Nanowerk November 2, 2023
Solar-driven evaporation rates using porous absorbers have been reported to exceed the theoretical thermal evaporation limit, but the mechanism of this phenomenon remains unclerogel materials was negligible. 2) Illumination of hydrogel under solar or visible-spectrum light-emitting diode led to evaporation rates exceeding the thermal evaporation limit, even in hydrogels without additional absorbers. 3) The evaporation rates were wavelength dependent, peaking at 520ar. Researchers at MIT found many unexpected results in their experiments: 1) Partially wetted hydrogels became absorbing in the visible spectral range, where the absorption by both the water and the hydrogel material is negligible. 4) Temperature of the vapor phase became cooler under light illumination and showed a flat region due to breaking-up of the clusters that saturated air. And 5) vapor phase transmission spectra under light showed new features and peak shifts. They hypothesized that photons in the visible spectrum could cleave off water clusters off surfaces due to large electrical field gradients and quadrupole force on molecular clusters, they called the process the photomolecular effect. According to the researchers photomolecuar might be happening widely in nature, potentially impacting climate, and plants’ growth, and can be exploited for clean water and energy technologies… read more. TECHNICAL ARTICLE
At the interface of water and air, light can, bring about evaporation…
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