Molecular Layer Deposition of Crosslinked Polymeric Lithicone for Superior Lithium Metal Anodes

Abstract

In this work, we for the first time developed a novel lithium-containing crosslinked polymeric material, a lithicone that enables excellent protection effects over lithium (Li) metal anodes. This new lithicone was synthesized via an accurately controllable molecular layer deposition (MLD) process, in which lithium tert-butoxide (LTB) and glycerol (GL) were used as precursors. The resultant LiGL lithicone was analyzed using a suite of characterizations. Furthermore, we found that the LiGL thichicone could serve as an exceptional polymeric protection film over Li metal anodes. Our experimental data revealed that the Li electrodes coated by this LiGL lithicone can achieve a superior cycling stability, accounting for an extremely long cyclability of >13,600 Li-stripping/plating cycles and having no failures so far in Li/Li symmetric cells at a current density of 5 mA/cm2 and an areal capacity of 1 mAh/cm2. We found that, with a sufficient protection by this LiGL coating, Li electrodes could realize long-term stable cyclability with little formation of Li dendrites and solid electrolyte interphase. This novel LiGL represents a facile and effective solution to the existing issues of Li anodes and potentially paves a technically feasible route for lithium metal batteries.

Hierarchically Self‐Assembled MOF Network Enables Continuous Ion Transport and High Mechanical Strength

“…In contrast, MOF powder-PVDF and pure PVDF solid electrolytes show noticeably unstable and short-circuited cyclic performance, respectively, indicating the poor ability to suppress the growth of lithium dendrites and uneven deposition of Li ions (Figure 4e,f). [42,43] To further confirm the dendrite-suppressing capability of the three solid electrolytes, lithium anodes after 1100 h cycle at 0.4 mA cm -2 was directly investigated by SEM images. Figure S15a,b (Supporting Information) shows numerous loose and porous "dead Li" on the surface of lithium anodes assembled with pure PVDF and MOF powder-PVDF solid electrolytes, respectively, which were in good consistent with the results of Li plating/stripping in symmetric Li-Li batteries.…”

Interstitial M+ (M+ = Li+ or Sn4+) Doping at Interfacial BiVO4/WO3 to Promote Photoelectrochemical Hydrogen Production

“…33,38 The XPS of Li 1s shows only one peak at ∼ 53 eV, which could be attributed to the Li−O bond. 45,46 According to XPS analysis, the Li−BVO/WO photoelectrode contains 0.71 atom % of Li (Supporting Information, Figure S4b). To shed light on the charge carrier generation and transport, the optical properties were measured (Figure 4f).…”

“…Similarly, the binding energies of V 2p 1/2 and V 2p 3/2 are shifted from 158.79 and 164.08 eV for the BVO/WO heterostructure to 158.46 and 163.77 eV for the Li-doped BVO/WO and 158.54 and 163.82 eV for the Sn-doped BVO/WO, respectively. From XPS analysis, the negative shift in binding energy indicates interstitial Li- or Sn-doping in BVO/WO because of the donor effect of high electronegative elements adding excessive electrons to the BVO conduction band. , The XPS of Li 1s shows only one peak at ∼ 53 eV, which could be attributed to the Li–O bond. , According to XPS analysis, the Li–BVO/WO photoelectrode contains 0.71 atom % of Li (Supporting Information, Figure S4b). To shed light on the charge carrier generation and transport, the optical properties were measured (Figure f).…”

Atomic and Molecular Layer Deposition of Alkali Metal Based Thin Films

“…Very recently, a Li-GL process was developed for coating Li-metal anodes . According to SEM image analysis, it yielded amorphous films at a very high average growth rate of ∼27 Å/c, much higher than any alkali-metal-based ALD/MLD process reported to date.…”