Construction of a hierarchically structured, NiCo–Cu-based trifunctional electrocatalyst for efficient overall water splitting and 5-hydroxymethylfurfural oxidation

Abstract

In this study, Cu nanowire arrays grown on a three-dimensional Cu foam substrate are modified by nickel-cobalt layered double hydroxide nanosheets (NiCoNSs/CuNWs), which can be used as a self-supporting trifunctional...

Electrochemical Hydrogen Generation by Oxygen Evolution Reaction‐Alternative Anodic Oxidation Reactions

“…The MoO 2 –FeP@C||MoO 2 –FeP@C electrolyzer afforded a voltage of 1.486 V at 10 mA cm −2 for simultaneously generation of FDCA H 2 . [ 28 ] Other catalysts such as NiSe@NiO x core–shell nanowires, [ 62 ] Mo‐doped Ni 0.85 Se on nickel foam (NF@Mo–Ni 0.85 Se), [ 31 ] Cu x S@NiCo‐LDHs core–shell nanoarray, [ 61 ] and nickel‐cobalt‐layered double‐hydroxide NSs modifying Cu nanowire arrays on Cu foam (NiCo NSs /Cu NWs ) [ 65 ] were also reported in the HMF electrolysis system which shows desirable catalytic performance ( Table 4 ).…”

Alloy‐Driven Efficient Electrocatalytic Oxidation of Biomass‐Derived 5‐Hydroxymethylfurfural towards 2,5‐Furandicarboxylic Acid: A Review

“…For example, Ni generally offers high currents, while Co lowers the onset potential (usually the onset potential of precious metals is also very low) [62] . Consequently, NiCo alloys achieve low onset potentials and large catalytic currents, thus boosting the oxidation efficiency of HMF [63] . Apart from that, many studies have revealed that Au catalysts are more efficient for the oxidation of aldehyde groups with desirable selectivity, but Au may be deactivated more easily by the formed organic products [64] .…”

“…[62] Consequently, NiCo alloys achieve low onset potentials and large catalytic currents, thus boosting the oxidation efficiency of HMF. [63] Apart from that, many studies have revealed that Au catalysts are more efficient for the oxidation of aldehyde groups with desirable selectivity, but Au may be deactivated more easily by the formed organic products. [64] Instead, Pt and Pd catalysts are more efficient for the oxidation of alcohol groups, and they can keep Au stable.…”

“…By introducing Co 2 + , the unpaired electrons in the π-symmetry (t 2g ) d-orbital could interact with O 2À , weakening the e À -e À repulsion and prompting the partial charge transfer from Ni 2 + to Co 2 + and then formed a high valent nickel species, which was the real active substance that catalyzed the oxidation of HMF functional groups, resulting in a better HMF catalytic oxidation. Similarly, Zheng et al [63] used NiCo alloys, which were modified with Cu nanowire arrays grown on three-dimensional (3D) Cu foam substrates, to prepare self-supported trifunctional electrocatalysts for the electrocatalytic HMF oxidation. The budget electrocatalysts were of a high conductivity and could not only be used for the Table 1.…”

Aufwertung organischer Verbindungen durch Kopplung von Elektrooxidation und Wasserstoffentwicklung

“…[71] Sun et al integrierten die HMF-Umwandlung und H 2 -Entwicklung in 1.0 M KOH auf bifunktio-nalen Elektrokatalysatoren, wie CoP, [50] Ni 2 P [55] und Ni 3 S 2 , [56] wodurch die Produktion von FDCA und H 2 mit hohen FEs realisiert wurde. Andere bifunktionale Elektrokatalysatoren, wie Co-NW/NF, [72] MoO 2 -FeP@C, [61] NiSe@NiO x -NWs, [73] Cu x S@NiCo-LDHs, [74] NF@Mo-Ni 0.85 Se, [75] NiCo-LDH NiCo NSs/ Cu NWs [76] und Ni 3 N@C, [45] wurden ebenfalls für die Hybridelektrokatalyse beschrieben. Bei den oben stellvertretend genannten Elektrokatalysatoren folgen die Alkohol-und Aldehydumwandlungen in der Regel dem intramolekularen Mechanismus der Elektrooxidation in alkalischen Medien, bei dem eine starke Wechselwirkung zwischen dem organischen Substrat und der Elektrodenoberfläche besteht.…”