Fused Benzotriazole A-Unit Constructs a D-π-A Polymer Donor for Efficient Organic Photovoltaics.

Herein, we originally developed a fused ring building block as an acceptor unit, namely, 2,6,10-trihydro-carbazole[3,4-:5,6-]bis[1,2,5]-triazole (CTA), through fusing two benzotriazoles (BTA) with a pyrrole ring. A p-type polymer PE93 containing the CTA unit exhibits relatively high molecular energy levels and excellent luminescent properties. The PE93:BTA76-based solar cell obtained a device efficiency of 12.

Recent Advances in Organic Photovoltaic Materials Based on Thiazole-Containing Heterocycles.

Organic solar cells (OSCs) have achieved great progress, driven by the rapid development of wide bandgap electron donors and narrow bandgap non-fullerene acceptors (NFAs). Among a large number of electron-accepting (A) building blocks, thiazole (Tz) and its derived fused heterocycles have been widely used to construct photovoltaic materials, especially conjugated polymers. Benefiting from the electron deficiency, rigidity, high planarity, and enhanced intra/intermolecular interactions of Tz-containing heterocycles, some related photovoltaic materials exhibit proper energy levels, optimized molecular aggregation, and active layer morphology, leading to excellent photovoltaic performance.

Carboxylate-Containing Wide-Bandgap Polymers for High-Voltage Non-Fullerene Organic Solar Cells.

As one of the polymer modification strategies, carboxylate functionalization has proved effective in downshifting the energy levels and enhancing polymer crystallinity and aggregation. However, high-performance carboxylate-containing polymers are still limited for organic solar cells (OSCs), especially with open-circuit voltage () above 1.0 V.