[18a-PB01-1~25] 12.5 Organic and hybrid solar cells

▲ [18a-PB01-11] 2-Chloroethyl Vinyl Ether Chain-Grafted Carbazole Derivatives Interlayer
Enhances Power Conversion Efficeincy of Perovskite Solar Cells

〇(D)YuanYu Chiu¹, Ming-Chung Wu^1,2, KaiChi Hsiao¹, ShihHsuan Chen¹, ChingMei Ho¹ (1.Chang Gung Univ, 2.Chang Gung Memorial Hospital at Linkou)

Keywords:perovskite, solar cell, Carbazole

Perovskite solar cells (PSCs), a promising next-generation thin-film photovoltaic, have attracted great attention in recent decades. Its photoelectric conversion efficiency (PCE) increased significantly from 3.8% to 25.7%. A mixed cation of formamidinium-based perovskite is widely used as a light-absorbed layer in high-efficiency PSCs. With regard to promote the PCE of PSCs, carrier transfer between a perovskite layer and carrier extraction layers is feasible to reach the target. Herein, 2-chloroethyl binyl ether grafted carbazole (CVE-carbazole), exhibiting an electron-donating group, is synthesized to serve as an interlayer between the perovskite layer and the hole transport layer (HTL). By modifying the side chain of carbazole, the hydrophobicity of carbazole derivative can be manipulated, and the effect of modified side chains can also tune its energy level. With high electron density on the main chain, CVE-carbazole exhibits good hole extraction ability. Time-resolved photoluminescence (TRPL) spectroscopy revealed that the CVE-carbazole interlayer can efficiently extract charged carriers, and thereby facilitates electron and hole separation. Based on the hydrophobicity and appropriate energy level of CVE-carbazole, the PSC with CVE-carbazole interlayer can achieve a PCE of 21.2% compared with a PCE of 19.7% from the PSC without the interlayer. The CVE-carbazole interlayer confers PSCs to obtain highly efficient perovskite solar cells.