Synthesis, characterization of hexagonal boron nitride nanoparticles decorated halloysite nanoclay composite and its application as hydrogen storage medium

• Lightweight and compact hydrogen storage material using A-HNT and h-BN is prepared.
• Facile ultrasonication method is adopted for synthesize of A-HNT-h-BN nanoclay composites.
• Hydrogen storage capacity of 2.88 wt% is achieved at 50 °C.
• 100% desorption of stored hydrogen is noticed.
• The observed binding energy of stored hydrogen lies in the recommended range of US DOE target.

In the emerging front of research, much attention is focused on the usage of hydrogen as a promising alternative energy carrier that can potentially replace fossil fuels. Conversely, the realization of hydrogen as an energy carrier becomes impounded since the light weight and compact hydrogen storage materials are still prerequisites for hydrogen fuel cell technology. In the present study, the performance of nanoclay composites composed of acid treated halloysite clay nanotubes (A-HNTs) and hexagonal boron nitride nanoparticles (h-BN) are investigated towards hydrogen storage. where facile ultrasonic approach was adopted. The prepared A-HNT–h-BN nanoclay composites subjected to various characterization techniques such as X-ray Diffraction (XRD), micro–Raman Spectroscopy, Fourier Transform Infrared Spectroscopy (FTIR), UV–Visible Diffuse Reflectance Spectroscopy (DRS), Scanning Electron Microscopy (SEM) with Energy Dispersive X-Ray Spectroscopy (EDX) and High Resolution Transmission Electron Microscopy (HRTEM) with Selected Area Transmission Electron Diffraction (SAED). The presence of h-BN nanoparticles at the surface of A-HNTs can be seen from HRTEM images and these findings are supported by XRD, FTIR and Raman results. Hydrogen adsorption studies are performed using Sieverts-like hydrogenation setup. A 2.88 wt% of hydrogen storage capacity and 100% desorption were achieved for the A-HNT–5wt% h-BN nanoclay composite at 50 °C. The adsorbed hydrogen possess the average binding energy of 0.33 eV, which lies in the recommended range (0.2–0.4 eV) for fuel cell applications. So it is expected that A-HNT–h-BN nanoclay composites will serve as a better hydrogen storage material for fuel cell applications in the near future.