Facile one-pot synthesis of Ge/TiO₂ nanocomposite structures with improved electrochemical performance

Abstract

Ge/TiO2 nanocomposite structures as anodes for LIBs with improved electrochemical performance were synthesized using a facile one-pot method.

A Synergistic Effect of Na+ and Al3+ Dual Doping on Electrochemical Performance and Structural Stability of LiNi0.88Co0.08Mn0.04O2 Cathodes for Li-Ion Batteries

“…To investigate the reaction kinetics of bare NCM, NNCM, NCMA, and NNCMA, GITT experiments were conducted; the results are presented in Figure d. GITT analysis was conducted in the voltage range of 2.8–4.35 V vs Li/Li + at an applied current of 0.1 C at room temperature alternating between charging for 2000 s and rest for 2000 s. The Li-ion diffusion coefficient can be calculated as follows: − where m , V , and M are the mass, molar volume, and molecular weight of the cathode active material, respectively; S is the electrode area; τ is the duration of the current pulse; Δ E s and Δ E t are the steady-state voltage changes because of the current pulse and steady-state voltage change during the constant current pulse, respectively, which prevent the decrease in iR ; and L is the length of the Li-ion diffusion pathway.…”

Germanium Nanowires via Molten-Salt Electrolysis for Lithium Battery Anode

“…During the anodic process, the peak at 0.59 V represents the dealloying of Li x Ge into Ge. 44,45 Upon subsequent cycles, the alloying/dealloying processes of the Ge nanowires reversibly take place. The cationic peaks located at 0.52, 0.35, and 0.09 V could be ascribed to the formation of Li 9 Ge 4 , Li 7 Ge 2 , and Li 15 Ge 4 (Li 22 Ge 5 ).…”

“…In the first cathodic scan, there is a peak between 0.25 and 0.12 V, indicating the alloying reaction of Ge into Li x Ge and the formation of a stable SEI. During the anodic process, the peak at 0.59 V represents the dealloying of Li x Ge into Ge. , Upon subsequent cycles, the alloying/dealloying processes of the Ge nanowires reversibly take place. The cationic peaks located at 0.52, 0.35, and 0.09 V could be ascribed to the formation of Li 9 Ge 4 , Li 7 Ge 2 , and Li 15 Ge 4 (Li 22 Ge 5 ). , During the anionic process, a strong peak at 0.59 V and an inconspicuous peak at 0.42 V are detected, indicating that Li 15 Ge 4 converts into heterogeneous Li x Ge and eventually Ge (see below) …”

In-situ construction of conducting alloy interphase towards modulating Li-ion storage kinetics

“…These electrochemical performance results indicate that the Ge@MoGe 2 @MoS 2 electrode exhibits excellent specific capacity and preeminent cycling performance compared to the pure MoS 2 electrode. This high capacity and long cycling performance of the Ge@MoGe 2 @MoS 2 anodes are superior to most other previously reported Ge-based anode materials, as listed in Table S3 [ 37,41,[45][46][47]50,[52][53][54]56,57]. The excellent cycling performance of Ge@MoGe 2 @MoS 2 in LIBs is owing to: (i) The ternary composite material composed of Ge nanoparticle with high specific capacity is beneficial to produce high battery capacity; (ii) the as-generated MoGe 2 interface, chemically bonding with both Ge and MoS 2 , possesses multi-fold merits, including the maintaining stable framework of electrochemically inactive Mo matrix to buffer the strain-stress effect and the ''welding spot" effects to facilitate the efficient Li + /e À conduction.…”