Economically viable V2O3@activated carbon composite materials as counter electrodes for dye sensitized solar cells by single step reduction

V 2 O 3 @activated carbon (V 2 O 3 @C) composite catalysts with different mass ratios have successfully been fabricated using a facile one-step the reduction of ammonium vanadate (NH 4 VO 3 ) with AC in a high-temperature solid-state reaction. V 2 O 3 @C composites were further served as catalytic materials for counter electrodes (CEs) in encapsulation of dye sensitized solar cells (DSSCs). The morphology and microstructure of each V 2 O 3 @C composite were determined by scanning electron microscopy and X-ray diffraction. Cyclic voltammetry studies revealed that the V 2 O 3 @C composites showed a higher electrocatalytic activity than AC and V 2 O 3 for the reduction of triiodide ions. Electrochemical impedance spectroscopy and Tafel analysis data for the symmetrical cells indicated a lower charge transfer resistance and higher exchange current density for V 2 O 3 @C composite than AC and V 2 O 3 . The experimental results showed that power conversion efficiencies (PCE) of 4.94, 5.55 and 5.32% were obtained for AC:NH 4 VO 3 mass ratios of 1:3, 2:3 and 4:3 as counter electrode toward the reduction of I 3 − /I − ions respectively, which were superior to higher than that of AC (2.10%) and V 2 O 3 (3.33%) electrode under the same conditions. The enhanced electrode performance can be ascribed to the combined effects of the relatively larger surface area and higher conductivity of V 2 O 3 @C composite catalysts.