Novel triphenylamine-based copolymers for all-polymer solar cells

Abstract Constructing non-planar conjugated systems is important to achieve high performing acceptors for non-fullerene solar cells. Non-planar unit triphenylamine ( TPA ) was copolymerized with accepting units, isoindigo ( IIG ) or naphthalene diimide ( NDI ), to afford three non-planar conjugated polymers. By changing the accepting moieties and the alkyl chains, the physicochemical properties and photovoltaic characteristics of the conjugated polymers were systematically tuned. As a result, the efficiency of the all-polymer solar cells was significantly enhanced to 2.2%.