Marriage between metal-organic frameworks/covalent-organic frameworks and triboelectric nanogenerator for energy harvesting —A review

Nanogenerators defines by their unique property of scavenging attenuated mechanical energy by physical changes based on Maxwell's equation and frictional properties. Triboelectric nanogenerators (TENGs) are an essential class of nanogenerators working based on the combined effect of contact electrification and electrostatic induction. A triboelectric series forms of tribo- positive or -negative materials, which novel materials occupy nowadays. One such material is metal-organic frameworks (MOFs) with tailorable pore size and high chemical stability. This paper reviews the energy-scavenging ability of various MOF/covalent-organic framework (COF) family members to explore the novel connection between MOF/COF and TENG. The overall study is divided into two sections discussing MOF-TENG and COF-TENG, with MOF-TENG having the most recent applications. Shape, morphology, and physiochemical properties are discussed; a separate section is devoted to MOF/COF material design. The working mechanism of MOF/COF-TENG is described using the potential well model. The most crucial property of MOF/COF is the ability to make coordination bonds with the guest molecule, which will alter all the properties. Thus one can fine-tune MOF/COF according to the requirement of specific applications. In total, the MOF/COF-based TENG can bring a new revolution in almost all fields which is less explored is discussed as a future perspective in this review.