Facile Interfacial Engineering of Mesoporous TiO2 for Low-Temperature Processed Perovskite Solar Cells.

Jiyoon Nam,Eun-Jin Song,Chang Su Kim,Jongbok Kim,Sungjin Jo,Jung-Dae Kwon,Inje Nam

doi:10.3390/nano9091220

Abstract

The mesoporous TiO2 nanoparticle-based scaffold structure is the best electron transport layer (ETL) for perovskite solar cells (PSCs) and is still used in most PSCs with optimal photovoltaic characteristics. However, the high sintering temperature of TiO2 nanoparticles required to remove binders from the TiO2 paste limits PSC application to flexible electronics. In this study, a simple interface modification process involving ethanol rinsing is developed to enhance the photovoltaic characteristics of low-temperature processed PSCs. This easy and fast technique could enable remarkable performance by PSCs by significantly increasing the fill factor and current density, leading to a power conversion efficiency more than four times that of untreated solar cells.

Highlights

Hybrid metal–halide perovskite solar cells (PSCs) have attracted considerable attention because of their low cost, high efficiency, and ease of fabrication
We developed a novel simple surface modification process that involves ethanol rinsing at the end of the mesoporous TiO2 nanoparticles annealing; this SMP enhanced the power conversion efficiency (PCE) of the LT-PSCs more than four times compared with untreated PSCs
Residual binders resulting from the insufficient sintering temperature of mesoporous TiO2 paste are generally considered the reason for the degradation of the photovoltaic characteristics of PSCs [25] and, if they directly affect the solar cell properties, the crystallinity of the light-absorbing layer on TiO2 electron transport layer (ETL) could be potentially altered

Summary

Introduction

Hybrid metal–halide perovskite solar cells (PSCs) have attracted considerable attention because of their low cost, high efficiency, and ease of fabrication. Conventional PSC fabrication methods, based on a solution process, are suitable for flexible polymer substrates [6,7]. The high-temperature sintering process that is required to remove organic binders and solvents from the TiO2 paste used for the fabrication of the mesoporous TiO2 electron transport layer (ETL) is not feasible for flexible polymer substrates. This high-temperature process limits the variety of substrates and the mass production scalability. To overcome these limitations, novel low-temperature processes and alternative materials for TiO2 ETL fabrication have been investigated

Methods

Results

Conclusion