UV-radiation inducing strategy to tune fluorinated carbon bonds delivering the high-rate Li/CFx primary batteries

Pushing capacities and energy densities beyond theoretical limits of lithium primary batteries using active CFx nanocapsules with x > 1

“…1f). 24,35 The I D / I G ratio of 1.61 indicates partial-graphitization of CNCs with a large number of defects, while fluorination broke the sp 2 -hybridized bonds into the sp 3 -hybridized system to generate a C–F structure, confirmed by an enhanced D-band with a slight shift at ∼1375 cm −1 and a disappeared G-band in the Raman spectrum of CFNCs (Fig. 1g).…”

“…38 The absorption peak of CFNCs-325 at ∼1643 cm −1 is indexed to the stretching vibration of in-plane CC bonds, while a much weaker absorption peak of CFNC-360 at ∼1650 cm −1 is observed. 24…”

“…38 The absorption peak of CFNCs-325 at ∼1643 cm −1 is indexed to the stretching vibration of in-plane CvC bonds, while a much weaker absorption peak of CFNC-360 at ∼1650 cm −1 is observed. 24 To reveal the thermal stability of CFNCs and the F/C ratio, a thermogravimetric (TG) analysis was performed which shows three-stage weight loss (Fig. 2a).…”

“…23 Recent discoveries also found that introducing a high concentration of semi-ionic bonds improves the energy density of CF x batteries. 24 However, the working conversion reaction of CF x as well as the generation and chemical stability of semi-ionic bonds are not well-understood to harvest the full potential of these materials in realizing sustainable energy densities for longer operations. 25,26 To achieve high-performance CF x materials certain materials characteristics need to be tuned in such a way that the resulting materials exhibit higher conductivity, larger semi-ionic bonds, and easy diffusion of lithium ions.…”

Advanced Lithium Primary Batteries: Key Materials, Research Progresses and Challenges

“…As depicted in Figure 3b, using the inducing strategy of the UV-radiation, not only with the increase of relative proportion of semi-ionic CÀ F, but also the ratio of the inert CÀ F 2 and inactive CÀ F 3 can be reduced. [28] In addition, after the modification of UV-radiation, the CF x has more channels with multi-level, which is beneficial for the electrolyte infiltration and charge transmission. With the technology of UV-radiation, the rate capability of CF x get greatly improved.…”