Exfoliation and Characterization of Two Dimensional TiB2 Nanosheets

Abstract

The substance known as 2D TiB2 is a newly discovered two-dimensional material. Liquid Phase Exfoliation (LPE) is widely recognized for its efficacy in exfoliating 2D TiB2. This method is particularly suitable for meeting the requirements of large-scale industrial production. However, most of the currently available liquid-phase exfoliation (LPE) procedures require the utilization of harmful and expensive solvents for the chemical exfoliation of the two-dimensional (2D) sheets prior to their mechanical (ultrasonic) dispersion. In the present study, a comparison was conducted to assess the impacts of two dispersive mediums, namely NMP and DI Water. Subsequently, we conducted an analysis on the effects of significant ultrasonic (US) LPE parameters, namely Input Power and US Treatment Time, to control the efficient production and enhance the quality of few layered 2D TiB2 sheets within a limited duration, particularly in a pristine aquatic setting. The findings of our study indicate that the liquid phase exfoliation (LPE) process in N-methyl-2-pyrrolidone (NMP) consists of three distinct steps, whereby contaminants are present in the exfoliated sheets. This characteristic renders the procedure time-consuming and expensive. In contrast, the liquid phase exfoliation (LPE) technique employed in this study was shown to be a one-step procedure that yielded defect-free, highly pure, and systematically exfoliated sheets. Consequently, this approach is considered as environmentally friendly, devoid of impurities, and cost-effective. The key factors that influence the reduction of layer thickness, lateral dimensions, and manufacturing yield of 2D TiB2 include the input power of an ultrasonic (US) source, a higher intensity of acoustic cavitation, an optimal duration of US treatment, and a uniform distribution of cavitation events achieved by employing a suitably sized sonotrode within the sonicated volume. This work offers a means to enhance the LPE methodology as a financially feasible, environmentally friendly, and readily scalable manufacturing approach for the large-scale commercial production of 2D TiB2. These 2D TiB2 sheets may be applied in several domains such as energy storage, water splitting, and catalytic processes.