Conclusions
In summary, we have demonstrated surface microenvironment optimization
as an effective way to design highly active ORR catalyst, serving as air
electrode for neutral ZABs. Benefiting from the optimal surface
microenvironment induced synergistic effects between different active
sites, the achieved Pt-SMO-Co2N NWs presented
extraordinary ORR activity. In 2.0 M PBS (pH=7.0),
Pt-SMO-Co2N NWs showed a positive onset potential of
0.960V and a half-wave potential of 0.812 V, which is 92mV higher than
that of commercial Pt/C. The power density of neutral ZABs taking
Pt-SMO-Co2N NWs as cathode catalyst could reach 67.9
mW*cm−2, outperforming commercial Pt/C under the same
circumstance and displayed barely decay after 80 hours’ discharge-charge
test. Moreover, based on the ideal material platform built on
Pt-SMO-Co2N NWs, in-depth characterization and
mechanistic understanding of ORR was disclosed. Our work reveals a new
strategy for the ORR catalyst design through the construction of optimal
surface microenvironment and offers new insights toward the key role of
activating H2O and facilitating proton transfer process
in ORR catalysis.
ASSOCIATED CONTENT
XRD patterns, TEM images and additional electrochemical date are
included in the supporting information. This material is available free
of charge via the Internet at http://pubs.acs.org.
AUTHOR INFORMATION
Corresponding Author
czwu@ustc.edu.cn;
yxie@ustxc.edu.cn
Author Contributions
§These authors contributed equally.
Notes The authors declare no competing financial interests.
ACKNOWLEDGMENT
This work was financially supported by the National Basic Research
Program of China (2017YFA0206702),
Natural Science Foundation of China
(No. 21925110, 21890751), China Postdoctoral Science Foundation
(2019TQ0299) and Fundamental Research Funds for the Central Universities
(No. WK 2060190084, No. WK 5290000001). The authors thank Dr Jie Tian
and Dr Huijuan Wang at Engineering and Materials Science Experiment
Centre for the help of HRTEM experiments. The authors also appreciate
the support from the Major/Innovative Program of Development Foundation
of Hefei Center for Physical Science and Technology. This work was
partially carried out at the USTC Center for Micro and Nanoscale
Research and Fabrication.
REFERENCES
1. Larcher, D. & Tarascon, J. M. Towards greener and more sustainable
batteries for electrical energy storage. Nat. Chem. 7 ,
19-29, doi:10.1038/nchem.2085 (2015).
2. Aricò, A. S., Bruce, P., Scrosati, B., Tarascon, J.-M. & van
Schalkwijk, W. Nanostructured materials for advanced energy conversion
and storage devices. Nat. Mater. 4 , 366-377,
doi:10.1038/nmat1368 (2005).
3. Dresselhaus, M. S. & Thomas, I. L. Alternative energy technologies.Nature 414 , 332-337, doi:10.1038/35104599 (2001).
4. Suntivich, J. et al. Design principles for oxygen-reduction activity
on perovskite oxide catalysts for fuel cells and metal–air batteries.Nat. Chem. 3 , 546-550, doi:10.1038/nchem.1069 (2011).
5. Debe, M. K. Electrocatalyst approaches and challenges for automotive
fuel cells. Nature 486 , 43-51, doi:10.1038/nature11115
(2012).
6. Tang, C., Wang, B., Wang, H.-F. & Zhang, Q. Defect engineering
toward atomic Co–Nx–C in hierarchical graphene for rechargeable
flexible solid Zn-air batteries. Adv. Mater. 29 ,
1703185, doi:10.1002/adma.201703185 (2017).
7. Yu, P. et al. Co Nanoislands rooted on Co–N–C nanosheets as
efficient oxygen electrocatalyst for Zn–air batteries. Adv.
Mater. 31 , 1901666, doi:10.1002/adma.201901666 (2019).
8. Meng, F., Zhong, H., Bao, D., Yan, J. & Zhang, X. In situ coupling
of strung Co4N and intertwined N–C fibers toward
free-standing bifunctional cathode for robust, efficient, and flexible
Zn–air batteries. J. Am. Chem. Soc. 138 , 10226-10231,
doi:10.1021/jacs.6b05046 (2016).
9. Jiang, Y. et al. Interpenetrating triphase cobalt-based
nanocomposites as efficient bifunctional oxygen electrocatalysts for
long-lasting rechargeable Zn–air batteries. Adv. Energy. Mater.8 , 1702900, doi:10.1002/aenm.201702900 (2018).
10. Tong, Y. et al. A bifunctional hybrid electrocatalyst for
oxygen reduction and evolution: cobalt oxide nanoparticles strongly
coupled to B, N-decorated graphene. Angew. Chem. Int. Ed.56 , 7121-7125, doi:10.1002/anie.201702430 (2017).
11. Li, Y. & Dai, H. Recent advances in zinc–air batteries.Chem. Soc. Rev. 43 , 5257-5275, doi:10.1039/C4CS00015C
(2014).
12. Xia, B. Y. et al. A metal–organic framework-derived
bifunctional oxygen electrocatalyst. Nat. Energy. 1 ,
15006, doi:10.1038/nenergy.2015.6 (2016).
13. Sumboja, A. et al. Durable rechargeable zinc-air batteries
with neutral electrolyte and manganese oxide catalyst. J. Power
Sources. 332 , 330-336, doi:10.1016/j.jpowsour.2016.09.142
(2016).
14. Su, Y. et al. A highly efficient catalyst toward oxygen
reduction reaction in neutral media for microbial fuel cells. Ind.
Eng. Chem. Res. 52 , 6076-6082, doi:10.1021/ie4003766 (2013).
15. Clark, S., Latz, A. & Horstmann, B. Rational development of neutral
aqueous electrolytes for zinc-air batteries. ChemSusChem.10 , 4735-4747, doi:10.1002/cssc.201701468 (2017).
16. Xie, L. et al. Molecular engineering of a 3D self-supported
electrode for oxygen electrocatalysis in neutral media. Angew.
Chem. Int. Ed. 58 , 18883-18887, doi:10.1002/anie.201911441
(2019).
17. Jung, J.-I., Jeong, H. Y., Lee, J.-S., Kim, M. G. & Cho, J. A
bifunctional perovskite catalyst for oxygen reduction and evolution.Angew. Chem. Int. Ed. 53 , 4582-4586,
doi:10.1002/anie.201311223 (2014).
18. Ma, T. Y., Ran, J., Dai, S., Jaroniec, M. & Qiao, S. Z.
Phosphorus-Doped Graphitic Carbon Nitrides Grown In Situ on Carbon-Fiber
Paper: Flexible and Reversible Oxygen Electrodes. Angew. Chem.
Int. Ed. 54 , 4646-4650, doi:10.1002/anie.201411125 (2015).
19. Gong, M. et al. Nanoscale nickel oxide/nickel
heterostructures for active hydrogen evolution electrocatalysis.Nat. Commun. 5 , 4695, doi:10.1038/ncomms5695 (2014).
20. Lu, X. F., Chen, Y., Wang, S., Gao, S. & Lou, X. W. Interfacing
manganese oxide and cobalt in porous graphitic carbon polyhedrons boosts
oxygen electrocatalysis for Zn–air batteries. Adv. Mater.31 , 1902339, doi:10.1002/adma.201902339 (2019).
21.Xing, Z., Hu, L., Ripatti, D. S., Hu, X. & Feng, X. Enhancing carbon
dioxide gas-diffusion electrolysis by creating a hydrophobic catalyst
microenvironment. Nat. Commun. 12 , 136,
doi:10.1038/s41467-020-20397-5 (2021).
22. Guo, C. et al. Engineering High-Energy Interfacial Structures
for High-Performance Oxygen-Involving Electrocatalysis. Angew.
Chem. Int. Ed. 56 , 8539-8543, doi:10.1002/anie.201701531
(2017).
23. Yu, L., Yi, Q., Li, G., Chen, Y. & Yang, X. FeCo-Doped Hollow
Bamboo-Like C-N Composites as Cathodic Catalysts for Zinc-Air Battery in
Neutral Media. J. Electrochem. Soc 165 , A2502-A2509,
doi:10.1149/2.0481811jes (2018).
24. Shao, M., Chang, Q., Dodelet, J.-P. & Chenitz, R. Recent Advances
in Electrocatalysts for Oxygen Reduction Reaction. Chem. Rev.116 , 3594-3657, doi:10.1021/acs.chemrev.5b00462 (2016).
25. Jin, H. et al. In situ Cobalt–Cobalt Oxide/N-Doped Carbon
Hybrids As Superior Bifunctional Electrocatalysts for Hydrogen and
Oxygen Evolution. J. Am. Chem. Soc. 137 , 2688-2694,
doi:10.1021/ja5127165 (2015).
26. Liu, S. et al. Dual Modulation via Electrochemical Reduction
Activiation on Electrocatalysts for Enhanced Oxygen Evolution Reaction.ACS Energy Lett. 4 , 423-429,
doi:10.1021/acsenergylett.8b01974 (2019).
27. Kerrec, O., Devilliers, D., Groult, H. & Marcus, P. Study of dry
and electrogenerated Ta2O5 and Ta/Ta2O5/Pt structures by XPS.Mater. Sci. Eng. B. 55 , 134-142,
doi:https://doi.org/10.1016/S0921-5107(98)00177-9 (1998).
28. Chen, Y. et al. Atomic-Level Modulation of Electronic Density
at Cobalt Single-Atom Sites Derived from Metal–Organic Frameworks:
Enhanced Oxygen Reduction Performance. Angew. Chem. Int. Ed. doi:
10.1002/anie.202012798.
29. Zhou, T. et al. Ultrathin Cobalt Oxide Layers as
Electrocatalysts for High-Performance Flexible Zn–Air Batteries.Adv. Mater. 31 , 1807468, doi:10.1002/adma.201807468
(2019).
30. Wang, Y. et al. Synergistic Mn-Co catalyst outperforms Pt on
high-rate oxygen reduction for alkaline polymer electrolyte fuel cells.Nat. Commun. 10 , 1506, doi:10.1038/s41467-019-09503-4
(2019).
31. Subbaraman, R. et al. Trends in activity for the water
electrolyser reactions on 3d M(Ni,Co,Fe,Mn) hydr(oxy)oxide catalysts.Nat. Mater. 11 , 550-557, doi:10.1038/nmat3313 (2012).
32. Xu, K. et al. Controllable Surface Reorganization Engineering
on Cobalt Phosphide Nanowire Arrays for Efficient Alkaline Hydrogen
Evolution Reaction. Adv. Mater. 30 , 1703322,
doi:10.1002/adma.201703322 (2018).