Selective intercalation and diffusion processes in crystalline carbon nitride nanostructures

Graphitic carbon nitrides (gCN) are a family of low dimensional layered compounds based on alternating sp2-bonded C and N atoms; they can be exfoliated into few atomic layer thick nanostructures analogue to graphene, but with the additional benefit of chemical functionality derived from the heteroaromatic chemistry that allows tunable band gap, intercalation chemistry and applications in critical areas of catalysis and energy.
The goal of this project is to develop and apply accurate electronic structure computational techniques to study the structural chemistry of the carbon nitride materials, and how it correlates with desired properties, including:
- surface termination and control of the acid/base features of the N atoms exposed;
- band gap tuneability through intercalation chemistry and control of the photocatalytic properties;
- mechanism for intercalation and diffusion of guest atoms/ions/molecules in the carbon nitride framework;
- surface interaction with solvent molecules leading to understanding of possible exfoliation mechanisms.
The project will make extensive use of quantum chemical computational methods based on Density Functional Theory and energy minimisation techniques. Transition state searches for mechanistic studies will be applied through sampling the system energy along chosen reaction coordinates, such as the displacement of the centre of mass for mobile species. When appropriate, ab initio molecular dynamics (AIMD) calculations will also be employed to examine the mobility of intercalants within and between the layers. An additional goal of this reasearch will be to explore how results from AIMD simulations can be used to compare and rationalise experimental measurements using Quasi Elastic Neutron Scattering (QENS) techniques. Rational understanding of the structure-property correlation of the carbon nitride materials is critical for the optimisation of current properties, as well as the design of next generation compounds for specific energy related applications.
The project aligns with several EPSRC research Areas within the Physical Sciences Theme, including those on Materials for energy applications (grow), Chemical reaction dynamics (maintain) and Condensed-matter, electronic structure (maintain), with the former (materials for energy application) providing the closest match.