Two-dimensional layered materials for triboelectric nanogenerators

Triboelectric nanogenerators (TENGs) have emerged as promising technology for harvesting mechanical energy from diverse sources, including human motion, vibrations, and environmental forces. Layered or two-dimensional materials, such as MXenes, graphene, carbon nanotubes, transition metal dichalcogenides (TMDs), metal–organic frameworks (MOFs), and covalent organic frameworks (COFs), have gained significant attention for their ability to enhance TENG performance through tailored electronic properties, surface functionalization, and structural modifications. This review provides a comprehensive overview of the latest advancements in TENGs utilizing layered materials, discussing their material design, triboelectric behavior, and integration strategies. Theoretical models explaining charge transfer mechanisms, charge trapping effects, and energy conversion efficiency are critically analyzed. Additionally, challenges related to material degradation, wear, environmental stability, and scalability are addressed, along with potential solutions, such as self-healing tribolayers and advanced energy management circuits. By bridging material science and triboelectric nanogenerator technology, this review highlights future directions for the development of high-performance, durable, and sustainable energy harvesting systems.