Open AccessGraphite/Carbon Black Counter Electrode Deposition Methods to Improve the Efficiency and Stability of Hole-Transport-Layer-Free Perovskite Solar Cells
Author(s) -
Muna Fathiah Don,
Piyasiri Ekanayake,
James R. Jennings,
Hideki Nakajima,
Chee Ming Lim
Publication year - 2022
Publication title -
acs omega
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.779
H-Index - 40
ISSN - 2470-1343
DOI - 10.1021/acsomega.2c02555
Subject(s) - materials science , perovskite (structure) , carbon black , electrode , chemical engineering , auxiliary electrode , graphite , energy conversion efficiency , tin oxide , layer (electronics) , nanotechnology , doping , optoelectronics , chemistry , composite material , electrolyte , natural rubber , engineering
The interfacial compatibility between the graphite/carbon black composite counter electrode (Gr/CB CE) and the perovskite layer is a crucial determinant of the performance of the hole-transport-layer-free carbon-based perovskite solar cells, and judicious selection of the Gr/CB CE application method is essential for achieving an optimum contact. In this work, three different types of Gr/CB CEs application methods are investigated: (1) deposition of Gr/CB on the fluorine-doped tin oxide (FTO) substrate, followed by clamping to the perovskite layer, (2) direct deposition of Gr/CB onto the perovskite layer, and (3) deposition of Gr/CB onto the PbI 2 precursor layer, followed by immersion in methylammonium iodide solution for the in situ conversion of PbI 2 to perovskite. The results revealed that Method 3 produced superior Gr/CB-perovskite contacts, resulting in up to 8.81% power conversion efficiency. The devices prepared using Method 3 also exhibited the best stability in the air, retaining 71.1% of their original efficiency after 1600 h of continuous testing. These results demonstrate that Gr/CB CEs can be considered excellent alternatives to the costly noble metals often employed in perovskite solar cells (PSCs) when deposited using a suitable technique.