Ultrathin α-MnO2 Nanosheets Wrapped on Acanthosphere-like Microspheres with Highly Reversible Performance for Energy Storage

In Situ Growth of Zeolitic Imidazolate Framework‐67‐derived Nanoporous Carbon@K0.5Mn2O4 for High‐Performance 2.4 V Aqueous Asymmetric Supercapacitors

“…As shown in Figure 3a and Figure S5, au niform layer of K 0.5 Mn 2 O 4 nanosheets were wrapped on each NC particle,d emonstrating the great potentialo fo ur synthesis methodf or large-scale preparation.T EM and highresolution TEM (HRTEM)w ere employed to furthere xplore the morphology and structure of NCMO. [44,45] Twop eaks in the K2ps pectruma t2 92.8 and 295.6 e, with a splitting of 2.8 eV,d emonstrated the existence of K + · [46] The O1sp eak can be deconvoluted into three types of contributions for oxygen species, corresponding to MnÀO( 529.96 eV), CÀO( 531.8 eV) and HÀOÀH( 534.1 eV) bonds, [44] as shown in Figure 4c.Aprominent peak appeared at 284.7 eV in the C1s spectrum,w hich suggested the presence of sp 2 -hybridized carbon (C=C), and another peak appeared at 285.8 eV,w hich was attributed to the CÀOb onds, [47] as shown in Figure 4d. An enlarged TEM image taken The X-ray photoelectron spectroscopy (XPS) measurements were used to confirm the surface structureo ft he NCMO.F igure 4a and bs how the high-resolution XPS spectra of Mn 2p and K2p, respectively.T wo major peaks were observed at 642.5 and 653.7 eV,w hich were assigned to Mn 2p 3/2 and Mn 2p 1/2 ,r espectively,c onfirming the presence of Mn 4 + .…”

“…The X-ray photoelectron spectroscopy (XPS) measurements were used to confirm the surface structureo ft he NCMO.F igure 4a and bs how the high-resolution XPS spectra of Mn 2p and K2p, respectively.T wo major peaks were observed at 642.5 and 653.7 eV,w hich were assigned to Mn 2p 3/2 and Mn 2p 1/2 ,r espectively,c onfirming the presence of Mn 4 + . [44,45] Twop eaks in the K2ps pectruma t2 92.8 and 295.6 e, with a splitting of 2.8 eV,d emonstrated the existence of K + · [46] The O1sp eak can be deconvoluted into three types of contributions for oxygen species, corresponding to MnÀO( 529.96 eV), CÀO( 531.8 eV) and HÀOÀH( 534.1 eV) bonds, [44] as shown in Figure 4c.Aprominent peak appeared at 284.7 eV in the C1s spectrum,w hich suggested the presence of sp 2 -hybridized carbon (C=C), and another peak appeared at 285.8 eV,w hich was attributed to the CÀOb onds, [47] as shown in Figure 4d.…”

Surface‐Modification‐Assisted Construction of Hierarchical Double‐Walled MnO2 Hollow Nanofibers for High‐Performance Supercapacitor Electrode

“…Particularly, TMOs are generally employed as PCs owing to the multiple oxidation states for rich faradaic reactions, which could meet the demands of high‐energy SCs . Among the diverse TMOs, MnO 2 , with a lower cost and toxicity than RuO 2 , a wider electrochemical potential window than both of Co 3 O 4 and NiO in aqueous electrolytes, a high theoretical capacity (1370 F g −1 ), as well as abundant storage in earth, has been intensively investigated . It is known that the electrochemical property of MnO 2 is strongly influenced by its crystal structure, crystallinity and morphology ,.…”