In this study two donor-acceptor type alternating polymers containing electron-deficient benzotriazole moiety and electron-rich selenophene bearing benzodithiophene moiety; P1 and P2, were designed and synthesized via Stille polymerization. Moreover, the effects of thiophene and selenophene as pi-bridges on optical, electrochemical and optoelectronic features of polymers were examined. The optical band gap values of P1 and P2 were found as 1.47 eV and 1.72 eV, respectively. Cyclic voltammetry studies were performed to investigate the electrochemical properties of polymers. The HOMO and LUMO energy levels of P1 and P2 were recorded as -5.45/-3.09 eV and -5.49/-3.21 eV, correspondingly. Optical, electrochemical and optoelectronic studies of P1 and P2 demonstrated that both two polymers were suitable to be utilized as donor materials for bulk heterojunction organic solar cell applications. Photovoltaic properties were investigated ITO/PEDOT:PSS/Polymer:PC71BM/LiF/Al device structure measured under standard AM 1.5 G illumination (100 mW/cm(2)). As a consequence of photovoltaic measurements, the highest power conversion efficiency values were recorded as 2.41% for P1:PC71BM (1:2) (w/w) based device with a V-OC 0.83 V, a J(SC) 5.66 mA/cm(2), and fill factor of 51.22% values. (c) 2020 Elsevier B.V. All rights reserved.