Table 1 Comparison of the intensity fraction p110 and the Lotgering degree of orientation f110 as well as the possible texture fraction fv(110) of the Li electrodeposits estimated from the intensity ratio I200/I211/I110 in their θ−2θ scans

From: Critical evaluation of (110) texture in lithium electrodeposits on isotropic Cu polycrystals

Sample

Data reported in Zhao’s paper

f110

Possible fv(110) values estimated within ΔΩ

D (μm)

t (μm)

I200/I211/I110

p110

ΔψΔω ≈ 6° × 1.5°

ψmax = 5°

ψmax = 10°

5 mAh Li deposited

2.7

35

61/71/1000

88.3%

71.6%

1.10%

11.1%

34.7%

10 mAh Li deposited

4.8

56

27/79/1000

90.4%

76.7%

1.37%

13.5%

39.9%

20 mAh Li deposited

6.4

108

25/72/1000

91.2%

78.6%

1.49%

14.5%

41.9%

Li powder

—

—

30/40/100

58.8%

—

0.21%

2.3%

9.12%

  1. The corresponding data for Li powder are listed for comparison and its I200/I211/I110 values are known from PDF #15-0401. The average surface grain size D of each Li deposit and its thickness t are also listed. The possible fv(110) values within different orientation spreads ΔΩ are estimated by using Eq. (2). The angle window of diffractometer ΔΩw = πΔψΔω/4, here Δψ and Δω in unit of radian are the diameters of angle window parallel and perpendicular to the diffraction plane, respectively12,13. The possible ΔψΔω value of ≈6° × 1.5° is a typical angle window of X-ray diffractometer with a conventional point detector. The spread range of (110) texture ΔΩ = 2π(1 − cosψmax), where ψmax is the maximum tilt deviation angle of (110) orientation. The ψmax is usually given to be 5° and it can be customized based on the requirement. The possible ψmax of 10° is large enough for quantifying the (110) texture of Li films because for Li powder the \({f}_{{{{{{\rm{v}}}}}}}^{*}\left(110\right)\) within the spread ΔΩ reaches a high value of 9.12%. Considering all the values of the interplane angles ∠{hkl}:(110) for cubic Li, we know that each Li crystallite with any (hkl) orientation has always a set of (110) lattice planes oriented with a tilt angle ψ of ≤30° or 45°. The orientation spread ΔΩ is an essential parameter in the quantitation of texture fraction fv(hkl) and thus the ψmax value customized needs be indicated when each fv(hkl) value is reported.
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