fig5

Figure 5. Material strategies to modulate multi-ion dynamics. (A) Schematics of the Janus channel; (B) Schematic of the ion diffusion in NP-MXene with the left side (C₁) being a high concentration of MgCl₂ and a low concentration of Na₂SO₄ solution and the right side (C₂) being a high concentration of Na₂SO₄ and a low concentration of MgCl₂ solution. This figure is quoted with permission from the American Association for the Advancement of Science^[72]; (C) Comparison of osmotic current densities for different types of MXene. This figure is quoted with permission from the American Association for the Advancement of Science^[72]; (D) Schematics of the bidirectional gel; (E) Schematic illustration of the DIG-enabled HEG structure. This figure is quoted with permission from the Royal Society of Chemistry^[73]; (F) Open-circuit voltage and short-circuit current of traditional HEGs and the DIG-enabled HEG. This figure is quoted with permission from the Royal Society of Chemistry^[73]. N-MXene: Negatively charged MXene; P-MXene: positively charged MXene; CSE: cation-selective electrolyte; ASE: anion-selective electrolyte; HEG: hydrovoltaic electricity generation; DIG: dual-interfacial gating.