Hetero-layered 2D materials: Scalable preparation and energy applications

Abstract

To be considered for use in practical energy storage and conversion applications, two-dimensional (2D) materials require a well-defined size distribution, large specific surface area, lightweight, and controllable crystallinity. In line with this, hetero-layered 2D (2D-HL) materials, comprising stacked layers with tailored compositions and structures, offer unique properties ideal for energy-related applications. However, the large-scale synthesis of uniformly sized 2D-HL materials with consistent characteristics remains a significant challenge. To address this, both top-down and bottom-up synthesis methods have been investigated, particularly with top-down exfoliation emerging as a reliable, cost-effective, and scalable technique. This review examines recent advancements in the synthesis of 2D-HL materials via various exfoliation processes, emphasizing the correlation between material structure and the selected exfoliation approach while evaluating the scalability of these methods. Understanding the principles that govern the synthesis and optimization of scalable 2D-HL materials is essential for overcoming current challenges and leveraging future opportunities in advanced energy storage applications. Furthermore, this review provides an in-depth analysis of the potential of physical exfoliation methods to produce 2D-HL materials with the properties necessary for energy storage and conversion applications.