Design of efficient photocatalysts through band gap engineering

Designing an efficient catalyst for reactions that might solve the energy crisis is the need of the hour. Generating hydrogen by splitting of water and reduction of carbon dioxide are two important reactions which can be carried out using semiconductor catalysts in the presence of sunlight. Efficiency of these reactions depends largely on the catalytic properties of the photocatalyst. The desired catalytic activity can be achieved by altering the band structure of the semiconductor photocatalyst. Herein we discuss various aspects of band engineering of the photocatalysts. Engineering the band structure to reduce the band gap and altering the positions of band edges are ways by which desired catalytic activities can be achieved.