Y.J. Li, J.Q. Qin, Y.J. Ding, J.X. Ma, P. Das, H.Q. Liu, Z.-S. Wu* and X.H. Bao
ACS Catalysis, 2022, 12, 12765-12773.
DOI: 10.1021/acscatal.2c02544 [PDF]
Designing oxygen catalysts with well-defined shapes and high-activity crystal facets is of great importance to boost catalytic performance of Li-O2 batteries, but challenging. Herein, we report the facetengineering of ultra thin Mn3O4 nanosheet (NS) with dominant (101) crystal planes on graphene (Mn3O4NS/G) as efficient and durable oxygen catalystsfor high-performance Li-O2batteries with ultrahigh capacity and long-term stability.Notably, the Mn3O4NS/G with the (101) facets and enriched oxygen vacancies offer a lower charge overpotential of 0.86 V than that of Mn3O4 nanoparticleson graphene (1.15 V). Further, Mn3O4NS/Gcathode exhibits long-term stability over 1300 h and ultrahigh specific capacity up to 35583mAh g-1at 200 mA g-1, outperforming most Mn-based oxides for Li-O2 batteries reported.Both the experimental and theoretical results prove the lower adsorption energy of Mn3O4 (101) for Li2O2 in comparison with Mn3O4(211), manifesting the easier decomposition of Li2O2during the charging process.This work will open many opportunities to engineer Mn-based materials with defined crystal facet for high-performance Li-O2 batteries.
