Cyanogel‐Induced PdCu Alloy with Pd‐Enriched Surface for Formic Acid Oxidation and Oxygen Reduction

Abstract

Pd‐based catalysts with preferred morphologies and compositions are of great significance for boosting oxygen reduction reaction (ORR) and formic acid oxidation reaction (FAOR) performance, but the development of facile preparation methods is challenging. Therefore, an unconventional strategy is proposed to synthesize palladium‐copper cyanogel (Cux[Pd(CN)4]y·aH2O) and subsequently induce the formation of PdCu alloy nanocorals (ANCs), which has the advantages of being simple, green, and efficient. The synthesized PdCu ANCs consist of a 3D porous network structure and Pd‐enriched surface, which is beneficial to exposing more accessible active sites, accelerating mass/electron transfer rate, and strengthening chemical stability. By virtue of these merits, the PdCu ANCs exhibit superior activity and stability in both FAOR and ORR. Remarkably, the mass activity of PdCu ANCs catalyst in FAOR reaches 554.53 mA mgPd−1, with a 4.8‐fold enhancement compared to commercial Pd black. And the half‐wave potential of 0.861 V of PdCu ANCs catalyst in ORR surpasses the values of commercial Pd black and Pt black catalysts.

Spin‐Selective Coupling in Mott–Schottky Er2O3‐Co Boosts Electrocatalytic Oxygen Reduction

“…It is known that a small Tafel slope reflects accelerated ORR reaction kinetics. [ 49,50 ] As indicated in Figure 3d, the Tafel slope is 76 mV dec −1 for Er 2 O 3 ‐Co/CNF which outperforms that of Co/CNF (81 mV dec −1 ) and Er 2 O 3 /CNF (162 mV dec −1 ) and is close to Pt/C (70 mV dec −1 ), suggesting the facilitated ORR kinetics with the synergism between Er 2 O 3 and Co species. The Koutecky–Levich (K‐L) plots originated from LSV curves at different rotating speeds show good linear parallelism (Figure S12, Supporting Information), indicating a first‐order reaction.…”

Electrochemical synthesis of dendritic Pd-CoO/PW10V2/rGO and its electrocatalytic performance for formic acid oxidation

“…Meanwhile, the peaks at 337.8 eV and 342.5 eV are ascribed to Pd 4+ . 42,43 The relative area of Pd 0 , Pd 2+ and Pd 4+ is 73.18%, 17.39% and 9.43%, respectively, manifesting that Pd mainly exists in the Pd 0 form in the composite. For the Co2p spectrum (Fig.…”

Neodymium‐Evoked Valence Electronic Modulation to Balance Reversible Oxygen Electrocatalysis

“…plots, the n of Nd/Co@NC was counted to be ≈3.8, which is close to the theoretical value (4.0), demonstrating that the 4e − ORR pathway occurred on the surface of Nd/Co@NC. [47] Apart from excellent ORR activity, Nd/Co@NC also exhibits superior stability for the ORR. Figure 5e shows the i-t curves of catalysts in O 2 -saturated 0.1 M KOH solution at 0.5 V. After continuous operation for 12 h, the retention of current density for Nd/Co@NC (94.5%) is noticeably higher than that of Co@ NC (85.7%) and commercial Pt/C (74.3%).…”