Promoting biomass electrooxidation via modulating proton and oxygen anion deintercalation in hydroxide

Abstract

The redox center of transition metal oxides and hydroxides is generally considered to be the metal site. Interestingly, proton and oxygen in the lattice recently are found to be actively involved in the catalytic reactions, and critically determine the reactivity. Herein, taking glycerol electrooxidation reaction as the model reaction, we reveal systematically the impact of proton and oxygen anion (de)intercalation processes on the elementary steps. Combining density functional theory calculations and advanced spectroscopy techniques, we find that doping Co into Ni-hydroxide promotes the deintercalation of proton and oxygen anion from the catalyst surface. The oxygen vacancies formed in NiCo hydroxide during glycerol electrooxidation reaction increase d-band filling on Co sites, facilitating the charge transfer from catalyst surface to cleaved molecules during the 2nd C-C bond cleavage. Consequently, NiCo hydroxide exhibits enhanced glycerol electrooxidation activity, with a current density of 100 mA/cm2 at 1.35 V and a formate selectivity of 94.3%.

Facile surface reconstructions of cobalt–copper phosphide heterostructures enable efficient electrocatalytic glycerol oxidation for energy-saving hydrogen evolution

“…31,32 The most effective electrocatalysts for the GOR reported so far are often based on noble metals 33 such as Au, Pd, Pt and their alloys (PtBi and PdBi), 34,35 which suffer from high cost and poor stability against poisoning, making them less competitive for economically feasible hydrogen production. In recent reports, transition metal-based catalysts have shown great promise as alternatives to noble metals for the GOR in alkaline media, including transition metal oxides, [36][37][38][39] hydroxides, [40][41][42][43][44] and nitrides. 12,45,46 In particular, metal oxides and hydroxides containing both Co and Cu have demonstrated good activity toward the GOR.…”

Co-generation of electricity and formate in glycerol fuel cells with a bifunctional PdPtAg alloy nanowire electrocatalyst

“…[1][2][3] With the increase of global biodiesel production (average annual growth rate of 4.1% over the last decade), efficient utilization of glycerol is urgent and profitable. [4][5][6][7][8] Nowadays, the main way of utilizing glycerol is the catalytic oxidation of glycerol to value-added chemicals used in food, pharmaceutical, and cosmetics industries, such as 1,3-dihydroxyacetone (DHA), glyceric acid, and glyceraldehyde. But the market sizes of these fine chemicals produced via glycerol oxidation are likely too small to make a meaningful impact on global glycerol consumption.…”

“…45 These factors jointly make Ag NWs the best matrix for the incorporation of Pt and Pd atoms. (5) From the perspective of economy, the alloying strategy can reduce the usage of Pd and Pt and is ultimately conducive to the reduction of the operation cost of the DGFC, as Ag is more abundant and much cheaper than Pt and Pd.…”

Modulating O–H Activation of Methanol Oxidation on Nickel-Organic Frameworks for Overall CO2 Electrolysis

“…1.35 V vs RHE). This phenomenon indicates that the electrophilic OOH* could be consumed by nucleophilic methanol molecules via a dehydration process, which further proves that Ni-OOH is the real catalytic site. , Hence, Ni-OOH would not accumulate on the catalyst surface during MOR, and the formation of Ni-OOH is the rate-determining step for Ni-MOFs@350 to catalyze methanol refinery at working potentials less than 1.8 V vs RHE . The promoted in situ generation of the Ni-OOH phase within Ni-MOFs@350 is confirmed in comparison with Ni-MOFs and Ni-MOFs@400 (Figure S20).…”