More Like this

1. The Nature of Lithium Bonding in C ₂ H ₂ Li ₂ , C ₆ Li ₆ , and Lithium Halide Dimers

   https://doi.org/10.1021/acs.organomet.9b00683  

   Liu, Yameng; Peng, Bin; Wang, Xiao; Xie, Yaoming; Schaefer, Henry F. (November 2019, Organometallics)
2. Lithium‐Ion Mobility in Layered Oxide Li ₂ (La _0.75 Li _0.25 )(Ta _1.5 Ti _0.5 )O ₇ Containing Lithium on both Intra and Inter‐Stack Positions

   https://doi.org/10.1002/ejic.202100950  

   Fanah, Selorm_Joy; Ramezanipour, Farshid (February 2022, European Journal of Inorganic Chemistry)

   Abstract With the aid of neutron diffraction and electrochemical impedance spectroscopy, we have demonstrated the effect of the increase in lithium concentration and distribution on Li‐ion conductivity. This has been done through the synthesis of a layered oxide Li₂(La_0.75Li_0.25)(Ta_1.5Ti_0.5)O₇, with the so‐called Ruddlesden‐Popper type structure, where bilayer stacks of (Ta/Ti)O₆octahedra are separated by lithium ions, located in inter‐stack spaces. There are also intra‐stack spaces that are occupied by a mixture of La and Li, as confirmed by neutron diffraction. The distribution of lithium over both inter‐ and intra‐stack positions leads to the enhancement of Li‐ion conductivity in Li₂(La_0.75Li_0.25)(Ta_1.5Ti_0.5)O₇compared to Li₂La(TaTi)O₇, which has a lower concentration of lithium ions, located only in inter‐stack spaces. The analyses of real and imaginary components of electrochemical impedance data confirm the enhanced mobility of ions in Li₂(La_0.75Li_0.25)(Ta_1.5Ti_0.5)O₇. While the Li‐ion conductivity needs further improvement for practical applications, the success of the strategy implemented in this work offers a useful methodology for the design of layered ionic conductors. 

   more » « less
3. C ₉ N ₄ and C ₂ N ₆ S ₃ monolayers as promising anchoring materials for lithium–sulfur batteries: weakening the shuttle effect via optimizing lithium bonds

   https://doi.org/10.1039/D1CP01022K  

   Dong, Yinan; Xu, Bai; Hu, Haiyu; Yang, Jiashu; Li, Fengyu; Gong, Jian; Chen, Zhongfang (June 2021, Physical Chemistry Chemical Physics)

   The notorious polysulfide shuttle effect is a crucial factor responsible for the degradation of Li-S batteries. A good way to suppress the shuttle effect is to effectively anchor dissoluble lithium polysulfides (LPSs, Li 2 S n ) on appropriate substrates. Previous studies have revealed that Li of Li 2 S n is prone to interact with the N of N-containing materials to form Li–N bonds. In this work, by means of density functional theory (DFT) computations, we explored the possibility to form Li bonds on ten different N-containing monolayers, including BN, C 2 N, C 2 N 6 S 3 , C 9 N 4 , a covalent triazine framework (CTF), g -C 3 N 4 , p -C 3 N 4 , C 3 N 5 , S -N 2 S, and T -N 2 S, by examining the adsorption behavior of Li 2 S n ( n = 1, 2, 3, 4, 6, 8) on these two-dimensional (2D) anchoring materials (AMs), and investigated the performance of the formed Li bonds (if any) in inhibiting the shuttle effect. By comparing and analyzing the nitrogen content, the N-containing pore size, charge transfer, and Li bonds, we found that the N content and N-containing pore size correlate with the number of Li bonds, and the formed Li–N bonds between LPSs and AMs correspond well with the adsorption energies of the LPSs. The C 9 N 4 and C 2 N 6 S 3 monolayers were identified as promising AMs in Li-S batteries. From the view of Li bonds, this work provides guidelines for designing 2D N-containing materials as anchoring materials to reduce the shuttle effect in Li-S batteries, and thus improving the performance of Li-S batteries. 

   more » « less
4. Lithium Dependent Electrochemistry of p‐Type Nanocrystalline CuCrO ₂ Films

   https://doi.org/10.1002/celc.202200825  

   Chown, Amanda L.; Yeasmin, Humaira; Paudel, Rajendra; Comes, Ryan B.; Farnum, Byron H. (December 2022, ChemElectroChem)
5. Thickness-dependent phase transition kinetics in lithium-intercalated MoS ₂

   https://doi.org/10.1088/2053-1583/ac4e9b  

   Pondick, Joshua V; Yazdani, Sajad; Kumar, Aakash; Hynek, David J; Hart, James L; Wang, Mengjing; Qiu, Diana Y; Cha, Judy J (February 2022, 2D Materials)

   Abstract The phase transitions of two-dimensional (2D) materials are key to the operation of many devices with applications including energy storage and low power electronics. Nanoscale confinement in the form of reduced thickness can modulate the phase transitions of 2D materials both in their thermodynamics and kinetics. Here, using in situ Raman spectroscopy we demonstrate that reducing the thickness of MoS 2 below five layers slows the kinetics of the phase transition from 2H- to 1T′-MoS 2 induced by the electrochemical intercalation of lithium. We observe that the growth rate of 1T′ domains is suppressed in thin MoS 2 supported by SiO 2 , and attribute this growth suppression to increased interfacial effects as the thickness is reduced below 5 nm. The suppressed kinetics can be reversed by placing MoS 2 on a 2D hexagonal boron nitride ( h BN) support, which readily facilitates the release of strain induced by the phase transition. Additionally, we show that the irreversible conversion of intercalated 1T′-MoS 2 into Li 2 S and Mo is also thickness-dependent and the stability of 1T′-MoS 2 is significantly increased below five layers, requiring a much higher applied electrochemical potential to break down 1T′-MoS 2 into Li 2 S and Mo nanoclusters. 

   more » « less