posted on 2021-12-06, 17:35authored byLong Hu, Qingya Li, Yuchen Yao, Qiang Zeng, Zizhen Zhou, Claudio Cazorla, Tao Wan, Xinwei Guan, Jing-Kai Huang, Chun-Ho Lin, Mengyao Li, Soshan Cheong, Richard D. Tilley, Dewei Chu, Jianyu Yuan, Shujuan Huang, Tom Wu, Fangyang Liu
A cost-effective
and environmentally friendly Pb source is a prerequisite
for achieving large-scale, low-cost perovskite photovoltaic devices.
Currently, the commonly used method to prepare the lead source is
based on a fire smelting process, requiring a high temperature of
more than 1000 °C, which results in environmental pollution.
Spent car lead acid batteries are an environmentally hazardous waste;
however, they can alternatively serve as an abundant and inexpensive
Pb source. Due to “self-purification”, quantum dots
feature a high tolerance of impurities in the precursor since the
impurities tend to be expelled from the small crystalline cores during
colloidal nucleation. Herein, PbI2 recycled from spent
lead acid batteries via a facile low-temperature solution process
is used to synthesize CsPbI3 quantum dots, which simultaneously
brings multiple benefits including (1) avoiding pollution originating
from the fire smelting process; (2) recycling the Pb waste from batteries;
and (3) synthesizing high-quality quantum dots. The resulting CsPbI3 quantum dots have photophysical properties such as PLQY and
carrier lifetimes on par with those synthesized from the commercial
PbI2 due to expelling of the impurity Na atoms. The resulting
solar cells deliver comparable power conversion efficiencies: 14.0%
for the cells fabricated using recycled PbI2 and 14.7%
for the cells constructed using commercial PbI2. This work
paves a new and feasible path to applying recycled Pb sources in perovskite
photovoltaics.