Modulating Pt-O-Pt atomic clusters with isolated cobalt atoms for enhanced hydrogen evolution catalysis

Abstract

Platinum is the most efficient catalyst for hydrogen evolution reaction in acidic conditions, but its widespread use has been impeded by scarcity and high cost. Herein, Pt atomic clusters (Pt ACs) containing Pt-O-Pt units were prepared using Co/N co-doped carbon (CoNC) as support. Pt ACs are anchored to single Co atoms on CoNC by forming strong interactions. Pt-ACs/CoNC exhibits only 24 mV overpotential at 10 mA cm−2 and a high mass activity of 28.6 A mg−1 at 50 mV, which is more than 6 times higher than commercial Pt/C with any Pt loadings. Spectroscopic measurements and computational modeling reveal the enhanced hydrogen generation activity attributes to the charge redistribution between Pt and O atoms in Pt-O-Pt units, making Pt atoms the main active sites and O linkers the assistants, thus optimizing the proton adsorption and hydrogen desorption. This work opens an avenue to fabricate noble-metal-based ACs stabilized by single-atom catalysts with desired properties for electrocatalysis.

Iridium single atoms incorporated in Co3O4 efficiently catalyze the oxygen evolution in acidic conditions

“…4d , the charge density difference on Ir-Co 3 O 4 indicates that the incorporation of Ir into Co 3 O 4 can effectively regulate the charge redistribution, where the Ir atom tends to lose electrons and the delocalized electrons accumulate around adjacent Ir-O bonds. This result also confirms a strong electronic interaction between the Ir single site and the host Co 3 O 4 67 . In addition, as shown in Fig.…”

A General Strategy to Remove Metal Aggregates toward Metal–Nitrogen–Carbon Catalysts with Exclusive Atomic Dispersion

“…Figure 2g presents the Pt L 3 ‐edge XANES curves, where the white‐line intensities of Pt‐SA/NP–NC and Pt‐SA–NC are between those of Pt foil and PtO 2 , suggesting that the average oxidation state of Pt is between 0 to +4 in both samples. [ 36 ] Careful observation reveals that the white‐line intensity of Pt‐SA/NP–NC is lower than that of Pt‐SA–NC, indicating a lower oxidation state of Pt in Pt‐SA/NP–NC due to the presence of metallic Pt species. As shown in the EXAFS Fourier transform (EXAFS‐FT) curves (Figure 2h), a major peak assigned to the PtN bond at ≈ 1.55 Å was observed in both Pt‐SA/NP–NC and Pt‐SANC.…”

Cobalt–platinum intermetallic composite loaded on pyridinic N-enriched carbon for acidic hydrogen evolution catalysis with ultralow overpotential

“…HER performance tests in 0.5 M H 2 SO 4 solution and 1.0 M KOH (degassed with N 2 ) 21 were conducted in a three-electrode configuration by using the Auto Lab electrochemical workstation (Metrohm, Multi Autolan m204). First, to prepare the catalyst ink, 10 mg of catalyst powder, 100 μL of Nafion (5 wt%), and 900 μL of isopropyl alcohol were ultrasonically mixed to get an evenly dispersed slurry.…”