Nanostructured electrocatalysts for electrochemical carboxylation with CO₂

Abstract

Electrocarboxylation of organic compounds with CO2, using electrons as clean reductants under ambient conditions, is a readily available and efficient method to transform organic molecules to high‐value carboxylates with nearly 100% atom efficiency. However, the selectivity of the electrochemical reactions is still limited, the real reactive sites for electrocarboxylation; the relationship between the geometrical/electronic structure and the catalytic performance is unclear. Meanwhile, the development of nanomaterials brings new prospects and orientation for the electrocarboxylation due to the desired high surface area and abundant active sites. In this review, we focus on the summary of recent work on the design of nanostructured electrocatalysts and the reaction mechanisms of electrocarboxylation. Mainly, we highlight the influence of different electrocatalyst structures on a variety of organic molecule adsorption. Finally, some challenges were proposed to explore advanced electrocatalysts and the deeper reactive mechanism for electrocarboxylation.

Design of flexible multi‐level topography for enhancing mechanical property

“…Nano‐materials with unique physical and chemical properties have received considerable attention in recent decades. [ 1–7 ] Its stability and duration are the most significant to design interfacial materials and micro‐electro‐mechanical systems, including superhydrophobicity, icephobicity, self‐cleaning, soft electronic circuits, and sensing systems. [ 8–14 ] However, the nano‐materials are always be ruined due to the base with weak mechanical properties.…”

Electrocatalytic Reactions for Converting CO2 to Value‐Added Products

“…Therefore, the electrocatalytic CO 2 reduction reaction (CO 2 RR) and coupling with small molecules or organic substrates have been greatly intriguing chemists and materials scientists in the past couple of decades. [8][9][10][11] Direct CO 2 RR has several potential products such as syngas, [12] methane, [13] formic acid, [14,15] ethanol, [16] and ethylene, [17] which can be used directly as fuels or further to produce chemicals. Different products can be obtained via CO 2 RR depending on the catalysts used.…”

“…•À ) can directly react with organic substrates such as olefins, alkynes, and carbonyl compounds into the carboxylic acid compound, known as the electrocarboxylation reaction. [11,25,26] Thus, it is economic and attractive to develop the coupled CO 2 RR with small molecules and organic substrates to obtain chemical raw materials. However, with the introduction of other reactants, four types of competing reactions can exist under the applied bias voltage, including hydrogen evolution reaction (HER), CO 2 RR, coupled CO 2 RR, and small molecules/organic substrates' reduction reaction.…”

Visible-light photoredox-catalyzed umpolung carboxylation of carbonyl compounds with CO2

“…First, it is highly challenging to avoid common side reactions, namely pinacol coupling 11 and hydrogen atom transfer (HAT) of ketyl radicals 60 . Second, as the direct radical addition of ketyl radicals to CO 2 is less favored 61 , 62 , a second SET reduction to generate a carbanion, which could attack electrophilic CO 2 , would be promising. However, the direct SET reduction of electron-rich ketyl radicals and/or ketyl radical anions is challenging.…”