Figure 3.

Self-powered electrochemical synthesis: (a) sketch map of the SP water splitting system; (b) structure of the disk TENG; (c) the SP water splitting system driven by a miniature water turbine; (d) images of the system with bubble producing [74]; (e) sketch map of the SP electrochemical system for CO₂ reduction powered by TENG for harvesting ocean-wave energy [70]; (f) sketch map of the designed TENG; (g) reaction of SP ammonia synthesis system; (h) sketch map of the SP structure driven by exhaust gas; (i, j) concentration of NH₃ in the cathode compartment at different times (i) and the volume of residual solution and the yield of NH₃ (j) by the SP system after ten hours [82].