In Situ Subangstrom‐Thick Organic Engineering Enables Mono‐scale, Ultrasmall ZnO Nanocrystals for a High Initial Coulombic Efficiency, Fully Reversible Conversion, and Cycle‐Stable Li‐Ion Storage

Abstract

A solid electrolyte interphase (SEI)‐free surface and fully reversible conversion are simultaneously realized in the Li‐ion storage of a specially designed ZnO porous nanocomposite with in situ surfaces/interfaces organic encapsulation for the first time. The built‐in oxygen‐ and/or moisture‐isolating organic layer of subangstrom thickness not only avoids the SEI formation, but also guarantees monodisperse and ultrasmall dimensions of ZnO nanocrystals, which are crucial for the high initial Coulombic efficiency (ICE) and fully reversible conversion. Benefiting from the high ICE up to 91.4%, stable long‐term cyclibility (95% capacity retention at 1 A g−1 after 1400 cycles), and no sacrificing Li‐ion storage capability (868 mAh g−1 at 0.1 A g−1), the ZnO nanocomposite demonstrates the highest initial Li‐ion utilization efficiency (ILUE, ≈85.4%) among previous transition metal oxide–based full cells.

Multiple Active Sites: Lithium Storage Mechanism of Cu‐TCNQ as an Anode Material for Lithium‐Ion Batteries

“…[35,36] In the discharge/charge cycle test, Cu-TCNQm ight evolvei nto ultra-small nanocrystals, and the enhanced organic surfaces/interfaces along with pseudocapacitancem ight cause the rising tendency of cycling. [34,37] As ac ontrast, the specific capacityo fC u-TCNQ between 0.2-3.0 Vd ecreased to almost zero in the first 7s cans ( Figure S1). The relatedr esearch work is still in progress.…”

Coherent Solution‐phase Synthesis of a Germanium‐Graphitic Nanocomposite and Its Evaluation for Lithium‐Ion Battery Anodes: Non‐innocent Role of the Mashima Reagent

“…In addition, the SEI layer formed in this case continuously ruptures and reforms thereby consuming Li + during the first 100 cycles. Worth mentioning, a SEI‐free surface is advantageous in terms of obtaining high initial Coulombic efficiency and stable long‐term cycling as has been reported in the case of ZnO porous nanocomposite with surface/interface organic encapsulation . After 250 cycles, 88% of the discharge capacity at 100 th cycle=456 mAh g −1 is retained (Figure S12, see SI).…”

“…Worth mentioning, a SEI-free surface is advantageous in terms of obtaining high initial Coulombic efficiency and stable long-term cycling as has been reported in the case of ZnO porous nanocomposite with surface/interface organic encapsulation. [36] After 250 cycles, 88% of the discharge capacity at 100 th cycle = 456 mAh g À 1 is retained ( Figure S12, see SI). On the basis of 57 wt.% of Ge NCs in the nano-composite, the calculated reversible capacity of Ge NCs was 705 mAh g À 1 at the 250 th cycle.…”

Scalable Synthesis of One‐Dimensional Mesoporous ZnMnO3 Nanorods with Ultra‐Stable and High Rate Capability for Efficient Lithium Storage

“…Such novel porousf eatures and nanoscale active particles would effectively generate extra active sites for efficient lithium storage,p romote the transport of ions/electrons, and offer the requisite buffer space to accommodate the volumev ariation of the ZMO-NRs electrode during repeated cycling, thereby enhancing its electrochemical behaviors. [21,22] In addition, the high-resolution TEM (HRTEM) image (Figure 4g)c learlye vidences lattice fringesw ith inter-planar spacings of 0.30 and 0.48 nm, corresponding to the (2 20)a nd (111)c rystal planes of ZnMnO 3 ,r espectively. [8,9] The selectivea rea electron diffraction (SAED) pattern (inset in Figure 4g)a lso presents as et of diffraction rings with the indexed (4 00), (2 22), and (2 20) planes, indicating the polycrystalline nature of the ZMO-NRs.…”