Echinops‐like bimetallic CoNiP−CoNi alloy is synthesized from a metal−organic framework (MOF) and serves as an efficient catalyst for the oxygen evolution reaction (OER), with a low overpotential of 300 mV in 1 M KOH at 10 mA cm−2 (η10). The cooperative effect of Ni and Co metal, as well as the interfacial properties of the integrated semiconducting phosphide/metallic alloy and electronic conductivity of the MOF‐derived carbon regulate the performance of the catalyst. Moreover, the bimetallic CoNiP/CoNi alloy catalyst is interspersed with N‐doped graphene, forming a triad catalyst that demonstrates superior activity towards the hydrogen evolution reaction (η10=150 mV) and excellent durability, owing to interfacial effects of the triad catalyst, large electrochemical active surface area, and enhanced conductivity from N‐doped graphene. The stability of the carbon‐containing catalyst during OER (oxidation) is altered by the high reactivity of heteroatom dopant. The assembled CoNiP/CoNi/N−RGO||CoNiP/CoNi water electrolyzer delivers a reasonable cell potential of 1.76 V at 10 mA cm−2. The synthesized bimetallic CoNiP/CoNi alloy‐based triad catalyst thus demonstrates excellent electrocatalytic activity and high durability suitable for efficient alkaline water splitting.

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Polypyrrole (PPy)/cellulose (PPCL) composite papers were fabricated by vapor phase polymerization. Importantly, the vapor-phase deposition of PPy onto cellulose was assisted by employing different co-vapors namely methanol, ethanol, benzene, water, toluene and hexane, in addition to pyrrole. The resulting PPCL papers possessed high mechanical flexibility, large surface-to-volume ratio, and good redox properties. Their main properties were highly influenced by the nature of the co-vaporized solvent. The morphology and oxidation level of deposited PPy were tuned by employing co-vapors during the polymerization, which in turn led to change in the electrochemical properties of the PPCL papers. When methanol and ethanol were used as co-vapors, the conductivities of PPCL papers were found to have improved five times, which was likely due to the enhanced orientation of PPy chain by the polar co-vapors with high dipole moment. The specific capacitance of PPCL papers obtained using benzene, toluene, water and hexane co-vapors was higher than those of the others, which is attributed to the enlarged effective surface area of the electrode material. The results indicate that the judicious choice and combination of co-vapors in vapor-deposition polymerization (VDP) offers the possibility of tuning the morphological, electrical, and electrochemical properties of deposited conducting polymers.

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