Interfacial Designing of MnO₂ Half‐Wrapped by Aromatic Polymers for High‐Performance Aqueous Zinc‐Ion Batteries

Abstract

Due to the excellent specific capacity and high working voltage, manganese oxide (MnO 2 ) has attracted considerable attention for aqueous zinc-ion batteries (AZIBs). However, the irreversible structural collapse and sluggish ionic diffusion lead to poor rate capability and inferior lifespan. Herein, we proposed a novel organic/inorganic hybrid cathode of carbon-based poly(4,4'-oxybisbenzenamine)/MnO 2 (denoted as C@PODA/MnO 2 ) for AZIBs. Various in/ex situ analyses and theoretical calculations prove that PODA chains with C=N groups can provide a more active surface/ interface for ion/electron mobility and zinc ion storage in the hybrid cathode. More importantly, newly formed MnÀ N interfacial bonds can effectively promote ion diffusion and prevent Mn atoms dissolution, enhancing redox kinetics and structural integrity of MnO 2 . Accordingly, C@PODA/MnO 2 cathode exhibits high capacity (321 mAh g À 1 or 1.7 mAh cm À 2 at 0.1 A g À 1 ), superior rate performance (88 mAh g À 1 at 10 A g À 1 ) and excellent cycling stability over 2000 cycles. Hence, rational interfacial designs shed light on the development of organic/ inorganic cathodes for advanced AZIBs.

Trace Amounts of Triple-Functional Additives Enable Reversible Aqueous Zinc-Ion Batteries from a Comprehensive Perspective

“…Impressively, a better redox reaction kinetic behaviors were gained in DE electrolyte due to less polarization reflecting as relatively small potential differences between two pairs of redox peaks (Fig. 5 a) [ 53 , 54 ]. The rate performance of full cells using different electrolytes were illustrated in Fig.…”

Hybrid Superlattice‐Triggered Selective Proton Grotthuss Intercalation in δ‐MnO2 for High‐Performance Zinc‐Ion Battery

“…On the contrary, the specific capacity of elemental MnO 2 rapidly decays to 58.5 mAh g −1 at 12.5 A g −1 . According to the literature, PVP−MnO 2 hybrid superlattice provides improved rate capability among recently reported Mn‐based ZIBs, such as Ti−MnO 2 , [27] K, Fe−ZMO, [28] α‐Mn 2 O 3 , [29] m‐MO, [30] MnO 2 @PANI, [6] ZNCMO@N‐rGO, [31] C@PODA/MnO 2 ‐6, [32] 100TiO 2 @Zn−MnO 2 , [33] Zn//OD−ZMO@PEDOT, [34] PANI‐intercalated MnO 2 [19a] (Figure 3d). Cycle stability tests of PVP−MnO 2 and MnO 2 are employed as well.…”

Local Electric Field Induced by Atomic‐Level Donor–Acceptor Couple of O Vacancies and Mn Atoms Enables Efficient Hybrid Capacitive Deionization

“…Figure a presents the Mn 2p spectra of two samples, and a slight Mn 3+ and Mn 4+ peaks shift from 653.74 and 655.30 eV to 653.25 and 654.45 eV can be observed after NaBH 4 treatment, demonstrating the increased average electron density on Mn atoms in MnO 2− x . [ 25 ] Furthermore, STEM‐EELS in Figure 2b was performed to disclose the average electron densities on Mn and O atoms, and the related results are listed in Table S2, Supporting Information. [ 18,20a ] Two peaks centered ≈ 640 eV are the characteristic “white lines” (L 2 , L 3 ) for Mn atoms, resulting from the electron excitations from the core states 2p 1/2 and 2p 3/2 to unoccupied 3d atomic orbitals.…”