Water-Enabled Electricity Generation by a Smooth Liquid-Like Semiconductor Coating Surface.

Water energy-converting techniques that focus on interfacial charge separation and transfer have aroused significant attention. However, the water-repelling nature leads to a less dense liquid layer and a sharp gradient of liquid velocity, which limits its output performance. Here, a water sliding generator (WSG) based on a smooth liquid-like/semiconductor surface (SLSS) is developed that harnesses the full advantage of liquid sliding friction. The prepared SLSS not only retained the slippery surface's close contact with liquid droplets and the characteristic of sliding without residue but also exhibited an enhanced friction effect on the low-friction surface. The smooth liquid-like/semiconductor surface water sliding generator (SLSS-WSG) exerts outstanding liquid sliding friction energy harvesting with high output (≈16 V and ≈60 µA) demonstrated, capability in series connection, dual operation of power generation and self-cleaning effect, and high physical and chemical stability (continuous current scour and sun exposure). The prepared surface can be integrated with photovoltaic panels, enabling them to generate electricity from water-sliding energy during rainy days, compensating for the reduced output of photovoltaic panels during overcast and rainy weather. Furthermore, it allows for energy collection even during rainy nights. The prepared surface can be potentially applied in various fields, showing great potential for the development of water-based clean energy.