Solar cells are a reliable technology for converting solar energy directly into electricity. How to improve the energy conversion efficiency of solar cells? Recently, Prof Yang Bin of our university has collaborated with Dr. Yi Liu and Dr. Bo He of the Lawrence Berkeley National Laboratory to develop a new type of technology. The ADA intermediate band gap non-fullerenes acceptor material IDTT-T was used in combination with a low bandgap PTB7-th polymer donor to produce a high performance organic solar cell. The energy loss of the battery was only 0.57 eV, open circuit voltage up to 1V, energy conversion efficiency of approximately 10%.
The research work is entitled "Molecular Engineering for Large Open-Circuit Voltage and Low Energy Loss in Around 10% Non-fullerene Organic Photovoltaics" published in the new journal of the American Chemical Society "ACS Energy Letters". An author and second correspondence author, Dr. Bo He and Dr. Yi Liu from the Lawrence Berkeley National Laboratory were the first author and the first author of the paper.
The acceptor material is the main component of the active layer of the organic solar cell. The non-fullerene acceptor material with a fused ring structure has excellent properties such as adjustable electron band, simple synthesis, and low manufacturing cost, and exhibits great development. Potential. At present, domestic and foreign researchers are devoted to designing and developing narrow-bandgap non-fullerenes acceptor materials with good photoelectric response performance. However, the types of highly efficient wide bandgap organic donor materials that match them are very limited, and the narrow band The LUMO energy level of the gap acceptor material is low, which is not conducive to the increase of the open circuit voltage of the solar cell.
Professor Yang Bin et al. used the weak electron-withdrawing group diethyl thiobarbituric acid instead of the strong electron-withdrawing group cyanoanthrone to obtain a new type of ADA with a higher LUMO level than the conventional non-fullerene acceptor material ITIC. A mid-band gap non-fullerene acceptor material, IDTT-T, was used in combination with a low-bandgap PTB7-th polymer donor to produce a high performance organic solar cell. This work shows that by using intermediate New design ideas for combination of band gap non-fullerene acceptor materials and narrow bandgap donor materials can achieve high open-circuit voltage and high energy conversion efficiency of organic solar cells at the same time.
