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Non-precious metal catalysts (NPMCs) doped with nitrogen were derived from MOFs. Appropriate ligand and framework order in the precursor ensured the presence of various nitrogenous species and high surface area in the NPC, Ni-NPC, Co-NPC, and Fe-NPC electrocatalysts. Electrochemical properties of the as-prepared electrocatalysts were examined in 0.1 M KOH solution to investigate the effects of metal and doped nitrogen on the oxygen reduction reaction (ORR). The free metal electrocatalyst (NPC) displayed poor ORR activity with an onset potential of 0.87 V RHE. The presence of nickel in the Ni-NPC catalyst could not create more active sites in comparison with the NPC catalyst, while onset potential of the Co-NPC catalyst shifted to 21 mV more positive (Compare to NPC). The investigation of doping active transient metals indicated that Fe-doping could be effective. It was because of the improved ORR activity of the Fe-NPC electrocatalysts with an onset potential of 0.99 V RHE. Furthermore, in a long-term stability test, this optimum electrocatalyst could retain more than 92% of its initial current density and experienced just 57 mV loss in its half-wave potential in an accelerated degradation test. Direct ethanol fuel cell test reveals maximum power density of 19.2 mW cm−2 at ambient temperature. • New M-NPS electrocatalysts were synthesized by pyrolysis of effective MOF precursors. • The synthesized M-N-C electrocatalysts had high surface area and a variety in nitrogenous species. • The effect of the metal on the activity and stability of the M-N-C electrocatalysts was evaluated for ORR. • The sequence of the catalysts activity in ORR are: FeN x > CoN x > NiN x ∼ metal free-N x. [ABSTRACT FROM AUTHOR]

To fabricate effective and stable OER electrode in water electrolysis, self-doped TiO 2 nanotube arrays which has a higher electrical conductivity than pristine TiO 2 nanotube arrays was used as the support for loading IrO 2 . The self-doped TNTA was fabricated by a simple electrochemical reduction of TNTA in neutral electrolyte solution, and then IrO 2 nano particles were deposited by pulse electro-deposition method. The cyclic voltammetric behavior, electrical conductivity and micro structure of self-doped TNTA prepared at different reduction potential were characterized to obtain an optimal performance, and self-doped TNTA prepared under −1.9 V (vs. Ag/AgCl) shows the best electrochemical performance. After depositing IrO 2 , the OER activity and stability of new electrodes were also determined. Due to the enhanced electrical conductivity of support, the mass activity of IrO 2 /self-doped TNTA are 50 times higher than IrO 2 /TNTA. The OER stability of new electrode was evaluated under constant current of 5 mA/cm 2 , IrO 2 /TNTA and IrO 2 /Ti were also tested for comparison. A higher stability of IrO 2 /self-doped TNTA electrode is observed than the other two electrodes, and XPS studies indicate a lower oxidation state of Ir in IrO 2 /self-doped TNTA, this shows a possible interactions between IrO 2 and the new support. [ABSTRACT FROM AUTHOR]