Liquid Fluxional Ga Single Atom Catalysts for Efficient Electrochemical CO₂Reduction

Abstract

Precise design and tuning of the micro-atomic structure of single atom catalysts (SACs) can help efficiently adapt complex catalytic systems. Herein, we inventively found that when the active center of the main group element gallium (Ga) is downsized to the atomic level, whose characteristic has significant differences from conventional bulk and rigid Ga catalysts. The Ga SACs with a P, S atomic coordination environment display specific flow properties, showing CO products with FE of � 92 % at À 0.3 V vs. RHE in electrochemical CO 2 reduction (CO 2 RR). Theoretical simulations demonstrate that the adaptive dynamic transition of Ga optimizes the adsorption energy of the *COOH intermediate and renews the active sites in time, leading to excellent CO 2 RR selectivity and stability. This liquid single atom catalysts system with dynamic interfaces lays the foundation for future exploration of synthesis and catalysis.

Rational design of atomic site catalysts for electrochemical CO2reduction

“…3). 34–36,45,54–69 Besides, the generated *CO may not be desorbed immediately, but further reduced as an intermediate to generate *CHO. Then, the *CHO intermediate can be converted to *CH 2 O by a PCET step and further reduced to CH 3 OH.…”

“…3). [34][35][36]45,[54][55][56][57][58][59][60][61][62][63][64][65][66][67][68][69] Besides, the generated *CO may not be 42,70,71 In addition, *CHO can also be hydrogenated to *CHOH rather than *CH 2 O, with four subsequent PCET steps to generate CH 4 . To date, Cu and Zn ASCs have been reported to show excellent potential for electrochemical CO 2 -to-CH 4 conversion.…”

Enhancing Heterogeneous Catalysis by Electronic Property Regulation of Single Atom Catalysts

“…On the one hand, the "bottom-up" approach begins with the mononuclear metal complexes and the core of this route is to reduce the metal loading and stabilize the metal atoms via strong EMSI (i.e., coordination stabilization) 29 . Three strategies are mainly used in "bottom-up" route: 1) coordination sites construction strategy: selecting supports with abundant coordination atoms like nitrogen, phosphorus, and sulfur atoms to tightly anchor the metal atoms 30 ; 2) spatial confinement strategy: porous materials containing ample coordination sites (N, P, S) in skeletons and uniform pores, e.g., zeolite, metalorganic frameworks (MOFs), and covalent-organic frameworks (COFs) are almost always served as hosts to evenly confine the metal atoms [31][32][33][34][35] ; 3) defects design strategy: the vacancies and unsaturated coordination sites generated from the defects of supports could be utilized to capture mononuclear metal complexes 36 . Reversely, metal nanoparticles or bulk metal are the starting precursors of "top-down" synthetic route 37,38 .…”

Highly selective CO2electroreduction to CO by the synergy between Ni–N–C and encapsulated Ni nanoparticles

“…Through the CO 2 RR performance test, they found that the Ga-N 3 S-PC catalyst differs from the traditional bulk gallium metal and Ga-N 4 catalysts which exhibits >90% FE of the CO product. 17 Ni et al designed an intrinsic defect-rich graphene-like porous carbon embedded with single-atom Fe-N 4 sites and found that it delivered excellent CO 2 -to-CO conversion performance in terms of FE CO (90%) and CO partial current density (33 mA cm −2 ) in 0.1 M KHCO 3 . 18 Besides, high-curvature carbon-supported Ni single atoms with charge polarization have also been demonstrated to improve the CO 2 RR performance.…”