Materials for evaporation?driven hydrovoltaic technology

Water constitutes the largest energy carrier on earth, absorbing more than 70% of solar received by earth's surface, yet its low exploitation has been a constant concern. The hydrovoltaic effect is an emerging technology that generates electricity through direct interaction between nanomaterials and water various forms (raindrops, waves, flows, moisture, natural evaporation). Especially, evaporation-driven spontaneous ubiquitous process can directly convert thermal from surrounding environment into without demand for additional mechanical work, which shows unique advantages compared with other effects. A variety nanostructured materials have steadily developed devices (EHDs) in recent years. However, there lack clear specification selection design improving device performance. Herein, we first analyze mechanisms EHDs followed summarization advances materials, including carbon biomass-based metal oxides, composite others. We then discuss strategies conversion efficiency output power terms structural design, surface modification, interface treatment. Finally, provide outlook potential applications generation, sensors, desalination technology, as well challenges prospects development this future.