Charge recombination and dark current are two main negative processes in dye-sensitized solar cells (DSSCs). Herein, a new 3D triphenylamine electron donor group was developed to resist charge recombination and dark current in triphenylamine-sensitized solar cells. The new donor group has coplanar triphenylamine moiety, and therefore it outperforms the conventional triphenylamine moiety for higher electron donor ability, as evidenced by UV vis spectroscopic analysis. Furthermore, its 3D structure can help resist dark current and restrain charge recombination, as demonstrated by dark current and electrochemical impedance spectroscopic (EIS) studies. The sensitizer NUISTI including the 3D novel donor group achieves a 21.1% higher energy conversion efficiency than conventional triphenylamine .(C) 2017 Elsevier Ltd. All rights reserved.