Led by Prof. Li Gang, Chair Professor of Energy Conversion Technology and Sir Sze-Yuen Chung Endowed Professor in Renewable Energy, a PolyU research team has achieved a breakthrough power-conversion efficiency (PCE) of 19.31% with organic solar cells (OSCs), also known as polymer solar cells. This remarkable binary OSC efficiency will help enhance the application of these advanced solar energy devices.

The PCE, a measure of the power generated from a given solar irradiation, is considered a significant benchmark for the performance of photovoltaics, or solar panels, in power generation. The improved efficiency of over 19% that has been achieved by PolyU constitutes a record for binary OSCs, which have one donor and one acceptor in the photo-active layer.

The research team invented a novel OSC morphology-regulating technique by using 1,3,5-trichlorobenzene as a crystallisation regulator. This new technique boosts OSC efficiency and stability.

The findings are described in the study “19.3% Binary Organic Solar Cell and Low Non-Radiative Recombination Enabled by Non-Monotonic Intermediate State Transition” published in Nature Communications.