Perovskite Solar Cells Yielding Reproducible Photovoltage of 1.20 V.

Essa A Alharbi,Neha Arora,Pankaj Yadav,Michael Grätzel,M Ibrahim Dar,Ahmed Alyamani,Shaik M Zakeeruddin,Mohammad Hayal Alotaibi,Wolfgang Tress,Yahya A Alzhrani,Abdulrahman Albadri

doi:10.34133/2019/8474698

Abstract

High photovoltages and power conversion efficiencies of perovskite solar cells (PSCs) can be realized by controlling the undesired nonradiative charge carrier recombination. Here, we introduce a judicious amount of guanidinium iodide into mixed-cation and mixed-halide perovskite films to suppress the parasitic charge carrier recombination, which enabled the fabrication of >20% efficient and operationally stable PSCs yielding reproducible photovoltage as high as 1.20 V. By introducing guanidinium iodide into the perovskite precursor solution, the bandgap of the resulting absorber material changed minimally; however, the nonradiative recombination diminished considerably as revealed by time-resolved photoluminescence and electroluminescence studies. Furthermore, using capacitance-frequency measurements, we were able to correlate the hysteresis features exhibited by the PSCs with interfacial charge accumulation. This study opens up a path to realize new record efficiencies for PSCs based on guanidinium iodide doped perovskite films.

Highlights

Over the past few years, perovskite solar cells (PSCs) have attracted great attention in the applied and theoretical research fields [1]
Based on the photovoltaic characterization, we found that the incorporation of 5% guanidinium iodide (GuaI) into mixed-cation and mixedhalide perovskite films improved the overall performance of PSCs
We investigated the effect of guanidinium iodide incorporation into mixed-cation and mixed-halides perovskite films

Summary

Introduction

Over the past few years, perovskite solar cells (PSCs) have attracted great attention in the applied and theoretical research fields [1]. Since PSCs were first introduced by the Miyasaka group in 2009, the power conversion efficiency (PCE) has been improved from 3.8% to over 23% using solution-based deposition methods [2, 7]. These methods can generate films exhibiting pinholes and defects, which are detrimental to the device performance due to the occurrence of parasitic charge carrier recombination under operational conditions [8, 9]. To develop high-efficiency PSCs using solution-based approaches, one of the challenges is to achieve a rational control over the quality of the absorber layer [10, 11]. The role of grain boundaries acting as recombination centers is under debate as such processes depend on the processing conditions and composition of the perovskite layer [16,17,18,19,20]

Objectives

Methods

Results

Conclusion