Pd‐Based Metallenes for Fuel Cell Reactions

Abstract

Pd-based metallenes, atomically thin layers composed primarily of under-coordinated Pd atoms, have emerged as the newest members in the family of two-dimensional (2D) nanomaterials. Moreover, the unique physiochemical properties, high intrinsic activity associated with metallenes coupled with the ease of applying chemical modifications result in great potential in catalyst engineering for fuel cell reactions. Especially in recent years, interest in Pd-based metallenes is growing, as evidenced by surge in available literatures. Herein, we have reviewed the recent findings achieved in Pd-based metallenes in fuel cells by highlighting the technologies available for deriving metallenes and manifesting the modification strategies for designing them to better suit the application demand. Moreover, we also discuss the perspective insights of Pdbased metallenes for fuel cells regarding the surfactant-free synthesis method, strain engineering, constructing high-entropy alloy, and so on.

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

“…Alloying noble metals with other non-noble metals is widely considered as a promising strategy for modifying the electronic structure of catalysts to optimize the binding strength with intermediates. [35][36][37][38] Pd metallenes have been firstly developed for boosting electrocatalytic reactions. However, systematical electrochemical measurements and theoretical analyses have uncovered that the intrinsic electronic structure of Pd is unfavorable for the electrocatalytic oxygen reduction reaction (ORR), which thus calls for the development of effective modification strategies.…”

Nanostructure engineering of Pt/Pd-based oxygen reduction reaction electrocatalysts

“…In addition to the synthesis of 2D hexagonal nanoplates, 2D Pd-based metallenes are also reported to be promising candidates for driving the ORR. [109][110][111][112][113][114][115][116][117] Luo et al demonstrated that PdMo metallenes can exhibit outstanding electrocatalytic ORR performance (Fig. 11a-c).…”

Engineering defective trimetallic metal–organic framework nanosheets for advanced water oxidation electrocatalysis

“…[8][9][10] However, with sluggish kinetics due to the multistep proton-coupled electron transfer, the anode oxygen evolution reaction (OER) of water electrolysis significantly limits the hydrogen production efficiency and rate. 11,12 To improve the OER kinetics and accelerate the reaction rate, introducing appropriate electrocatalysts is a practicable approach. For anodic OER, the state-of-the-art electrocatalysts are Ir/Ru oxides, but their rarity and high costs cannot satisfy scaled-up application yet.…”