Ammonia oxidation reaction (AOR) is an environmentally friendly electrochemical technology for hydrogen production. Nowadays, exploiting low-costing, high-performance and robust catalysts for AOR is essential to improve the overall efficiency of ammonia electrolysis cell (AEC). Here, we report the synthesis and characterization of a novel free-standing three-dimensional (3D) porous N-doped graphene aerogel (NGA) anchored with Pt nanocluster (Pt/ NGA) monolithic material as a high-performance and robust electrocatalyst for hydrogen production from AEC. The NGA substrate was facilely fabricated through a self-assemble process into the randomly arranged 3D porous backbone structure with graphene oxide (GO) and poly(oxypropylene)diamine D400 as precursors in a pure water solvent. Then, the Pt nanocluster-like structures were uniformly dispersed and embedded onto NGA through the simple electrodeposition method. The as-prepared Pt/NGA monolithic materials exhibited a higher ammonia electro-oxidation activity with the mass activity of 1.77 mA μg −1 Pt and the specific activity of 0.64 mA cm −2 ECSA , due mainly to the uniformly dispersed Pt nanocluster-like morphology, the improved electrical conductivity, the 3D porous NGA networks as well as the N-doping structure in graphene framework. When the 3D Pt/NGA monolith was directly used as working electrodes of AEC, a considerable hydrogen volume of 8.5 mL (about 1.90 mL mg −1 Pt ) was produced at 0.8 V in 3 h. This novel free-standing 3D porous NGA monolith is expected to be a potential and promising material for application in the fields of electrocatalysis and electrochemical energy transform.

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A chitosan cross-linked poly(1,5-diaminoanthraquinone)/Prussian blue (PDAA/PB) ternary nitrogen precursor-derived Fe–N–C/800-HT2 catalyst shows highly efficient ORR activity for MFCs and Zn–air batteries.

Platinum and iridium co-supported on N-doped reductive graphene oxide (N-rGO) electrocatalysts (PtÀIr/N-rGO) were synthesized and investigated for ammonia electro-oxidation reaction (AOR) in alkaline media. Pt and Ir particles were deposited over the N-rGO substrate through a potentiodynamic electrodeposition method. The deposition parameters, lower potential limit (E L ) and scan rate, play a vital role on the dispersion degree and particle size of PtÀIr bimetallic nanoparticles over N-rGO. Additionally, the comparable current densities and a better poisoning inhibition are obtained compared to the commercial Pt (20 wt%)/C indicating that a synergistic effect among Pt, Ir and N-rGO substrate is existing in favour on the electrocatalytic activity. The N-rGO substrate with more active sites, higher excellent electrochemical activity and well dispersion for Pt and Ir particles anchoring is a suitable substrate for AOR and would be extended to other catalytic reactions.[a] Dr.