Unveiling the effect of shapes and electrolytes on the electrocatalytic ethanol oxidation activity of self-standing Pd nanostructures

Unravelling the Alloy Effect of Porous Binary Pd-Based Nanostructures on Electrocatalytic Oxidation of Carbon Monoxide in Different Electrolytes

“…The Pd 3d spectra in the PdM nanostructures deconvoluted into Pd 3d 5/2 and Pd 3d 3/2 as the main metallic phase (Pd 0 ) and minor phase as Pd 2+ (Figure c–e). Unlike PdCu and PdMn with distinct Pd 3d 5/2 and Pd 3d 3/2 , AuPd showed only a broad peak of Pd 3d 5/2 and small peak for Pd3d 3/2 , plausibly due to the great synergism between Pd and Au and strong electronic interaction, as reported before . Nevertheless, the ratio of Pd o to Pd 2+ in PdCu (1.3) was lower than that in PdMn (1.8) and AuPd (2.8).…”

“…Au 4f spectra were fitted into the metallic phase (Au 0 4f 7/2 and Au 0 4f 5/2 ) and Au-oxide phases (i.e., Au 1+ and Au 3+ ) (Figure h). The co-existence of M-oxide phases (Pd 2+ , Cu 2+ , Mn 2+ , Au 1+ , and Au 3+ ) is beneficent for the enhancement of the adsorption of reactants along with accelerating the dissociation of H 2 O to generate the active oxygenated species that can endow the CO oxidation at lower applied potential. ,, …”

“…8°), resulting in the lower crystallite size of PdCu (4.3 nm) relative to AuPd (7.20 nm) and PdMn (6.6 nm), according to the Scherrer equation using approximation spherical crystallites shape factor (K = 0.89). This is further seen in the dissimilar lattice parameter (a) of PdCu (2.229 Å), PdMn (2.249 Å), and AuPd (2.297 Å) compared with pure Pd nanoparticle (2.246 Å).40,45,46 Moreover, the lattice constants of PdCu (3.8610 Å), AuPd (3.979 Å), and PdMn (3.895 Å) are dissimilar to that of pure Pd (3.891 Å). The positive shift in the Pd{111} peak is a sign of increased Pd−Pd interatomic distance resulting from the lattice contraction, which leads to a decreased value, so the lattice in PdCu should be higher than that of PdMn and AuPd.…”

Interfacial Engineering of Porous Pd/M (M = Au, Cu, Mn) Sponge-like Nanocrystals with a Clean Surface for Enhanced Alkaline Electrochemical Oxidation of Ethanol

“…Pd-based catalysts are eminent with their superior EOR activity and less susceptible to poisoning by carbonaceous species; − however, their intolerable cost and earth-rarity are critical barriers. − Also, the difficult cleavage of the C–C bond into CO ad and CH ad , besides ease of C–O bond coupling on Pd, which forms acetaldehyde or acetic acid as the preferred product(s), decreases the faradaic efficiency of practical AEFCs. − Potential solutions culminated in tailoring the size and morphology of Pd using supports (i.e., carbon and graphene) and alloying with less expensive and earth-abundant metals (i.e., Cu, Mo, Fe, Mn, Co etc. ). − The latter one is the most promising for promoting EOR performance and reducing consumption of Pd.…”

Controlling the Synthesis Protocols of Palladium‐Based Nanostructures for Enhanced Electrocatalytic Oxidation of Carbon Monoxide: A Mini‐Review

“…The CO Oxid is usually achieved by thermal, electrochemical, and photoelectrochemical methods in the presence of various catalysts (i. e., noble metals, transition metals, and quantum dots) [1–3] . Although the thermal process is the most common in the industry, its high energy demand (i. e. heating to elevated temperature) is a great barrier, [4,5] whilst the electrochemical CO Oxid is less energy demand (i. e., it occurs at room temperature and atmospheric pressure) and meets the sustainability requirements [6–8] . Unlike other electrocatalysts (i. e., PtRu, PtSn, Pt/metal oxide, and Rh N 4 ), Pd‐based catalysts have better tolerance to CO poisoning, particularly in alkaline conditions [9,10] .…”