title: Colloidal Precursor-Induced Growth of Ultra-Even CH3NH3PbI3for High-Performance Paintable Carbon-Based Perovskite Solar Cells.
abstract: Carbon-based hole transport material (HTM)-free perovskite solar cells (PSCs) have attracted intense attention due to their relatively high stability. However, their power conversion efficiency (PCE) is still low, especially for the simplest paintable carbon-based PSCs (C-PSCs), whose performance is greatly limited by poor contact at the perovskite/carbon interface. To enhance interface contact, it is important to fabricate an even-surface perovskite layer in a porous scaffold, which is not usually feasible due to roughness of the crystal precursor. Herein, colloidal engineering is applied to replace the traditional crystal precursor with a colloidal precursor, in which a small amount of dimethyl sulfoxide (DMSO) is added into the conventional PbI2dimethylformamide (DMF) solution. After deposition, PbI2(DMSO) adduct colloids (which are approximately tens of nanometers in size) are stabilized and dispersed in DMF to form a colloidal film. Compared with PbI2and PbI2(DMSO) adduct crystal precursors deposited from pure DMF and DMSO solvents, respectively, the PbI2(DMSO) adduct colloidal precursor is highly mobile and flexible, allowing an ultra-even surface to be obtained in a TiO2porous scaffold. Furthermore, this ultra-even surface is well-maintained after chemical conversion to CH3NH3PbI3in a CH3NH3I solution. As a result, the contact at the CH3NH3PbI3/carbon interface is significantly enhanced, which largely boosts the fill factor and PCE of C-PSCs. Impressively, the achieved champion PCE of 14.58% is among the highest reported for C-PSCs.
authors.affiliation: School of Materials Science and Engineering, Beihang University , No. 37 Xueyuan Road, Haidian District, Beijing 100191, People's Republic of China.
authors.forename: Xiaowen
authors.initials: X
authors.lastname: Chang
authors.affiliation: School of Materials Science and Engineering, Beihang University , No. 37 Xueyuan Road, Haidian District, Beijing 100191, People's Republic of China.
authors.forename: Weiping
authors.initials: W
authors.lastname: Li
authors.affiliation: School of Materials Science and Engineering, Beihang University , No. 37 Xueyuan Road, Haidian District, Beijing 100191, People's Republic of China.|Department of Chemistry, The Hong Kong University of Science and Technology , Clear Water Bay, Kowloon, Hong Kong.
authors.forename: Haining
authors.initials: H
authors.lastname: Chen
authors.affiliation: School of Materials Science and Engineering, Beihang University , No. 37 Xueyuan Road, Haidian District, Beijing 100191, People's Republic of China.
authors.forename: Liqun
authors.initials: L
authors.lastname: Zhu
authors.affiliation: School of Materials Science and Engineering, Beihang University , No. 37 Xueyuan Road, Haidian District, Beijing 100191, People's Republic of China.
authors.forename: Huicong
authors.initials: H
authors.lastname: Liu
authors.affiliation: School of Materials Science and Engineering, Beihang University , No. 37 Xueyuan Road, Haidian District, Beijing 100191, People's Republic of China.
authors.forename: Huifang
authors.initials: H
authors.lastname: Geng
authors.affiliation: School of Materials Science and Engineering, Beihang University , No. 37 Xueyuan Road, Haidian District, Beijing 100191, People's Republic of China.
authors.forename: Sisi
authors.initials: S
authors.lastname: Xiang
authors.affiliation: School of Materials Science and Engineering, Beihang University , No. 37 Xueyuan Road, Haidian District, Beijing 100191, People's Republic of China.
authors.forename: Jiaming
authors.initials: J
authors.lastname: Liu
authors.affiliation: Department of Chemistry, The Hong Kong University of Science and Technology , Clear Water Bay, Kowloon, Hong Kong.
authors.forename: Xiaoli
authors.initials: X
authors.lastname: Zheng
authors.affiliation: Department of Chemistry, The Hong Kong University of Science and Technology , Clear Water Bay, Kowloon, Hong Kong.
authors.forename: Yinglong
authors.initials: Y
authors.lastname: Yang
authors.affiliation: Department of Chemistry, The Hong Kong University of Science and Technology , Clear Water Bay, Kowloon, Hong Kong.
authors.forename: Shihe
authors.initials: S
authors.lastname: Yang
keywords: carbon-based perovskite solar cells; dimethyl sulfoxide; dimethylformamide; hole transport material-free; interface contact