# Controlled synthesis of two-dimensional porous molybdenum nitride via a stepwise nitridation growth mechanism

## TL;DR

Scientists developed a new method to create 2D molybdenum nitride structures with controlled properties for use in catalysis and energy storage.

## Contribution

A stepwise nitridation growth mechanism was introduced to synthesize 2D molybdenum nitride with defined morphology and reactivity.

## Key findings

- A well-ordered 2D γ-Mo2N structure was successfully fabricated on Al2O3(0001) substrates.
- The material's surface is rich in active sites, showing strong interactions with oxygen-containing molecules.
- The VSS growth mechanism was identified as critical for thin film nitride synthesis.

## Abstract

Transition metal nitrides exhibit desirable performance in various fields such as catalysis and energy storage due to their noble-metal-like properties. However, the controllable synthesis of two-dimensional (2D) planar metal nitrides with well-defined surfaces remains a challenge. Here, we report the controlled construction of molybdenum nitride model structures through stepwise nitridation using (NH4)6Mo7O24 as the precursor via chemical vapor deposition combined with a vapor–solid–solid (VSS) growth mechanism. Scanning electron microscopy (SEM), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS) confirmed the successful fabrication of a well-ordered, 2D planar porous γ-Mo2N model structure on Al2O3(0001) substrates. By optimizing growth conditions, we achieved controllable synthesis of material morphology and structure. Raman spectroscopy analysis revealed that the prepared γ-Mo2N surface is rich in active sites, demonstrating significant interactions with adsorbed oxygen-containing small molecules, which confirms its excellent surface reactivity. This study provides a novel strategy for preparing model structures of transition metal nitrides and elucidates the critical role of the VSS mechanism in nitride thin film growth.

Transition metal nitrides exhibit desirable performance in various fields such as catalysis and energy storage due to their noble-metal-like properties.