Researchers at the Hong Kong Polytechnic University (PolyU) have achieved an impressive power conversion efficiency (PCE) of 19.31% using organic solar cells (OSC), also known as polymer solar cells. The exceptional performance of this dual OSC will help improve these advanced solar device applications.
PCE (Power Conversion Efficiency), which is a measure of the energy obtained from a given amount of solar radiation, is an important measure of the efficiency of photovoltaic cells (PV) or solar panels in producing electricity. The over 19% efficiency achieved by the Polytechnic University researchers is a record for bilateral OSCs with donors and acceptors in the photovoltaic layer.
Professor of Energy Transformation Technologies Chair LA A research team led by Zhang and Sir Sze-Yen Chung, Professor of Renewable Energy at the University of Beaulieu, developed a new technique to control OSC morphology using 1,3,5-trichlorobenzene as a crystal. This new control technology improves OSC performance and stability.
The team developed a non-monotonic intermediate state manipulation (ISM) technique to manipulate OSC heterogeneous (BHJ) morphology while improving crystallization dynamics and energy loss in non-fullerene OSCs. In contrast to traditional solvent addition methods, which rely on excessive aggregation of molecules in the membrane, the ISM technique promotes more orderly molecular stacking and the formation of favorable molecular aggregates. This greatly increases PCE and reduces unwanted non-radiative recombination loss. In particular, non-radiative recombination reduces the efficiency of light generation and increases heat loss.
The research team's findings are described in a study titled "19.3% binary organic solar cells with non-intermediate transition state and low non-radiative recombination properties" published in Nature Communications. Converting solar energy into electricity is an important technology for a sustainable environment. Although OSC is a promising device that harnesses solar energy at a low cost, its performance needs to be improved if it is to be widely used in practice.
Organic solar cells that do not depend on fullerene acceptors are the focus of research in organic photovoltaics due to innovations in material handling and morphology. However, the focus of cell biological research is to emphasize non-radiative recombination loss and improve efficiency.
"The research challenge arose from the morphological control method of the additive-based standard, which suffers non-radiative recombination losses, thus reducing the open-circuit voltage due to increased coupling," said Professor Li. The research team spent nearly two years developing a non-monotonic ISM technique to improve OSC performance and reduce non-radiative recombination losses. Publication of the studies holds promise for expanding OSC research.
"This new discovery will make OSC research an exciting field and is likely to create huge opportunities for applications such as wearable electronics and integrated photovoltaic construction," said Professor Li. More than 20%, with more stable performance and other unique advantages such as flexibility, transparency, stretchability, light weight, and customizable colors.
Professor Lee has been recognized as a Distinguished Scholar for nine consecutive years since 2014, highlighting his significant impact on global research. Since 2005, his pioneering contributions to polymer solar cell research have had a lasting impact on the development of printable solar power and have been recognized worldwide.
Based on research in the field of OPV, Professor LI's paper "High Efficiency Solutions for Addressable Polymer Photovoltaic Cells by Polymer Blend Self-assembly" was published in Nature Materials in 2005. This is the first generation of OPV research advancing advanced solar technology. from this frontier study.
In 2010, Professor LI's paper "Towards a Brighter Future - 7.4% Energy Conversion Efficiency of Energy Efficient Monolithic Solar Cells" was published in Advanced Materials .
"Recent studies have shown a record low non-radiative recombination loss of 0.168 eV in binary OSCs with a PCE of over 19%," says Professor Li. We've been using it for two decades. We have developed advanced OSC capabilities and this will continue to accelerate the expansion of solar energy."
References: Naturals 4, 864-868 (2005). Highly efficient, solution-curable polymeric photocells by self-assembly of the polymer mixture. Advanced Materials Volume 22, Number 20 (2010). For a bright future: 7.4% efficiency heterogeneous polymer solar cells.
