Universal Surfactant‐Free Strategy for Self‐Standing 3D Tremella‐Like Pd–M (M = Ag, Pb, and Au) Nanosheets for Superior Alcohols Electrocatalysis

Abstract

2000255 (1 of 9) Pd-based nanosheet materials have emerged as efficient catalysts for monobasic and polyhydric alcohol oxidation reactions. However, most reported synthetic methods of Pd-based nanosheets (NSs) are nonuniversal and surfactant-involved, leading to residue-covered surfaces with drastically damaged electrocatalytic properties. Herein, a universal, surfactant-free, simple one-pot route is developed for the precise synthesis of a kind of novel self-standing Pd-M (M = Ag, Pb, Au, Ga, Cu, Pt, etc.) NSs with tremella-like superstructures are assembled using ultrathin two-dimensional (2D) NSs. Benefiting from the universal surfactant-free methods, the obtained Pd-M NSs exhibit clean surfaces and stable three-dimensional (3D) self-standing structures that overcome the difficulty of normal close packing and overlapping 2D NSs. The Pd-M (M = Ag, Pb, and Au) NSs with tremella-like structures all show excellent ethanol oxidation reaction (EOR) and ethylene glycol oxidation reaction (EGOR) properties. In particular, with the optimal superstructure, better electronic effect, and promoted toxicity tolerance, the EOR/EGOR mass activities of Pd 7 Ag NSs, Pd 7 Pb NSs, and Pd 7 Au NSs are 8.2/7.3, 7.2/5.7, and 5.3/4.4 times higher than that of commercial Pd/C catalysts. This advanced 3D construction also endows Pd-M NSs with more favorable stability than Pd/C. This study may be extended to Pd-M (M = other metals) NSs and open up more opportunities for broad catalytic applications.

Recent Progress on Two-dimensional Electrocatalysis

“…In 2011, Zhang and his colleague [49] reported the synthesis of hexagonal close-packed(hcp) Au nanosheets with a thickness of only 2.4 nm, which provided a solid foundation for the development of Au in the electrocatalysis field. In addition to Pd and Au in 2D nanosheets structures, Pt, Ag and Ru have also been extensively studied in the 2D form for electrocatalysis [50][51][52][53] . However, these nanosheets are often obtained by galvanic replacement method.…”

Highly Active Hollow RhCu Nanoboxes toward Ethylene Glycol Electrooxidation

“…In general, the smaller DIA implies the smaller charge transfer resistance between the electrode and electrocatalyst and the higher reaction rate on the electrocatalyst surface. [28] Considering the unique structure of RhCu nanoboxes, the high ECSA and abundant pores should be responsible for the fast charge transfer. The tafel plots of the three electrocatalysts are derived from the linear region CV curves recorded at a low scan rate of 5 mV s −1 (Figure S7A, Supporting Information).…”

Platinum‐Based Electrocatalysts for Direct Alcohol Fuel Cells: Enhanced Performances toward Alcohol Oxidation Reactions

“…metal electrocatalysts, one of the most effective strategies to modify their electronic structure is to introduce the second or more metal elements into Pt matrix to form bimetallic or multimetallic nanocrystals. [46,[99][100][101][102][103] The d-band centre of Pt will be shifted because the mismatch arrangement of atoms in Ptbased bimetallic or multi-metallic catalysts results in lattice strain, including tensile strain and compressive stress. Generally, the induced metals with smaller atomic radius can produce compressed surface strain and weaken the binding between Pt and the intermediate oxides which therefore improves the activity toward AOR.…”