CoSe₂ supported single Pt site catalysts for hydrogen peroxide generation via two‐electron oxygen reduction

Abstract

Electrocatalytic oxygen reduction reaction (ORR) to prepare H 2 O 2 in acidic medium has the advantages of green, safety, and portability, which shows broad development prospects. However, it still suffers from low catalyst activity, insufficient selectivity, and high cost. Herein, Pt 1 /CoSe 2 with ultralow 0.01 wt.% Pt atomic distribution was synthesized by a simple hydrothermal method. The Pt 1 /CoSe 2 with ultralow Pt content exhibits high activity, high selectivity, and long-term stability for ORR to H 2 O 2 in O 2 -saturated 0.1 M HClO 4 . The onset potential is as low as 0.75 V versus reversible hydrogen electrode (RHE), H 2 O 2 selectivity is as high as 84% (0.4 V vs. RHE), and the electron transfer number is 2.3 (0.4 V vs. RHE). Moreover, the hydrogen peroxide yield using the flow cell testing is 110.02 mmol g cat.−1 h −1 with high Faradaic efficiency of 78% (0 V vs. RHE) at 0.1 M HClO 4 , and the catalyst did not deactivate significantly after 60 h stability testing. Mechanistic studies and in situ X-ray photoelectron spectroscopy characterization confirm that the ultralow Pt content on CoSe 2 can effectively regulate the electronic structure of Co as the real active site around the Pt site, which gives a suitable ∆ dp value (the difference between the d-band center of the active metal site and the p-band center of the terminal oxygen in *OOH), provides an ideal *OOH binding energy, and inhibits the O-O bond breakage. This work successfully improves the intrinsic activity of the Co active sites around Pt in Pt 1 /CoSe 2 for acidic ORR to H 2 O 2 by constructing ultralow-content Pt single atom.

Artificial Phages with Biocatalytic Spikes for Synergistically Eradicating Antibiotic‐Resistant Biofilms

“…As revealed in Figure 2k; and Figure S10, and Table S2, Supporting Information, the primary peak signals of Co 2p are recognized as Co 2+ and Co 3+ , respectively. [43][44][45] Concurrently, the Co 2+ /Co 3+ intensity ratio in Ir@Co 3 O 4 (S) is 0.466, which is much smaller than pristine Co 3 O 4 (0.940). Taken together, we deduce that there are distinct, robust interactions and substantial electron transfer between Ir clusters and Co 3 O 4 , thereby enabling the stable anchor of Ir clusters.…”

Construction of Pt Single-Atom and Cluster/FeOOH Synergistic Active Sites for Efficient Electrocatalytic Hydrogen Evolution Reaction

“…The hydrogen evolution reaction (HER) as a half-reaction of water splitting has made great progress in the design of catalysts and the understanding of catalytic active sites in recent years. − In particular, Pt catalysts exhibit high-efficiency HER performance, but the high cost and scarcity of noble metals severely limit their applications. − Single-atom and cluster catalysts have attracted increasing attention due to their high atomic utilization and high intrinsic activity. − Lu et al found that the isolated Pt atoms on graphdiyne have high HER activity due to the high total unoccupied density of states of Pt 5d orbitals and close to zero of Gibbs free energy of the hydrogen adsorption . Wang et al reported a Pt single-atom anchoring on layered double hydroxide (LDH), where the interlayer Pt single-atom vastly enhanced the electron transferability of LDH support, providing high HER performance .…”