Influence of vacancy defects on 2D BeN4monolayer for NH3adsorption: a density functional theory investigation

Seetha Lakshmy; Gopal Sanyal; Nandakumar Kalarikkal; Brahmananda Chakraborty

doi:10.1088/1361-6528/acea28

Influence of vacancy defects on 2D BeN₄monolayer for NH₃adsorption: a density functional theory investigation

Nanotechnology. 2023 Aug 14;34(43). doi: 10.1088/1361-6528/acea28.

Authors

Seetha Lakshmy^{1

2}, Gopal Sanyal³, Nandakumar Kalarikkal^{1

4

5}, Brahmananda Chakraborty^{6

7}

Affiliations

¹ International and Inter University Centre for Nanoscience and Nanotechnology, Mahatma Gandhi University, Kottayam 686 560, Kerala, India.
² Chemical Engineering Division, Bhabha Atomic Research Centre, Trombay, Mumbai-400085, India.
³ Mechanical Metallurgy Division, Bhabha Atomic Research Centre, Trombay, Mumbai-400085, India.
⁴ School of Pure and Applied Physics, Mahatma Gandhi University, Kottayam 686 560, Kerala, India.
⁵ School of Nanoscience and Nanotechnology, Mahatma Gandhi University, Kottayam 686 560, Kerala, India.
⁶ High Pressure and Synchroton Radiation Physics Division, Bhabha Atomic Research Centre, Trombay, Mumbai-400085, India.
⁷ Homi J Bhabha National Institute, Bhabha Atomic Research Centre, Trombay, Mumbai-400085, India.

PMID: 37489852
DOI: 10.1088/1361-6528/acea28

Abstract

Two-dimensional materials have attracted a great deal of interest in developing nanodevices for gas-sensing applications over the years. The 2D BeN₄monolayer, a recently synthesized single-layered Dirac semimetal, has the potential to function as a gas sensor. This study analyzes the NH₃sensing capacity of the pristine and vacancy-induced BeN₄monolayers using first-principles density functional theory (DFT) calculations. As per the results, the NH₃molecule is physisorbed on the pristine BeN₄via weak Van der Waals interaction with a poor adsorption energy of -0.41 eV and negligible charge transfer. Introducing Be vacancy in BeN₄increased the NH₃adsorption energy to -0.83 eV due to the improved charge transfer (0.044 e) from the defective monolayer to the NH₃molecule. The structural stability, sufficient recovery time (74 s) at room temperature, and superior work function sensitivity promise the potential application of defective BeN₄as an NH₃sensor. This research will be a theoretical groundwork for creating innovative BeN₄-based NH₃gas sensors.

Keywords: ammonia sensing; first-principles simulations; monovacancy; recovery time; work function.