Rationally Designed Mn₂O₃–ZnMn₂O₄ Hollow Heterostructures from Metal–Organic Frameworks for Stable Zn‐Ion Storage

Abstract

Mn-based oxides have sparked extensive scientific interest for aqueous Zn-ion batteries due to the rich abundance, plentiful oxidation states,a nd high output voltage.H owever, the further development of Mn-based oxides is severely hindered by the rapid capacity decayd uring cycling. Herein, atwo-step metal-organic framework (MOF)-engaged templating strategy has been developed to rationally synthesize heterostructured Mn 2 O 3 -ZnMn 2 O 4 hollowo ctahedrons (MO-ZMO HOs) for stable zinc ion storage.T he distinctive composition and hollowh eterostructure endowM O-ZMO HOs with abundant active sites,enhanced electric conductivity, and superior structural stability.Byvirtue of these advantages, the MO-ZMO HOs electrode shows high reversible capacity, impressive rate performance,and outstanding electrochemical stability.Furthermore,exsitu characterizations reveal that the charge storage of MO-ZMO HOs mainly originates from the highly reversible Zn 2+ insertion/extraction reactions.

Hierarchical Pores‐Confined Ultrasmall Cu Nanoparticles for Efficient Oxidation of 5‐Hydroxymethylfurfural

“…Initially, the HMF oxidation was carried out under 130 °C, 0.1 MPa O 2 in N,N-dimethylformamide (DMF) solvent within 8 h. Only 18.0 % DFF yield was obtained in the blank run (Table 1, entry 1). To our delight, Cu@HHC showed the best catalytic performance under relative mild conditions with a nearly quantitative DFF yield (Table 1, entry 2), outperforming the Cu/C, M@HHC, and Cu@HHC-x counterparts (Table 1, entries [3][4][5][6][7][8][9][10][11]. In a typical run, Cu@HHC achieved a turnover number (TON) value of 34.9, which is over two-fold higher than that of Cu/C and among the best catalysts reported to date (Table S1).…”

“…Due to their periodical structures and adjustable components, MOFs have exhibited remarkable potentials in the preparation of metalÀ carbon derivatives via pyrolysis for various catalytic applications. [7][8][9][10][11][12][13] However, the direct pyrolysis of MOFs often leads to the collapse of their skeletons along with undesired metal sintering, thus bringing high mass diffusion resistance and lowered accessibility of metal active sites. In order to overcome these shortcomings, various synthetic strategies, including hard/soft/ self-templating, and reagent-oriented methods, have been developed to suppress the metal agglomeration and strengthen the morphology modulation of organic ligands derived carbons during the pyrolysis.…”

“…In recent years, metal‐organic frameworks (MOFs) have emerged as a classic of coordinated polymers composed of metal nodes and organic ligands. Due to their periodical structures and adjustable components, MOFs have exhibited remarkable potentials in the preparation of metal−carbon derivatives via pyrolysis for various catalytic applications [7–13] . However, the direct pyrolysis of MOFs often leads to the collapse of their skeletons along with undesired metal sintering, thus bringing high mass diffusion resistance and lowered accessibility of metal active sites.…”

Stability Optimization Strategies of Cathode Materials for Aqueous Zinc Ion Batteries: A Mini Review

“…The adjunction of materials with a high stability structure for combination is also an exploration direction to improve the stability of cathode ( Zhang et al, 2020b ; Shan et al, 2021 ). The optimization strategy of combination engineering usually includes carbon-based materials, which can improve the electron transmission efficiency and structural stability of materials ( Yang et al, 2021 ; Zeng et al, 2021 ). Hou et al synthesized a 3D reticular graphene-based hydrated vanadium dioxide composite (O d -HVO/rG) with abundant oxygen vacancies using the solvothermal method ( Huang et al, 2021 ).…”

Enhanced cathode integrity for zinc–manganese oxide fiber batteries by a durable protective layer

“…[16][17][18] In addition, MnO 2 cathode materials are commonly troubled by dissolution due to the disproportionation of Mn element upon cycling and thus the rapid capacity decay. 19 In response, electrolytes with MnSO 4 additives are widely used to suppress Mn dissolution in Zn-MnO 2 batteries. 20 This strategy is effective in decreasing the dissolution of microscopic quantities of MnO 2 while it cannot prevent the peeling off of bulky MnO 2 precipitates, which is inevitable during the deformation of exible batteries and oen results in more severe capacity loss.…”