Synthesis and characterization of boron nanosheets by electrochemical exfoliation of amorphous boron

Abstract

Boron nanosheets are a promising material for energy, sensor and various biomedical applications. Preparation of boron nanolayers by depositing them on metal surfaces limits scalable production and reduces the potential for commercialization. Therefore, it is very important to develop a practical process to produce highly efficient and scalable boron consisting of several layers. The purpose of this study is produce boron nanosheets from amorphous boron using a unique, scalable electrochemical exfoliation method. In this method, amorphous boron was exfoliated anodically in a two-electrode setup using a mixture of sodium sulfate (Na2 SO4) and glycerin. Exfoliation was performed at +20, +30, and +40 V in 0.5 M Na2 SO4 to which glycerin was added (1:1 volume ratio) to increase viscosity. Structural characterization of boron nanosheets was examined by scanning electron microscopy (SEM), high resolution transmission electron microscopy (HRTEM), Fourier transform infrared spectroscopy (FT-IR), X-ray photoelectron spectrometer (XPS), micro-Raman, X-Ray diffractometry (XRD) and atomic force microscopy (AFM) analyses. The average thickness of boron nanosheets exfoliated at 20 V was 15.1 nm, while exfoliation at 30 and 40 V led to average thickness values of 15.3 and 14.5 nm, respectively. The average lateral size of boron nanosheets exfoliated at 20 V is 319 nm which is larger than those that exfoliate at 30V (252 nm) and 40 V (275 nm). HRTEM images show that several nanosheets of boron are formed. When different voltage values are compared, it is possible to say that the most effective exfoliation occurs at 20 V and the boron nanosheets at this value have a relatively lower thickness. © 2024, Turkish Energy, Nuclear and Mining Research Agency. All rights reserved.