Structural Effectiveness of AgCl-decorated Ag Nanowires Enhancing Oxygen Reduction

Abstract

In anion exchange membrane fuel cells (AEMFCs) for green energy, silver (Ag)-based compounds are promising non-Pt electrocatalysts with high catalytic activity and a low cost for the oxygen reduction reaction (ORR). Although silver chloride (AgCl) shows high catalytic activity due to the ligand effect originating from the electronegativity difference between the two elements, its low electroconductivity remains a significant issue. Here, we report Ag-AgCl core–shell nanowires decorated with AgCl (AgCl-Ag@AgCl NWs) that have a structure capable of simultaneously exhibiting the good conductivity of a long silver (Ag) core and the high ORR catalytic activity of silver chloride (AgCl). In addition, by decorating AgCl nanoclusters on the AgCl shell, AgCl-Ag@AgCl NWs have an enlarged active surface. As a result, AgCl-Ag@AgCl NWs show highly improved catalytic performance (half-wave potential = 0.78 V vs a reversible hydrogen electrode (RHE), limiting current density = 4.51 mA/cm2). Accelerated durability tests (ADTs) confirm the high stability of AgCl-Ag@AgCl NWs after 4000 cycles of potential sweep and rotating ring disk electrode (RRDE) analysis shows remarkable efficiency with the high electron transfer number (n) (3.97). We also use density functional theory (DFT) calculation to confirm charge transfer, which improves the activity of our catalysts.

Hollow Molybdate Microspheres as Catalytic Hosts for Enhancing the Electrochemical Performance of Sulfur Cathode under High Sulfur Loading and Lean Electrolyte

“…The immersed CMO, NMO, and MMO powders are thoroughly dried for the XPS testing, and compared with the pristine samples. Mo in the pristine molybdate oxides resides in the oxidation state of Mo (VI) with a pair of Mo 3d 5/2 (232.31–232.63 eV) and Mo 3d 3/2 peaks, [ 45–47 ] with a slight difference in binding energy due to the discrepancies of surficial element compositions (Figure 4c–e). And Co, Ni, and Mn are all divalent (Figure S8, Supporting Information).…”

Ag/AgCl clusters derived from AgCu alloy nanoparticles as electrocatalysts for the oxygen reduction reaction

“…26 Choi et al also presented that the conductivity of AgCl could be improved by using Ag nanowires as a core structure which had a positive impact on the catalytic activity. 27 Herein, we report a superior ORR activity of the Ag/AgCl nanostructures derived from the selective dealloying of AgCu alloy NPs in the acidic solution. It was found that the nal structural phase that exhibited the best ORR activity depended strongly on initial AgCu alloy compositions and Cu dealloying process parameters, indicating that multiple steps must be followed.…”

“…26 Choi et al also presented that the conductivity of AgCl could be improved by using Ag nanowires as a core structure which had a positive impact on the catalytic activity. 27…”

Formulating electronic descriptors to rationally design graphene-supported single-atom catalysts for oxygen electrocatalysis

“…Therefore, several approaches have been proposed to reduce the usage of precious PGMs while maintaining high catalytic performance. [5][6][7][8][9][10][11][12] Recently, graphenesupported single-atom catalysts (G-SACs) have been demonstrated to be one of the best of these strategies because G-SACs not only decrease the amount of loaded precious metal but also improve the mass activity by maximizing the atomic efficiency with high product selectivity. 2,3,13,14 However, G-SACs always face stability issues owing to the high chemical potential of single atoms, particularly agglomeration and dissolution.…”