Evaporating Potential in Conical PTFE Membrane with Asymmetric Electrodes

Abstract

Power generation from nature evaporation receives great attention since water evaporation is a ubiquitous process. However, the energy devices may not be the norm geometry that results in different flow and energy conversion behaviors. Here, a conical polytetrafluoroethylene (PTFE) hydrovoltaics generator with asymmetric electrodes is proposed to study the effect of membrane structures and electrodes matching on power generation. The asymmetric membrane structure optimizes the capillary flow that generate the more effective velocity in the top areas of generator, which induces a higher voltages sign. Meanwhile, the directed asymmetric electrodes synergize interfacial and streaming potentials. As a result, the forward conical structure with C-Cu electrodes obtains the optimal energy conversion performance. Subjecting such device to environmental conditions, it can induce a ~0.4 V open circuit voltage and remains stable for around 20 hours without noticeable fluctuations. The facile structure and electrodes matching optimizes the power generation, providing valuable insights to sustainable energy harvesting.