Pulse electrodeposited, morphology controlled organic–inorganic nanohybrids as bifunctional electrocatalysts for urea oxidation

Abstract

Organic-inorganic nanohybrids with nanoscale architectures and electrocatalytic properties are emerging as a new branch of advanced functional materials. Herein, nanohybrid organic-inorganic nanosheets are grown on carbon paper via pulsed-electrochemical deposition...

Coaxial Ni–S@N-Doped Carbon Nanofibers Derived Hierarchical Electrodes for Efficient H2 Production via Urea Electrolysis

“…We further compared the intrinsic activities of these catalyst toward urea oxidation by the plot of TOF versus potential, as shown in Figure S18. The TOF was about 0.258 s −1 for NF/PPy 700 -Ni 3 S 2 -8-Ar at 1.352 V, which not only is larger than the two control groups of NF/ N 3 S 2 −Ar (0.0005 s −1 ) and NF/PPy 700 -Ni 3 S 2 -8-H 2 (0.0017 s −1 ) but also outperformed previously published UOR electrocatalysts, such as NP-Ni 0.70 Fe 0.30 (0.0060 s −1 @1.45 V), 64 CFP-NiMn 1.4 (0.018 0 s −1 @1.45 V), 65 BSeFL/Ni(OH) 2 (0.0150 s −1 @1.4 V), 47 and MNPBA-P (0.1010 s −1 @1.344 V). 42 Meanwhile, in urea containing alkaline electrolyte solution, NF/PPy 700 -Ni 3 S 2 -8-Ar displays smaller R ct compared to the control groups, as shown in Figure 5g, confirming the electron transfer rate was faster than the other samples without a hierarchical conductive path or without metal active sites.…”

“…For further investigation on the electrocatalytic activity of the UOR, the turnover frequencies (TOFs) of all samples were calculated by the following eq where j is the current density of the LSV curves, z is the electron transfer number per molecule generated, F is the Faraday constant, and n is the number of active sites (for rational comparison, the mole of Ni 3 S 2 was used).…”

Coupling Interface Constructions of FeNi3-MoO2 Heterostructures for Efficient Urea Oxidation and Hydrogen Evolution Reaction

“…Furthermore, the metal content of catalysts is confirmed by inductively coupled plasma mass spectrometry (ICP-MS) (Table S2). Then the turnover frequency (TOF) is calculated assuming all metal ions in the samples are catalytic active, and the intrinsic activities of the catalysts are assessed by TOF. , As shown in Figure b, FeNi 3 -MoO 2 /NF exhibits a high TOF value of 0.023 s –1 at 1.4 V for UOR, which is superior to that of NiMoO 4 /NF (0.003 s –1 ), Ni-MoO 2 /NF (0.013 s –1 ), FeNi 3 /NF (0.015 s –1 ), and MoO 2 /NF (0.012 s –1 ), further proving the preeminent activity of the FeNi 3 -MoO 2 /NF.…”

Strategies for designing more efficient electrocatalysts towards the urea oxidation reaction

“…The production of urea in industries, and the use of urea as a nitrogen-release fertilizer in agriculture also result in the generation of urea-containing wastewater. 3–5 For example, production of every 1 kg urea in manufacturing plants contributes to 0.75 kg urea-containing wastewater, which has around 1 wt% urea. 6 Unfortunately, untreated urea-containing wastewater brings serious environmental problems.…”