Engineering Under‐Coordinated Active Sites with Tailored Chemical Microenvironments over Mosaic Bismuth Nanosheets for Selective CO₂ Electroreduction to Formate

Abstract

Selective electrochemical reduction of CO2 into fuels or chemical feedstocks is a promising avenue to achieve carbon‐neutral goal, but its development is severely limited by the lack of highly efficient electrocatalysts. Herein, cation‐exchange strategy is combined with electrochemical self‐reconstruction strategy to successfully develop diethylenetriamine‐functionalized mosaic Bi nanosheets (mBi‐DETA NSs) for selective electrocatalytic CO2 reduction to formate, delivering a superior formate Faradaic efficiency of 96.87% at a low potential of −0.8 VRHE. Mosaic nanosheet morphology of Bi can sufficiently expose the under‐coordinated Bi active sites and promote the activation of CO2 molecules to form the OCHO−* intermediate. Moreover, in situ attenuated total reflectance infrared spectra further corroborate that surface chemical microenvironment modulation of mosaic Bi nanosheets via DETA functionalization can improve CO2 adsorption on the catalyst surface and stabilize the key intermediate (OCHO−*) due to the presence of amine groups, thus facilitate the CO2‐to‐HCOO− reaction kinetics and promote formate formation.

Sustainable Ammonia Electrosynthesis from Nitrate Wastewater Coupled to Electrocatalytic Upcycling of Polyethylene Terephthalate Plastic Waste

“…To evaluate the intrinsic catalytic activity of the electrocatalyst, the electrochemically active surface area (ECSA), which represents the number of exposed active sites of the electrocatalyst, was measured by using the double layer capacitance (C dl ). , Figure S23a and S23b displays the CV curves of Co­(OH) 2 /NF and Ru-Co­(OH) 2 /NF at a series of scan rates. The fitting curves of the capacitive currents and the scan rates can obtain a C dl of 6.88 mF cm –2 on Ru-Co­(OH) 2 /NF and a C dl of 2.32 mF cm –2 on Co­(OH) 2 /NF, respectively, indicating that Ru-Co­(OH) 2 /NF (ECSA: C dl /0.04 mF cm –2 per cm 2 ECSA = 172 cm 2 ) possesses a larger ECSA than Co­(OH)/NF (ECSA: 58 cm 2 , Figure S23c).…”

Controlled boron incorporation tuned two-phase interfaces and Lewis acid sites in bismuth nanosheets for driving CO2 electroreduction to formate

“…44-1246). 45–48 Upon introducing B (Bi/B atomic ratio = 54/46, a/c -BiB NAs/CF), the diffraction intensities of the characteristic peaks for Bi metal become weak and broad, which is attributed to the decrease in crystallinity compared with the initial c -Bi NAs/CF. With the increase of the amount of B introduced (Bi/B atomic ratio = 36/64, a -BiB NAs/CF), the nanosheet structure was completely transformed into amorphous, as revealed by the disappearance of Bi characteristic diffraction peaks.…”

Engineering metallenes for boosting electrocatalytic biomass-oxidation-assisted hydrogen evolution reaction

“…Surface modification by attaching functional molecules is also an effective approach to enhance the electrocatalytic HER performance of metallenes. [68][69][70][71] It was demonstrated that the chemical functionalization can effectively modify the electrode/electrolyte interface. [72][73][74] Moreover, surface chemical microenvironment engineering can also induce the electronic effect to not only facilitate the electron transfer but also optimize the binding strength with intermediates.…”