Computational chemistry

Chemistry

Materials science

Programming language

Optoelectronics

Biochemistry

Electronic structure

Physics

Heterojunction

Valence band

Electron

Nanotechnology

Ternary operation

Catalysis

Quantum mechanics

Charge carrier

Computer science

Photocatalysis

Density functional theory

Band gap

Semiconductor

Conduction band

Chemistry - A European Journal

Electronic structure calculations provide a useful complement to experimental characterization tools in the atomic‐scale design of semiconductor heterojunctions for photocatalysis. The band alignment of the heterojunction is of fundamental importance to achieve an efficient charge carrier separation, so as to reduce electron/hole recombination and improve photoactivity. The accurate prediction of the offsets of valence and conduction bands in the constituent units is thus of key importance but poses several methodological and practical problems. In this Minireview we address some of these problems by considering selected examples of binary and ternary semiconductor heterojunctions and how these are determined at the level of density functional theory (DFT). The atomically precise description of the interface, the consequent charge polarization, the role of quantum confinement, the possibility to use facet engineering to determine a specific band alignment, are among the effects discussed, with particular attention to pros and cons of each one of these aspects. This analysis shows the increasingly important role of accurate electronic structure calculations to drive the design and the preparation of new interfaces with desired properties.

Rational Design of Semiconductor Heterojunctions for Photocatalysis