Power generation by converting energy from the ambient environment has been considered a promising strategy for developing decentralized electrification systems to complement the electricity supply for daily use. Wet gases, such as water evaporation or moisture in the atmosphere, can be utilized as a tremendous source of electricity by emerging power generation devices, that is, moisture‐enabled‐electric nanogenerators (MEENGs). As a promising technology, MEENGs provided a novel manner to generate electricity by harvesting energy from moisture, originating from the interactions between water molecules and hydrophilic functional groups. Though the remarkable progress of MEENGs has been achieved, a systematic review in this specific area is urgently needed to summarize previous works and provide sharp points to further develop low‐cost and high‐performing MEENGs through overcoming current limitations. Herein, the working mechanisms of MEENGs reported so far are comprehensively compared. Subsequently, a systematic summary of the materials selection and fabrication methods for currently reported MEENG construction is presented. Then, the improvement strategies and development directions of MEENG are provided. At last, the demonstrations of the applications assembled with MEENGs are extracted. This work aims to pave the way for the further MEENGs to break through the performance limitations and promote the popularization of future micron electronic self‐powered equipment.

As an emerging candidate for a sustainable power supply, moisture-electric generators (MEGs) have attracted great attention in recent years. Unlike the conventional hydroelectric system, MEGs propose to harvest energy from ambient moisture, driven by either ion diffusion under a concentration gradient or the interaction between a solid–liquid interface governed by electrostatic theory. Two-dimensional (2D) nanomaterials, in particular hydrophilic graphene oxide (GO), have been considered as the most promising materials for high-performance MEGs owing to their unique structure and properties. In line with the development of 2D nanomaterials, the recent electrical output of a single MEG has been greatly raised from tens to hundreds of millivolts, which is capable of powering commercial electronics. Herein, we have reviewed the recent progress of 2D nanomaterials in MEGs. The mechanism of moisture-induced electricity generation and strategies for tailoring 2D nanomaterials to enhance the output performance of MEGs are discussed. The potential application of MEGs is also discussed in two categories: sensing and power supply. Finally, the existing challenges and the perspective of MEGs are proposed for future study.