Role of Doped Nitrogen in Graphene for Flow‐Induced Power Generation

Abstract

Flow-induced power generation using nanomaterials, for example, graphenewater interface, has become an attractive energy harvesting mechanism. The effect of heteroatom doping of graphene on flow-induced electricity is investigated by the authors. Nitrogen-doped graphene is shown to generate 1.5 times higher power compared with pristine graphene due to surface charges and increase in effective interfacial area. Thus, doping-induced surface tuning of graphene enhances output performance. The flow-induced power generation using doped-graphene allows relaxing the material selection constraints in the triboelectric series.

Effects of Surface Functional Groups on Electron Transfer at Liquid–Solid Interfacial Contact Electrification

“…Since that the CE may lead to discharge and explosion, it was always considered as a negative effect, until the invention of triboelectric nanogenerators (TENGs) to convert mechanical energy into electricity. − Owing to the invention of TENGs, the interest in CE is rekindled. Various methods were proposed to increase the surface charge transfer between two contact materials, , and the mechanism of CE was widely discussed. − It was demonstrated that the CE highly depends on the functional groups on the material surfaces, , and the output performance of both solid–solid TENGs − and liquid–solid TENGs − can be optimized by modifying functional groups on the solid surfaces. However, the mechanism of the chemical functional group contributions on the CE is still under debate, especially for the liquid–solid cases.…”

Mixed-Dimensional van der Waals Heterostructures for Boosting Electricity Generation

“…5 The generation of the generators are capable of yielding high levels of instantaneous power density with relatively facile device configurations, the energy conversion efficiency of hydrovoltaic generators is still being pursued by exploring different low-dimensional functional materials 5−10 and designing distinctive device structures. 11 In addition to the feasibility of substitutional doped graphene to enhance electricity generation, 12,13 it has been demonstrated experimentally and theoretically that the graphene substrate is equally significant for regulating the output performance of graphene-based flow-induced generators. 14−18 Notably, when mentioning the substrate effect of graphene, it inevitably involves the transfer of graphene onto the target substrate to exploit its properties.…”

“…Although droplet flow-induced generators are capable of yielding high levels of instantaneous power density with relatively facile device configurations, the energy conversion efficiency of hydrovoltaic generators is still being pursued by exploring different low-dimensional functional materials − and designing distinctive device structures . In addition to the feasibility of substitutional doped graphene to enhance electricity generation, , it has been demonstrated experimentally and theoretically that the graphene substrate is equally significant for regulating the output performance of graphene-based flow-induced generators. − Notably, when mentioning the substrate effect of graphene, it inevitably involves the transfer of graphene onto the target substrate to exploit its properties. , So far, traditional wet transfer is the most widely adopted and straightforward strategy regarding the assembly of generators. ,,,, Despite the progress therein, this transfer procedure is not only tedious but also likely to introduce polymer residues and mechanical/chemical defects, resulting in significant degradation of the device performance. − Because of this, further attempts, such as generators based on directly grown graphene free of transfer-related contaminants, unavoidable damage, and corrugation, exhibited higher induced voltage and excellent long-term durability . However, the current directly grown graphene tends to suffer from low crystal quality, abundant structural defects, and inferior thickness uniformity, leading to poor electronic characteristics, which hinders the prospects for applications in energy harvesting .…”

Charge Exchange and Transfer between Water and van der Waals Monolayers Under Tensile Strains

“…Two-dimensional (2D) van der Waals (vdW) monolayers such as graphene, hexagonal boron nitride (h-BN), and transition metal dichalcogenides (TMDs) possess exceptional mechanical, physical, and chemical properties (e.g., high elastic modulus and charge mobility, , and excellent electrical/thermal conductivity , ). Experimental studies have shown that electricity power can be generated when water flows or water droplets move over the surfaces of graphene, − h-BN, or MoS 2 , − or when those 2D materials are in water evaporation and moisture. − The vdW monolayers exhibit the potential to be applied in nanogenerators for harvesting electricity energy from water in a sustainable and green manner. Charge exchange and transfer between water and vdW monolayers play key roles in electricity generation.…”