Enhanced Electrical Property of Compact TiO₂ Layer via Platinum Doping for High‐Performance Perovskite Solar Cells

Abstract

The electron-transporting layer (ETL) plays a critical role in improving the charge extraction and suppressing the carrier recombination in planar perovskite solar cells (PSCs). Compact titanium dioxide (TiO 2 ) film is a widely used as an ETL in conventional n-i-p PSCs. However, there is still much room for improvement in the electron mobility and reducing the oxygen vacancies of the compact TiO 2 film. Herein, Pt-doped TiO 2 film with outstanding electron-transporting property and complete coverage on the substrates is reported by the authors. Pt-doping results in a tailed band level of TiO 2 , which could suppress the charge accumulation at the interface of TiO 2 -Pt/perovskite. Consequently, TiO 2 -Pt ETL based PSCs deliver a power conversion efficiency as high as 20.05% with an open-circuit voltage of 1.15 V, a fill factor of 0.75, a short-circuit current density of 23.83 mA cm À2 and remarkably alleviated hysteresis behavior.

Carbon‐Electrode Based Perovskite Solar Cells: Effect of Bulk Engineering and Interface Engineering on the Power Conversion Properties

“…It should be noted that there exists a large amount of efficient bulk/interface engineering strategies . These progresses are worthy to be carefully studied.…”

In-situ formed and low-temperature deposited Nb: TiO2 compact-mesoporous layer for hysteresis-less perovskite solar cells with high performance

“…In particular, a wide range of elements have been chosen to prepare TiO 2 doping layers in PSCs, including Indium (Li) [22][23] , Niobium (Nb) [24][25] , Platinum (Pt) [26] , Neodymium (Nd) [27] , and Aluminum (Al) [28] . Among these elements, Niobium metal (Nb) is a good candidate as a doping material for titanium oxide electron transport materials due to its similar radius (70 pm) with that of titanium (68 pm).…”

In-situ formed and low-temperature deposited Nb: TiO2 compact-mesoporous layer for hysteresis-less perovskite solar cells with high performance

“…Extensive efforts have been made to develop high-quality TiO 2 electron transport layers (ETLs) with high electron mobility, such as through morphology optimization, surface modi cations, and doping. In particular, a wide range of elements have been chosen to prepare TiO 2 doping layers in PSCs, including Indium (Li) [25][26] , Niobium (Nb) [27][28] , Platinum (Pt) [29] , Sodium (Na) [30] , Neodymium (Nd) [31] , and Aluminum (Al) [32] . For instance, it is reported that the Li-doped TiO 2 is bene cial to the performance of the mesoporous-structure PSCs, especially the hysteresis effect [26] .…”

“…For instance, it is reported that the Li-doped TiO 2 is bene cial to the performance of the mesoporous-structure PSCs, especially the hysteresis effect [26] . Liao et al reported a Pt-doped TiO 2 ETL which was demonstrated to improve the charge carrier extraction and injection e ciency in n-i-p PSCs [29] . Other ions such as Na, Nb and transition metal ions [30][31][33][34][35] were used to modify surface or passivate defect of TiO 2 , contributing to less non-radiative recombination.…”