Hexagonal boron nitride (h-BN) “a miracle in white”: An emerging two-dimensional material for the advanced powered electronics and energy harvesting application

The growing demand for batteries or other compact electronics received considerable attention because of its high energy density and excellent power-to-mass ratio. However, obstacles such as inconsistent temperature distribution, inefficient energy storage, and sluggish release rates have emerged. Effective heat dissipation is required for optimum efficiency and durability of electrical devices. Thus, it is crucial to develop thermally conductive hybrid fillers for improved heat management in such systems. Two-dimensional (2D) hexagonal boron nitride (h-BN), also known as "white graphene," encounters conceivable uses in electronics and energy devices due to the broad bandgap (∼5.5 eV), superior thermal endurance, high thermal conductivity (TC), and exceptional dielectric properties. The anisotropic conductivity of BN causes a reduction in cross-plane TC, which is a fundamental concern for its practical deployments. Therefore, developing a unique technique and structural engineering remedy for enhancing BN's cross-plane TC could be achievable. The main focus of this article is to explore the phonon-phonon scattering phenomena, mechanisms, and insights to design h-BN-based composites with good cross-plane TC and electrical insulation. The article summarizes the significance of 2D h-BN in several sectors, including electronic packaging, energy (e.g., thermal energy management and conversion), and batteries/supercapacitors. These topics highlight cutting-edge filler properties and the innovative design of 2D h-BN. Finally, the challenges and perspectives of developing potential thermal interface materials (TIMs) are highlighted. Our insights offer an initial glimpse into future studies on fabricating advanced TIMs in an appropriate filler structure configuration for optimal cooling of electronic/optoelectronic devices.