Zn Single Atom Catalyst for Highly Efficient Oxygen Reduction Reaction

Abstract

The authors report first a new type of nitrogen-triggered Zn single atom catalyst, demonstrating high catalytic activity and remarkable durability for the oxygen reduction reaction process. Both X-ray absorption fine structure spectra and theoretical calculations suggest that the atomically dispersed Zn-N 4 site is the main, as well as the most active, component with O adsorption as the rate-limiting step at a low overpotential of 1.70 V. This work opens a new field for the exploration of high-performance Pt-free electrochemical oxygen reduction catalysts for fuel cells.

Boosting oxygen reduction and Zn–air battery performance via the rational design of interlayer pyridinic nitrogen in Zn-N 4 -hierarchical porous carbon nanofibers

“…2b) revealed ve distinct chemical states: pyridinic-N (398.4 eV, 27.06%), pyrrolic-N (400.2 eV, 15.12%), graphitic-N (401.2 eV, 28.36%), Zn-N (399.4 eV, 23.31%), and oxidized-N species (403.0 eV, 6.14%) (Table S2 †), 38,39 indicating that the Zn-N bonds of ZIF-8 were retained during pyrolysis to generate Zn-N 4 -HPCNFs-28. [40][41][42][43][44] This result is consistent with the TEM observations. Furthermore, the Zn 2p 3/2 peaks for Zn-N 4 were detected at 1022.0 and 1045.1 eV (Fig.…”

Regulation of the coordination number of Zn single atoms to boost electrochemical sensing of H 2 O 2

“…4(C), the high-resolution XPS spectrum of Zn shows that the valence state of Zn single atoms is significantly higher than zero, which may be related to the coordination structure of metal single atoms. 26 This is consistent with the characterization results of synchrotron X-ray adsorption spectroscopy shown in Fig. 3(D).…”

Turning the Inert Element Zinc into an Active Single‐Atom Catalyst for Efficient Fenton‐Like Chemistry

“…The first‐shell EXAFS fitting results (Figure 1f and Table S2) show the average coordination number for Zn around N is 3.8, indicating that each Zn atom is coordinated with four N atoms in SA−Zn−NC. In the Zn 2p XPS spectrum of SA−Zn−NC (Figure S5), two peaks appear at approximately 1022 and 1045 eV corresponding to the +2 state of Zn, [24] consistent with the above XANES analysis. As compared with the Zn‐free NC sample, a new peak emerges at 399.1 eV in the XPS spectrum of N 1s for SA−Zn−NC (Figure 1g), which refers to the Zn−N species and thus substantiates the formation of Zn−N bonds in SA−Zn−NC [25] .…”