Highly Efficient Electrocatalytic Upgrade of n-Valeraldehyde to Octane over Au SACs-NiMn2 O4 Spinel Synergetic Composites

Molybdenum iron carbide-copper hybrid as efficient electrooxidation catalyst for oxygen evolution reaction and synthesis of cinnamaldehyde/benzalacetone

Oxygen evolution reaction (OER) is the efficiency limiting half-reaction in water electrolysis for green hydrogen production due to the 4-electron multistep process with sluggish kinetics. The electrooxidation of thermodynamically more favorable organics accompanied by CC coupling is a promising way to synthesize value-added chemicals instead of OER. Efficient catalyst is of paramount importance to fulfill such a goal. Herein, a molybdenum iron carbide-copper hybrid (Mo2C-FeCu) was designed as anodic catalyst, which demonstrated decent OER catalytic capability with low overpotential of 238 mV at response current density of 10 mA cm-2 and fine stability. More importantly, the Mo2C-FeCu enabled electrooxidation assisted aldol condensation of phenylcarbinol with α-H containing alcohol/ketone in weak alkali electrolyte to selective synthesize cinnamaldehyde/benzalacetone at reduced potential. The hydroxyl and superoxide intermediate radicals generated at high potential are deemed to be responsible for the electrooxidation of phenylcarbinol and aldol condensation reactions to afford cinnamaldehyde/benzalacetone. The current work showcases an electrochemical-chemical combined CC coupling reaction to prepare organic chemicals, we believe more widespread organics can be synthesized by tailored electrochemical reactions.

Waste to treasure: Electrocatalytic upcycling of n-valeraldehyde to octane by Zn-Co bimetallic oxide with atomic level cation defect

n-Valeraldehyde is widely used in organic synthesis field as an important intermediate and feedstock, which makes it a significant class of environmental pollutants. In view of the high poisonous and harmful of n-valeraldehyde to human health and ecological environment, it is important to develop green and sustainable technology to reduce the pollution of n-valeraldehyde. In this work, electrocatalytic n-valeraldehyde oxidation using Zn-Co bimetallic oxides was applied to control n-valeraldehyde contamination and highly valuable octane production. To further improve the performance of Zn-Co bimetallic oxides, atomic level Zn vacancies were created across the Zn-Co bimetallic oxides (dx-ZnCo2O4) by post-etching and oxygen vacancy filling methods. Electrochemical experiments results showed that dx-ZnCo2O4 owned a much higher octane yield (1193.4 µmol g-1 h-1) and octane selectivity (octane/butene ≈10). Theoretical calculations demonstrated that the introduction of atomic level Zn vacancies in Zn-Co bimetallic oxide changed the electronic distribution around O, Co and Zn atoms, resulted in an alteration in n-valeraldehyde adsorption sites from Co to Zn, reduced the formation barrier of key intermediate *C4H9 and facilitated the transfer of n-valeraldehyde to octane. This study provides a new idea for the development of high-performance electrocatalysts for controlling n-valeraldehyde pollution.