2.2.3. WO3 and H2S Synthesis of WS2 Nanomaterials

A comparison of the XRD profiles of the commercial 2H-WS2 and the present IF-WS2 samples is shown in Figure S9. Both patterns showed peaks at very similar positions. The peaks of IF-WS2 were assigned according to 2H-WS2 (JCPDS No. 84-1398), as no standard XRD pattern is available for IF-WS2 [1]. These are the typical peaks at 2ș angles at: 14.364 (002), 28.959 (004), 32.769 (100), 33.587 (101), 35.943 (102), 39.599 (103), 44.055 (006), 44.289 (104), 49.798 (105), 55.977 (106), 57.495 (110), 60.010 (008), 60.573 (112), 62.746 (107), 69.169 (201), 70.080 (108), 72.957(203), and 76.040(116). For the 2H-WS2, all peaks are very sharp, indicating a well-crystallized and standard 2H structure. Its (002) is the strongest peak, followed by (103) as the second strongest. Compared with 2H-WS2, the (002) peak of IF-WS2 is left-shifted, indicating a lattice expansion of the (002) layers due to stains in the curved closed-cage layers [2]. The (103) and (105) peaks are broadened, attributing to the ultra-low dimensions. Whilst the (002) remains as the strongest peak, two peaks representing (100) and (101) have merged into one exhibiting the second highest intensity. The (006) and (104) peaks also merged, at around 44.1 degree. The (102) peak at around 35.9 degree was not detected in the IF-WS2 profile. The small peaks appeared at 23-25 degree in the IF-WS2 pattern were assigned to WO*x*, which must exist as the residue core of some IF-WS2 particles.

**Figure S9.** XRD profiles of commercial 2H-WS2 and currently synthesised IF-WS2.
