度，再以相同比例加入鈣鈦礦的前驅溶液中製成元件，可以發現元件的短路電流提升，但開路電壓則明顯下降，因此對元件做各種的分析，例如掃描式電子顯微鏡(SEM)、X光繞射光譜(XRD)、可見光吸收光譜(Visible Absorption Spectroscopy)、外部量子效率(EQE)，可以發現到添加二硫化鐵奈米晶體的元件確實影響到鈣鈦礦層的形貌，進而影響到鈣鈦礦太陽能電池元件的表現。Inorganic-organic perovskite solar cells are one of the most significant materials because of its high absorption and power conversion effiency. In this study, the architecture of our planar heterojunction perovskite solar cells is FTO / TiO2 / CH3NH3PbI3-xClx / spiro-OMeTAD / Au. Because this type of solar cell is easily affected by the morphology of perovskite layer, many studies tried to control the morphology of it to improve the effiency. In our work, we synthesized pyrite iron(II) sulfide nanocrystals (FeS2 NCs) with respectively different ligands acting as additive. Each FeS2-ligand with different concentrations is added separately into perovskite precursor solution. Compared with the pristine device, the FeS2-added one shows obviously higher Short circuit current (Jsc) and lower Open circuit voltage (Voc). The as-prepared cells were analyzed in various techniques, including SEM, XRD, Visible Absorption Spectroscopy and EQE, and show significant morphological change in perovskite layer, which dominates the cell’s efficiency.