fig15

Figure 15. (A) Schematic of an ionic polymer-hydrogel-carbon composite (IPHC) device. (B) V_oc of an IPHC and corresponding RH profile in response to moisture flow. (C) Intermittent supply of moisture flows (every 3 s) to an IPHC device and its voltage output. (D) Left: Schematic of an IPHC in the initial dry state. From left to right is carbon paper, Nafion, pNIPAm, and pored carbon paper. Right: in response to moisture flow, the concertation gradient of H₂O and H⁺ is built across the IPHC. (E) Voltage signals recorded by the IPHC corresponding to human breath through nose and mouth. (F) Magnified figure of the red-square region in (E). (G) Change in relative humidity (black curve) and temperature (grey curve) for (G₁) nasal breathing and (G₂) mouth breathing. (H) Voltage signals and flow rates when the moisture spray was applied to an IPHC intermittently. (I) Voltage signals of an IPHC in response to the moisture flow generated simultaneously with cooling a hot steel sheet through the water. Reprint with permission Ref.^[9]. Copyright 2022, The Royal Society of Chemistry.