Electrochemical interfacial charge transfer dynamics and photovoltaic performances of nanofibrous vanadium derivatives based platinum free counter electrodes in dye sensitized solar cells

摘要

This report compares the photovoltaic performance of vanadium based oxide (V_2O_3), nitride (VN) and carbide (VC) nanofibers (NFs) derivatives based counter electrodes (CEs) for dye sensitized solar cells (DSSC) obtained by low-cost, simple one step chemical method. The electrochemical behavior revealed that the charge transfer resistance (R_(ct)) of the VC-NFs counter electrode (CE) was 1.36 Ω cm~2, much lower than that of the Pt electrode (21.3 Ω cm~2). Such a low value of R_(ct) indicated that the VC-NFs exhibited higher catalytic activity than the traditional Pt based CE. The results revealed that the VC-NFs based DSSC shows comparable power-conversion efficiency (PCE) (η = 7.7%) to Pt (8.5%), while the η of VN-NFs and V_2O_3-NFs based DSSC are 6.8% and 5.0%, respectively.