Alcohol oxidation with high efficiency and selectivity by nickel phosphide phases

Abstract

Small aliphatic alcohols are excellent fuels that have a much higher energy density than liquid H2. It is advantageous to avoid their complete oxidation to CO2 and produce chemicals with...

Integrating Electrochemical CO2 Reduction on α-NiS with the Water or Organic Oxidations by Its Electro-Oxidized NiO(OH) Counterpart to an Artificial Photosynthetic Scheme

“…In this context, the choice of the redox mediator plays a pivotal role. In practice, the transition-metal catalysts and their oxy-hydroxide phases are proven to be highly active for the organic electro-oxidation. ,,, Notable performance was observed with the Ni-based material as the mediator such as Ni 3 S 2 and Ni 12 P 5 where the NiO­(OH) is proposed to be the true redox mediator . Given that, in situ-derived NiO­(OH) ED would be an obvious choice to explore the electro-conversion of organic feedstocks like HMF, EG, FF, and Gly.…”

“…By analogy to the literature proposals on these, the formation of formate could only be possible through oxidation of one of the terminals −CH 2 –OH to aldehyde and further to carboxylate, as the initial steps. In the subsequent steps, carboxylate may undergo a C–C bond cleavage reaction to formate . However, oxidation of EG to oxalate would also be possible, which may further oxidize to end up with CO 2 .…”

“…However, herein, the NiO­(OH) ED selectively oxidized EG and Gly to formate. Notably, the recently reported nickel-based electrocatalysts show poor selectivity toward formate production from Gly . In that context, some reports on noble metals like Pt and Au have showcased that they either are ineffective toward C–C bond cleavage or require very high oxidative potentials …”

Origin of the Universal Potential-Dependent Organic Oxidation on Nickel Oxyhydroxide

“…10−20 This route can not only replace the low-valued oxygen product with the value-added carboxylic acid or nitrile products but also require lower energy cost due to the higher reactivities of the organics, which together decrease the composite cost of hydrogen. 12,17,21 Nickel oxyhydroxide (NiO x (OH) 2−x , x = 1− 2 depending on the oxidation state of Ni and phase structure of the pristine Ni(OH) 2 ) is one of the most active catalysts toward the electrochemical selective oxidation of these organics. 10−14,18,20,22−26 Its low cost, facile accessibility, scalable production, and widespread use in industrial alkaline electrolyzers have promoted the research focus as the potential electrocatalyst candidate.…”

Ru-doping induced lattice strain in hetero-phase Ni2P–Ni12P5arrays enables simultaneous efficient energy-saving hydrogen generation and formate electrosynthesis

“…phosphides have attracted much attention due to their abundant resources, low cost, and comparable catalytic performance to noble metal materials. [19][20][21][22][23][24] To boost the catalytic performance of metal phosphides, tremendous research efforts have been devoted to surface microstructure tailoring and rational modulation of the electronic structure. Hetero-phase interface engineering of nanostructured catalysts can ne regulate the local electronic conguration of active sites on the heterophase interface, and thus trigger intriguing catalytic properties.…”