Interfacial Engineering in Functional Materials for Dye-Sensitized Solar Cells

8 Binary Semiconductor Metal Oxide as Photoanodes

S.S. Kanmani¹, I. John Peter², A. Muthu Kumar², P. Nithiananthi², C. Raja Mohan², and K. Ramachandran²

¹ Dr. N.G.P. Arts and Science College, Coimbatore, Tamilnadu, India

² Nanostructure Lab, Department of Physics, The Gandhigram Rural Institute‐Deemed to be University, Gandhigram, Tamilnadu, India

8.1 Why Metal Oxide Semiconductors?

As both natural and synthetic metal oxide semiconductors (MOSs) have diverse applications and the properties of MOS can be tailored in many ways, viz., varied choice of morphologies, introducing oxygen vacancies, doping. In photovoltaics, MOSs serve as a scaffold layer for loading dyes in dye‐sensitized solar cells (DSSCs) and organic–inorganic hybrid perovskites in perovskite solar cells (PSCs), as well as electron and hole transport layers in DSSCs and organic solar cells (OSCs). The function of scaffold in DSSCs is to facilitate charge separation and charge transport, whereas that of the transport layers is to conduct one type of charge carrier block to the other type. Therefore, tailoring their properties is inevitable to develop high‐performing photovoltaic devices using them. On the other hand, the electrochemical properties of the MOS such as band edge energies determine their success as photocatalysts [1].

The wide‐band‐gap MOSs (e.g. >3 eV) having suitable band position relative to dye (or photosensitizer) have been used for the fabrication of DSSCs. Owing to the wide band ...