Abstract
<jats:p> Evaporating water droplets are known to acquire net charge, and the air–water interface to carry a collective net negative charge; yet the causal role of charge in evaporation itself has received comparatively little attention. While prior studies have addressed charge separation via ion diffusion at the phase front or external-field-induced polarization, these approaches treat charge as a consequence of — or an external input to — the phase transition, rather than as its trigger. Here, we propose that when charge is redistributed at the hydrogen-bonding sites of interfacial H <jats:sub>2</jats:sub> O molecules — specifically at the hydrogen atoms connecting to the oxygen atoms of sub-interfacial H <jats:sub>2</jats:sub> O molecules below — by external influences such as electric fields, contact, or thermal agitation, the resulting negative charge activation generates Coulombic repulsion sufficient to sever the hydrogen bond and expel the molecule into the gas phase. To test this hypothesis, we conducted four experiments: (i) container opening geometry, (ii) a modified gold-leaf electroscope, (iii) closed-circuit bottle configurations, and (iv) applied low voltage (0.10–0.20 V). The gold-leaf electroscope experiment indicated net charge transfer during phase transition; the closed-circuit copper wire experiment showed that charge dissipation suppressed evaporation by ~18%; and the low-voltage experiment showed that evaporation progressively increased (+0.063% → +0.275%) with stepwise voltage increase (0.10 → 0.20 V). These results indicate that charge redistribution at the hydrogen-bonding sites of interfacial H <jats:sub>2</jats:sub> O molecules is a factor influencing evaporation, with implications for evaporation-driven energy harvesting. </jats:p>