possess lower hardness, higher strength, higher elasticity, higher tensile strength, lower internal energy, higher interatomic forces, lower viscosity coefficient, larger surface area, higher chemical stability, and strong corrosion resistance compared with their crystalline counterparts. [1][2][3] Based on the anionic constituents, amorphous materials could be categorized as oxides, sulfides, phosphates, etc. Among them, amorphous metal oxide family is of great importance owing to its widespread applications in a variety of areas such as batteries, supercapacitors, electronics, conducting films, multilayered transistors, electrochromic displays, nonvolatile memories, and the like. [4][5][6] As the basic building blocks, metaloxide (M-O) polyhedra are responsible for the essential features of the electronic band structure in amorphous metal oxides (AMOs). [3] AMO materials differ from their crystalline counterparts in the arrangement of M-O polyhedra, in which a random network arrangement of distorted polyhedra with short-range ordering is presented rather than maintaining perfect periodicity. [7,8] The coordination number of the M-O polyhedra, namely, the number of anions bonded to the metal cation, constitutes a crucially decisive factor for the unique properties of AMOs. Multiple polyhedra are interconnected through different types of sharing configurations known as edge sharing, corner sharing, and face sharing of the oxygen atoms. The combination of different sharing geometries also affects the properties of AMOs. [9] In other words, AMOs are formed by the superposition of the distorted M-O polyhedra to form network arrays through a random package. Long-range structural disorder in the AMO reduces scattering mean free path, and the lack of grain boundaries makes the electronic properties identical within large areas. These unique characteristics make them suitable for flexible electronics such as flexible films, intervening layers, thin film transistors, etc. [10][11][12] In recent years, there are numerous reports pointing out the advantages of AMOs over the crystalline counterparts in many electrochemical applications. [13][14][15][16][17] For example, the inherent disorderliness in the structural arrangement and rich defects are evidenced to be highly constructive to improve the alkali ion diffusion through the lattice. [18,19] As for intercalation-type electrodes in lithium-ion batteries (LIBs), amorphous materials Amorphous metal oxides (AMOs) have aroused great enthusiasm across multiple energy areas over recent years due to their unique properties, such as the intrinsic isotropy, versatility in compositions, absence of grain boundaries, defect distribution, flexible nature, etc. Here, the materials engineering of AMOs is systematically reviewed in different electrochemical applications and recent advances in understanding and developing AMO-based high-performance electrodes are highlighted. Attention is focused on the important roles that AMOs play in various energy storage and conversion technologies...

Additive manufacturing industries have been focusing on the development of novel ink formulation strategies, that can incorporate functional materials for printing high-efficient electronic patterns for flexible devices. As such printed...

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Structural instability is the major obstacle in the Li2FeSiO4/C cathode during charge and discharge process, which can be improved by the substitution of cations in the host cage. In this study, the transition metal ions with different valence (Ag1+, Zn2+, Cr3+, and Ti4+) have been substituted in Li2FeSiO4/C via modified sol‐gel method and the impact on the structural, electrical, and electrochemical performances has been systematically explored. The Rietveld‐refined XRD pattern and HR‐TEM (SAED) result reveal that all the prepared samples maintain orthorhombic structure (S.G‐ Pmn21). The FE‐SEM and TEM micrographs of bare and doped Li2FeSiO4/C display nanoparticle formation with 20‐40 nm size. Among different cation‐substituted silicates, Li2Fe0.9Ti0.1SiO4/C sample exhibits an excellent total conductivity of 1.20 × 10−4 S cm−1 which is one order of magnitude higher than the bare Li2FeSiO4/C sample. The galvanostatic charge‐discharge curves and cyclic voltammetric analysis reveal that the Li2Fe0.9Ti0.1SiO4/C material provides an excellent initial specific capacity of 242 mAh g−1 and maintains a capacity of 226 mAh g−1 after 50 cycles with capacity retention of 93.38%. The Ti doping is a promising strategy to overcome the capacity fading issues, by preventing the structural collapse during Li‐ion intercalation/de‐intercalation processes in the Li2FeSiO4/C electrode through the strong hybridization between the 3d and 4s orbitals in titanium and 2p orbital in oxygen.

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