The development of polymer electrolyte membrane electrolysis of water is mainly limited by the high cost of noble metals and inadequate stability owing to the slow reaction kinetics of the oxygen evolution reaction and the restrictions of strongly acidic operating environments. To improve the utilization of noble metals, we use Ti-doped SnO2 as a carrier to support active species IrO2. The results show that the introduction of Ti element can inhibit the grain growth and help to improve the electrical conductivity of SnO2. Electrochemical tests for the catalysts show that 40 wt % IrO2/TSO has the best mass-normalized charge (231.24 C g–1 IrO2) and current density (714.85 A g–1 IrO2) at 1.6 V with the overpotential of only 271 mV at 10 mA cm–2, which is attributed to the outstanding dispersion effect of Ti-doped SnO2 and the synergy between the active species and the introduction of Ti element. The comprehensive advantages exhibited by the Ti-doped SnO2 support provide an alternative solution to reduce the cost of noble metal catalysts by improving the catalytic activity and stability.

Transition-metal/heteroatom-doped carbon exhibits exceptional oxygen reduction reaction (ORR) catalytic activity in alkaline electrolytes, which is expected to replace noble metals as fuel cell cathode catalysts. The ORR activity of catalysts can be further improved by enriching active sites and enhancing the intrinsic activity of catalysts. Herein, phosphorus-rich porous polyaniline (P-PANi) gel is used as a precursor during heat treatment, and the characteristics of low boiling point (about 200 °C) and steric hindrance of ferrocene are introduced to synthesize high-dispersion iron-doped graphite catalysts. A series of as-synthesized Fe-N/P/C catalysts were obtained at various heat treatment temperatures. Fe-N/P/C-850 manifests the highest ORR activity and electrochemical stability, with an onset potential of 1.06 V and a half-wave potential of 0.86 V. The enhanced activity of Fe-N/P/C-850 is mostly attributed to the P–C junction due to the combination of phosphorus and carbon.

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Silicon has been considered as one of the most promising candidate anode material for Li-ion batteries due to its high theoretical specific capacity. Nevertheless, its low cycling performance due to the huge volume change during cycling hinders the commercial application of silicon anodes. Binders play a crucial role in Li-ion batteries and can effectively relieve the volumetric expansion stress of silicon anodes. Herein, we developed a polyimide binder with an introduced carboxyl group (PI-COOH). The introduced −COOH group can effectively bond with the oxide layer on the silicon surface through forming improved interface stability and then reducing the damage of the solid electrolyte interface film during cycling. Combined with the excellent intrinsic mechanical and thermodynamic properties of polyimide, the as-prepared PI-COOH binder significantly improved the cycling stability and rate performance of silicon anode.

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