Tuning Nanopore Shapes in 2D Materials via the Chemical Environment

–Ashmita Gupta

2D materials – crystalline sheets just a few atoms thick – have made waves in the field of nanotechnology. Their mechanical strength, electronic tunability, and atomic thinness make them ideal for applications ranging from water purification and biosensing to flexible electronics and catalysis. Among these, molybdenum disulphide (MoS₂) stands out for its semiconducting properties and versatile chemistry.

What makes materials like MoS₂ especially useful is the ability to introduce and control defects, particularly nanopores (atomic-scale holes on the surface of the material). However, accurately predicting how these pores form, what shapes they take, and how to control them has remained a challenge.

In a recent study, researchers from the Department of Chemical Engineering at IISc have developed a new computational framework that accurately models the formation and evolution of nanopores in 2D MoS₂. The work, carried out by Sayan Bhowmik and Ananth Govind Rajan, combines advanced atomic “fingerprinting” with quantum-mechanical simulations, stochastic modeling, and graph theory.

The team introduced a novel atomic fingerprinting scheme that labels undercoordinated atoms based on their bonding environment. These fingerprints are used to guide density-functional-theory (DFT) calculations and kinetic Monte Carlo (KMC) simulations, allowing modelling of pore growth atom by atom.

The team found that tuning the chemical potential of sulphur (S) allows fine control over pore shape and growth rate. Under molybdenum-rich conditions, pore growth was rapid, and pore shapes varied widely. In contrast, sulphur-rich environments fostered slower formation of triangular nanopores with high symmetry. The team also used data-driven mapping to highlight the most probable pore shapes under different chemical regimes.

Such an approach can also be applied to other similar materials like tungsten disuphide or molybdenum diselenide. The ability to programme nanopore shape and formation can lead to novel applications in seawater desalination, DNA sequencing, gas separation, and nanoelectronic device fabrication.

REFERENCE:

Bhowmik S, Govind Rajan A, Size and Chemical Environment Control Nanopore Geometry in 2D (MoS₂): From Irregular to Triangular Defects, Small (2025).
https://onlinelibrary.wiley.com/doi/10.1002/smll.202504611

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