Mn3O4 nanocrystalline@carbon nanotube-carbon nanotube for long-lifetime and excellent rate-capability zinc-ion storage

Metal–organic framework derived tunnel structured MnO as the cathode material for high performance aqueous zinc-ion batteries

“…2,34,36,38,[40][41][42][43] Considering the faster migration and smaller radius of H + than Zn 2+ , H + ions are easier to insert into Mn-based cathode materials than Zn 2+ ions. 2,36,42,44 Therefore, H + can participate in both reactions of Mn 4+ 4 Mn 3+ and Mn 3+ 4 Mn 2+ , resulting in the conversion of MnOOH and MnO. 2,37,38,40,[43][44][45] At the same time, the participation of H + in the reaction would lead to the formation of OH − , which would then react with ZnSO 4 $7H 2 O to form ZnSO 4 $3Zn(OH) 2 $5H 2 O (JCPDS No.…”

“…2,36,42,44 Therefore, H + can participate in both reactions of Mn 4+ 4 Mn 3+ and Mn 3+ 4 Mn 2+ , resulting in the conversion of MnOOH and MnO. 2,37,38,40,[43][44][45] At the same time, the participation of H + in the reaction would lead to the formation of OH − , which would then react with ZnSO 4 $7H 2 O to form ZnSO 4 $3Zn(OH) 2 $5H 2 O (JCPDS No. 78-0246).…”

“…A similar phenomenon has also been observed in the Mn-based composite cathode, especially with high surface area carbon additives at low current densities. [29][30][31]42,44 For example, Kim et al investigated different types of carbon additives and showed that the surface of the carbon additives can provide a greater number of deposition sites for Mn 2+ ions in the early stages of nucleation and growth. 29 Fig.…”

MOF-Derived Mn3O4@C Hierarchical Nanospheres as Cathodes for Aqueous Zinc-Ion Batteries

“…30,31 For instance, Tong and co-workers demonstrated that nanocrystalline Mn 3 O 4 on mesoporous carbon materials has a high capacity of 234 mAh g −1 at 1 A g −1 and a rate performance of 49 mAh g −1 at 5 A g −1 . 32 Ren et al synthesized Mn 3 O 4 @ carbon nanotubes based on the synergistic effect of the nanoscale. CNTs@Mn 3 O 4 exhibits a specific capacity of 310 mAh g −1 at 0.1 A g −1 and a long cycle life (123 mAh g −1 after 500 cycles).…”

“…The high conductivity, enhanced specific surface area, more electroactive sites, accommodation of volume expansion, and protective layers of carbon materials are used to improve the zinc storage capacity of the materials. , The commonly used carbon materials mainly include carbon fiber, graphene, and porous carbon. In general, there are two aspects to the research: (1) compounds or coatings of Mn 3 O 4 are made from porous carbon, graphene, or carbon nanotubes, and their high conductivity and electrochemical activity are used to improve the capacity and rate property of the material. , For instance, Tong and co-workers demonstrated that nanocrystalline Mn 3 O 4 on mesoporous carbon materials has a high capacity of 234 mAh g –1 at 1 A g –1 and a rate performance of 49 mAh g –1 at 5 A g –1 . Ren et al.…”