Water‐Enabled Electricity Generation: A Perspective

Abstract

Harvesting energy from the environment offers many opportunities for the generation of clean power from self‐sustained systems and provides great promise for ameliorating the growing threat of the global environmental issues and the energy crisis. Ambient moisture and natural water sources have attracted huge research interest in the field of energy harvesting and conversion due to easy access, good sustainability, and the ubiquity of water on Earth. Taking advantage of the active interaction between water molecules and solid interfaces, various functional materials have been demonstrated to harvest energy and generate useable amounts of electrical power from water. In this review, some perspective on the development of water‐enabled electricity generation is given. The current preferred methods for water‐enabled electricity generation and relevant functional materials are summarized. Also, how the development of new materials and systems has led to significant improvements in the electrical power output reported for these devices is discussed. Then, some recent advances that have resulted in dramatic increases in the electrical output available from water‐enabled electrical generators (WEEGs) is discussed. Finally, some future trends in the development of WEEGs are outlined, and how this may result in practical applications and commercialization of these devices is shown.

Gradience Free Nanoinsertion of Fe3O4 into Wood for Enhanced Hydrovoltaic Energy Harvesting

“…Water evaporation-induced electricity is a new topic with limited understanding of the working mechanisms. Streaming potential, , evaporation potential, ionovoltaic voltage generation, and so on have been proposed, yet it is commonly agreed that streaming potential is the main contribution. For this specific case, the mechanism is even more complicated as solar irradiation is applied and Fe 3 O 4 could potentially be a catalyst for reactions under solar irradiation.…”

“…Water is the largest energy carrier on earth, containing around 35% of solar energy received by the Earth, corresponding to over 2000 times the world energy demand . Renewable energy harvesting from water using nanomaterials and nanotechnologies has attracted wide attention. − Hydrovoltaic energy harvesting, water evaporation-induced electricity generation in particular, is promising owing to the considerable energy embedded in the universal evaporation process (around 2/3 of water energy), applicability to a wide range of materials (such as carbon nanomaterials, , Ni–Al alloy, , polymers, and metal–organic frameworks), and easy device fabrication where the electrodes can be used multiple times. ,, Electricity generation relies on the interactions between water and materials, mainly based on the classical streaming potential, , which is electrical potential generation by driving water through a narrow channel under pressure gradience. Power generation is strongly influenced by the materials’ surface chemistry, which governs the interfacial charging/discharging, ,, materials’ nanoporous structure, and water evaporation rate .…”

A simple self-powered sensor for the detection of D2O and other isotopologues of liquid water

“…Heterogeneous surface potential and blockage of streaming potential A streaming current produced as a liquid ows through a charged micro-/nano-channel, has been a common source for water-enabled electricity generation [30][31][32][33][34] . The surface charge of a solid in liquid medium derives from the ionization or dissociation of surface groups, adsorption of ions from solution, or chemical substitution of surface groups 35,36 nanoparticles and the interface between adjacent particles in nanoporous Al 2 O 3 structure (Supplementary Fig.…”

Advances in harvesting water and energy from ubiquitous atmospheric moisture

“…Water and energy extraction from moisture has become a hotbed of research with a surge in the number of publications reviewing advances in atmospheric water and energy generation technologies. [14][15][16][17][18][19][20][21][22][23][24][25][26] However, most of these review papers either discuss the water and energy strategies separately or one type of energy conversion, without establishing an association between these strategies.…”