# Microanalysis of single-layer hexagonal boron nitride islands on Ir(111)

## TL;DR

This study investigates the growth, structure, and properties of single-layer hexagonal boron nitride islands on Ir(111), revealing how temperature and substrate morphology influence their formation and electronic characteristics.

## Contribution

It provides new insights into the structural and electronic differences of hBN islands on Ir(111), and how synthesis temperature affects their growth and surface chemistry.

## Key findings

- Two types of hBN islands differ in shape and orientation.
- Different work functions and bindings were observed for the two island types.
- Higher temperatures lead to additional reconstructed regions on hBN islands.

## Abstract

Large hexagonal boron nitride (hBN) single-layer islands of high crystalline quality were grown on Ir(111) via chemical vapor deposition (CVD) and have been studied with low-energy electron microscopy (LEEM). Two types of hBN islands have been observed that structurally differ in their shape and orientation with respect to iridium, where the former greatly depends on the iridium step morphology. Photoemission electron microscopy (PEEM) and IV-LEEM spectroscopy revealed that the two island types also exhibit different work functions and bindings to iridium, which provides an explanation for differences in their shape and growth modes. In addition, various temperatures were used for the CVD synthesis of hBN, and it was found that at temperatures higher than ~950 {\deg}C boron atoms, originating either from decomposed borazine molecules or disintegrated hBN islands, can form additional compact reconstructed regions. The presented results are important for advancement in synthesis of high-quality hBN and other boron-based layered materials, and could therefore expedite their technological implementation.