In Situ Phase Separation into Coupled Interfaces for Promoting CO₂ Electroreduction to Formate over a Wide Potential Window

Abstract

Bimetallic sulfides are expected to realize efficient CO 2 electroreduction into formate over aw ide potential window,however,they will undergo in situ structural evolution under the reaction conditions.T herefore,c larifying the structural evolution process,t he real active site and the catalytic mechanism is significant. Here,taking Cu 2 SnS 3 as an example, we unveiled that Cu 2 SnS 3 occurred self-adapted phase separation towardf orming the stable SnO 2 @CuS and SnO 2 @Cu 2 O heterojunction during the electrochemical process.C alculations illustrated that the strongly coupled interfaces as real active sites driven the electron self-flow from Sn 4+ to Cu + , therebypromoting the delocalized Sn sites to combine HCOO* with H*. Cu 2 SnS 3 nanosheets achieve over 83.4 %f ormate selectivity in awide potential range from À0.6 VtoÀ1.1 V. Our findings provide insight into the structural evolution process and performance-enhanced origin of ternary sulfides under the CO 2 electroreduction.

In SituChalcogen Leaching Manipulates Reactant Interface toward Efficient Amine Electrooxidation

“…Electrifying high-value chemical manufacturing by the direct utilization of increasingly available renewable electricity provides an attractive route to advance the chemical industry, which is benefiting from multiple advantages, such as ensuring chemical valorization, reducing additional transportation costs, and negating the need for toxic reagents. − In particular, the anodic electrosynthesis process, such as electrochemical activation of C–H/N–H, urea oxidation, and biomass conversion, can be coupled with water splitting to produce high-purity hydrogen. − Due to the complex multielectron reaction process, these approaches usually require a high overpotential and are still far from industrial demand . Therefore, extensive efforts were made to optimize chemical interactions between reactive intermediates and the catalytic sites, , including our recent works on defect and interface engineering of 2D nanosheets. ,− From the perspective of electrochemical reaction kinetics, the overall performance is determined jointly by the energetic interaction and reactant interface. , Notably, the rapid migration and enrichment of reactive molecules in the vicinity of the catalyst surface are often the prerequisite for subsequent adsorption and multielectron reactions. , However, owing to the inherent inert catalyst surface and elusive electrochemical reactant interface, the understanding of and manipulating for mass order ( i . e ., spatial distribution/transport) may be extraordinarily insufficient relative to the common manipulation of electronic properties. , …”

Interface Molecular Functionalization of Cu2O for Synchronous Electrocatalytic Generation of Formate

“…The electrocatalytic conversion to generate valuable feedstocks such as the electrocatalytic reduction of carbon dioxide (CO 2 ) into liquid fuels is an emerging and fascinating pathway to alleviate the greenhouse effect and energy crisis. − The electrocatalytic CO 2 reduction reaction (ECRR) has attracted much attention because of the tunable products and the good compatibility with clean energy sources (e.g., solar energy). − Formate is an important chemical raw material and can also be used as the carrier of hydrogen (H 2 ) for fuel cells. , Metal electrocatalysts including Sn, In, and Bi are widely used to enhance the electrocatalytic efficiency for conversion of CO 2 into formate. − However, the catalytic performance of Cu-based electrocatalyts for the generation of formate still needs to be improved because of the moderate binding energy to the intermediates, resulting in low selectivity . In addition to regulate the bulk structure of Cu-based catalysts, − the interface composition and properties are crucial to improve catalytic performances. − The interface modifications can not only tune the electronic property of metal/metal oxide catalysts via covalent bonding but also adjust the binding energy of adsorbates via noncovalent interactions, thereby improving the ECRR selectivity. , Furthermore, the hydrophilic and hydrophobic properties of the catalyst can be regulated by interface modifications, which is the notable feature to determine the formation of formate or carbon monoxide (CO), respectively. , Besides, the interface modification can also preserve the surface structure of a catalyst and improve the stability of the catalytic efficiency …”

Engineering a Local Free Water Enriched Microenvironment for Surpassing Platinum Hydrogen Evolution Activity

“…[12] Consequently, the activation energies of water dissociation increased in the order: free 4a). [27] Besides, the electron states of the H 1s and O 2p orbitals downshifted further away from the Fermi level for interfacial OHÀ Ni/Ni 3 C than that of OHÀ Ni, which might suggest a stronger binding force of the former. [28] Electron localization function (ELF) evaluations were carried out to measure the excess kinetic energy density due to the Pauli repulsion (Figure 4b).…”