Non‐oxide cobalt‐based water‐oxidation electrocatalysts have received attention recently for their relative ease of preparation, they are stable both in acidic and basic media, and they have higher turnover frequencies than cobalt oxides. Recent studies show that one of the main bottlenecks in the implementation of non‐oxide systems to water splitting is the low number of active metal sites, which is in the order of nmol cm−2. Herein, a new series of non‐oxide water‐oxidation catalysts has been introduced to the field. Cobalt dicyanamides are observed to have around four times higher surface active sites and better catalytic performances than cyanide‐based systems. Long‐term catalytic studies (70 h) at an applied potential of 1.2 V and electrochemical studies performed in solutions in pH values of 3.0–12.0 indicate that the compounds are robust and retain their structures even under harsh conditions. Moreover, the addition of Ni impurities to cobalt dicyanamides is a feasible method to improve their catalytic activities.

Although cobalt‐based heterogeneous catalysts are the central focus in water oxidation research, interest in copper‐based water oxidation catalysts has been growing thanks the great abundance of copper and its biological relevance. Several copper oxides have recently been reported to be active catalysts for water oxidation. In this study, a heterogeneous copper‐based water oxidation catalyst that is not an oxide has been reported for the first time. Single‐crystal XRD studies indicate that the compound is a one‐dimensional coordination compound incorporating copper paddle‐wheel units connected through phosphine dioxide ligands. The catalyst exhibits an onset potential of 372 mV at pH 10.2, whereas an overpotential of only 563 mV is required to produce a current density of 1 mA cm−2. In addition to cyclic voltammetric and chronoamperometric studies, an investigation into the effect of pH on the catalytic activity and the robustness of the catalyst using long‐term bulk electrolysis (12 h) is presented.

Non–noble metal catalysts have recently emerged as promising alternatives to the expensive platinum catalysts for the oxygen reduction reaction (ORR). In this study, a new domain of materials, copper based coordination polymers, has been investigated as promising catalysts for ORR. The study was inspired by copper incorporating biomolecules, which efficiently catalyse the oxygen reduction reaction in nature. Two coordination polymers, [Cu2(μ−AcO)4Po)]n (shortened as[Cu–A]) and [Cu2(μ−BzO)4Po)]n (shortened as[Cu–B]), incorporating one–dimensional chains of Cu(II) paddle wheel units bridged with phosphineoxide ligands were combined with multi−walled carbon nanotubes (MCNTs) to prepare hybrid electrocatalysts for ORR. The electrochemical analysis demonstrates that [Cu–A] catalyses ORR with 3.24 numbers of electrons with Tafel slopes of 122/83 mV dec−1 while it is 2.37 numbers of electrons with Tafel slopes of 131/84 mV dec−1 for [Cu–B]. Rotating disk electrode measurements and evaluation of Tafel slopes reveal that acetate moieties attached to Cu site shift the onset potential of ORR anodically (ca. 40 mV) compared to the one with benzoate bridging groups. The effect of bridging ligands to the stability and activity of catalysts in alkaline media was also evaluated. This study opens a new perspective for the development of non–platinum ORR catalysts.

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