李永玺博士后在Energy & Environment Science上发表题为"Non-fullerene polymer solar cells based on a selenophene-containing fused-ring acceptor with photovoltaic performance of 8.6%"的论文，该论文被选为当期的封面论文。
In this work, we present a non-fullereneelectron acceptor bearing a fused five-heterocyclic ring containing seleniumatoms, denoted as IDSe-T-IC, for fullerene-free polymer solar cells (PSCs).This molecule exhibits a low band gap (Eg = 1.52 eV), strong absorption in the 600–850 nm region and a high LUMO level (_3.79 eV). When a large band gappolymer J51 (Eg = 1.91 eV) was used as the donor, complementary absorption ofthe polymer donor and acceptor was obtained in the wavelength range of 350–850nm. The solar cell based on J51:IDSe-T-IC gives a maximum PCE of 8.6%, with ahigh Voc of 0.91 V, a Jsc of 15.20 mA cm_2 and a fill factor (FF) of 62.0%.Moreover, this performance is much higher than that of J51:PC71BM based PSCsunder similar device fabrication conditions (PCE = 6.0%). The trade-off featuresof the Jsc and Voc existing in PSCs with fullerene acceptors have beenminimized in the fullerenefree PSCs based on IDSe-T-IC and J51. The resultsdemonstrate that fine-tuning the absorption and electronic energy levels ofnon-fullerene acceptors, and properly selecting a polymer donor to achievecomplementary absorption, is a promising way to further improve the performanceof the PSCs.