Innovative approach to perovskite solar cells achieves 24.5% efficiency

Innovative approach to perovskite solar cells achieves 24.5% efficiency

by Simon Mansfield

Sydney, Australia (SPX) Mar 28, 2024

In groundbreaking research published in Nano Energy, a team led by Prof. CHEN Chong at the Hefei Institutes of Physical Science, part of the Chinese Academy of Sciences, has significantly improved the performance of perovskite solar cells (PSCs). By integrating inorganic nano-material tin sulfoxide (SnSO) as a dopant, they have boosted the photoelectric conversion efficiency (PCE) of PSCs to an impressive 24.5%.

Traditional methods of enhancing the charge transport in the critical hole transport layer (HTL) of PSCs involve the use of lithium trifluoromethanesulfonyl imide (Li-TFSI) to facilitate the oxidation of the HTL material spiro-OMeTAD. However, this method suffers from low doping efficiency and can leave excess Li-TFSI in the spiro-OMeTAD film, reducing its compactness and long-term conductivity. Additionally, the oxidation process typically requires 10-24 hours to achieve the desired electrical conductivity and work function.

The HFIPS team’s innovation lies in their development of a rapid and replicable method to control the oxidation of nanomaterials, using SnSO nanomaterial to pre-oxidize spiro-OMeTAD in precursor solutions. This novel approach not only enhances conductivity but also optimizes the energy level position of the HTL, culminating in a high PCE of 24.5%.

One of the key advantages of the SnSO-regulated spiro-OMeTAD HTL is its pinhole-free, uniform, and smooth morphology, which maintains its performance and physical integrity even under challenging conditions of high temperature and humidity. Additionally, the oxidation process facilitated by this method is significantly faster, taking only a few hours- a crucial factor in improving the commercial production efficiency of PSCs.

Prof. CHEN Chong highlighted the importance of this breakthrough, stating, “Also, the oxidation process only takes a few hours, which is good for improving the commercial preparation efficiency of PSCs.” This advancement not only marks a significant leap in the efficiency and stability of PSCs but also holds substantial implications for their commercial viability.

Research Report:A nanomaterial-regulated oxidation of hole transporting layer for highly stable and efficient perovskite solar cells