Single step hydrothermal synthesis of mixed valent V6O13 nano-architectures: A case study of the possible applications in electrochemical energy conversion

Availability of several stable vanadium oxidation states offers numerous advantages in terms of applications but at the same time it poses great challenge to isolate them in single phase during their synthesis process. In this study, we developed a facile single step hydrothermal synthesis of V6O13 nanoarchitectures using environmental friendly citric acid as a reducing agent. By means of time dependant hydrothermal conditions study, we observed evolution of several stable vanadium oxide phases. The as-synthesized powder samples phase confirmation was thoroughly studied by powder X-ray diffraction and transmission electron microscopy. The morphology of the products formed was investigated at each hydrothermal reaction time. Finally, these V6O13 nano-architectures were employed as counter electrode (CE) in dye sensitized solar cells (DSSCs). The photovoltaic performance and the electrical impedance studies of the DSSC device made use of V6O13 nano-architectures are reported here. It is believed that with further optimization, this relatively inexpensive material can act as efficient CE for DSSCs, which thereby open up a new avenue for vanadium oxides as a new class of materials for clean energy generation. (C) 2017 Elsevier B. V. All rights reserved.