Engineering Pt and Fe dual-metal single atoms anchored on nitrogen-doped carbon with high activity and durability towards oxygen reduction reaction for zinc-air battery

Enhancement of Catalytic Activity and Durability of Pt Nanoparticle through Strong Chemical Interaction with Electrically Conductive Support of Magnéli Phase Titanium Oxide

“…On the other hand, both Pt/C samples have a 59.2, 18.8% of drop in MA, respectively. We also confirm that the Pt/MPTO samples in the literature show a nearly 50% reduction in ECSA and MA after 3k cycles [12]. We expected that the high durability of our Pt/MPTO sample compared to the literature is due to the improved SMSI effect by well-dispersion of Pt NPs on the MPTO with higher surface area.…”

“…To alleviate the negative effects of the amorphous carbon deterioration, corrosionresistant carbon supports; CNT [7,8], CNF [9], and graphene [10,11], heteroatom doped carbon [12] and also metal oxide supports have been introduced in the literature [13][14][15][16][17][18]. Among varied metal oxides [19][20][21], TiO 2 draws prominent attention because of high chemical-durability and good corrosion-resistance under PEFCs operation.…”

An Adjacent Atomic Platinum Site Enables Single‐Atom Iron with High Oxygen Reduction Reaction Performance

“…As observed in Figure 2 f, the Fe K ‐edge XANES profile (orange line) shows the edge energy ( E 0 ) value of Fe‐N 4 /Pt‐N 4 located between Fe foil and Fe 2 O 3 , confirming that the average oxidation state of Fe was positively charged below +3, consistent with the Fe 2p XPS result in Figure S19c. The Pt‐ L 3 edge adsorption fine structure in Figure 2 g shows that the Pt in the Fe‐N 4 /Pt‐N 4 is in the same oxidation state around +2, matching well with the previously reported literatures [19, 27b, 28] and Figure S19d. The coordination configurations were determined by the Fourier transformed (FT) EXAFS (Figure 2 h).…”

“…25° and ca. 43° in the XRD patterns could be well ascribed to (002) and (101) facets of the pyrolyzed graphitic carbon, [1b, 6h, 19, 27] respectively, which was further confirmed by the G‐band peaks at ca. 1590 cm −1 in the Raman spectra (Figure S16).…”

“…Meanwhile, considering the much lower competitiveness of Pt‐N 4 to snatch O 2 than Fe‐N 4 active centers, [3e] O 2 molecules bonded with Pt‐N 4 center was not considered in the calculated reaction pathways. Based on these reasons, Fe‐N 4 is demonstrated as the only active center, while Pt‐N 4 is considered as the modulator (not active center) to tune the electronic state of Fe‐N 4 for the reaction pathway, which is completely different from the previously reported “synergetic effect” on the binary metal active centers, for example, Co‐Pt‐NC, [18] Fe‐Pt‐NC, [19] Fe‐Mn‐NC, [20] Fe‐Ni‐NC [21] and Cu‐N 4 /Zn‐N 4 , [22] Fe‐N 4 /Mn‐N 4 , [10b] Fe‐N 4 /Co‐N 4 [23] and Fe‐N 4 /Ni‐N 4 [2a, 11] et al. The theoretical η ORR of each catalyst can be determined by examining the reaction Gibbs free energies of the different mechanistic steps for Fe‐N 4 and Fe‐N 4 /Pt‐N 4 .…”