Hole transport layer free stable perovskite solar cell with low temperature processed carbon electrodes

Perovskite solar cells, despite showing promising efficiency of more than 22%, is still far from realizing its full prospect on commercial scale, majorly owing to the cost associated with gold or silver counter electrode as well as hole transport material. Herein we report, low temperature processed carbon paste for hole transport layer free perovskite solar cell (PSC) fabricated in ambient conditions. Conductive (11.46 Ω □
^-1
) and adherent carbon paste were prepared with acrylic and ethyl cellulose based binders. We have optimized the amount of binder required for good adherence as well as conductivity. Perovskite solar cell with the FTO/TiO
₂
compact layer/TiO
₂
mesoporous layer/MAPbI
₃
/carbon architecture was fabricated with 7.41% power conversion efficiency. The prepared devices show promising stability for more than 500 hours.