Dynamic active sites on plasma engraved Ni hydroxide for enhanced electro-catalytic urea oxidation

Fluorinated Ni‐O‐C Heterogeneous Catalyst for Efficient Urea‐Assisted Hydrogen Production

“…[32] Generally, the higher drop in the phase angle indicates faster electron transfer process. [33] For NiO/Ni@C, the phase angle in the low-frequency region is stable in the potential range of 1.26 ≈ 1.34 V and exhibit sharp drop when the given potential is over 1.36 V. This is consistent with the tendency that is observed in the intermediatefrequency region, further revealing that UOR were commenced due to the accumulation of intermediates (Figure S27a, Supporting Information). [34] In sharp contrast, the phase angle for F-NiO/Ni@C drops drastically in the low-frequency region while remaining relatively stable in the mid-frequency region (1.26 ≈ 1.34 V).…”

Electrocatalytic urea oxidation: advances in mechanistic insights, nanocatalyst design, and applications

“…Inspired by the catalytic activity along with the number of active sites for nanocatalysts, a usual strategy for enhancing the UOR performance is to maximize the specic surface area and decrease the size via geometric engineering, such as nanosheets, 24,99,125 mesoporous structures, 25 small-size nanoparticles, 126 single atoms, 37,110,127 and so on. Recently, Liu et al showed that Ni 2 P nanosheets with a thickness of 130 nm exhibited a low onset potential of 1.33 V owing to the increased number of exposed catalytically active sites and accelerated ion diffusion of electrolyte.…”

“…7b). 125 The more accessible interlayer channels and unsaturated coordination atoms can obviously improve the UOR performance of Ni(OH) 2 , showing a potential of 0.343 V ( vs. Hg/HgO) to achieve a current density of 10 mA cm −2 .…”

Accelerating charge transfer for Ni(OH)2 through chlorine-anion decoration in the urea electrooxidation reaction

“…4e) showed a considerable enrichment of Ni 3+ , validating more NiOOH active sites. 37,38 Notably, in Fig. 4f, the XPS spectra of Cl 2p of Cl 32 -Ni(OH) 2 were not detected after the durability test which implies that the incorporated Cl À ions are likely to be leached out during the UOR process.…”