Fig 1

(a) Illustration of the synthesis processes for preparing the NiS2/T-MCS photocatalyst, (b) XRD patterns of pristine NiS2, T-MCS and the 8 wt% NiS2/T-MCS composite, Scanning Electron Microscopy (SEM) image of (c, d) pure T-MCS, NiS2, and (e) 8 wt% NiS2/T-MCS, (f) EDS of S, Mn, Cd, and Ni elements of 8 wt% NiS2/T-MCS."

Fig 2

TEM of (a–d) T-MCS and (e–h) 8 wt% NiS2/T-MCS, Water contact angles of (i) T-MCS, (j) NiS2 and (k) 8 wt% NiS2/T-MCS."

Fig 3

(a–d) High-resolution XPS spectra of Cd 3d, Mn 2p, Ni 2p, S 2p respectively in T-MCS, NiS2, and 8 wt% NiS2/T-MCS."

Fig 4

(a, b) Photocatalytic rH2 of the different materials, (c) Photocatalytic H2 production yield of the different materials, (d) The long-term test of H2 production over 8 wt% NiS2/T-MCS, (e) Wavelength-dependent AQY of photocatalytic H2 evolution over 8 wt% NiS2/T-MCS together with its UV-Vis DRS spectra, (f) The photo of H2 production of 8 wt% NiS2/T-MCS in H2S-saturated Na2S/Na2SO3 across 350–780 nm wavelength range, (g) Comparison of rH2 of different reaction solutions or catalysts."

Fig 5

(a) FTIR spectra of Na2S/Na2SO3 and H2S-saturated Na2S/Na2SO3 solution, (b) UV-Vis spectra of Na2S/Na2SO3 and H2S-saturated Na2S/Na2SO3 solution, (c) UV-Vis spectra of the solution after reacting 12 h, and (d) FTIR spectra of different samples and reaction time."

Fig 6

(a) I–t, (b) EIS, (c) Bode, and (d) LSV diagram of the materials, (e) the relation between current density and corresponding scan rates, (f) UV-Vis DRS spectra and (g) Tauc's energy bandgap plots of the different materials, (h, i) MS plots of WZ-MCS and ZB-MCS."

Fig 7

(a) Charges transfer mechanism over 8 wt% NiS2/T-MCS under illumination, (b) Illustration of overall transformation of H2S and Na2S/Na2SO3 over 8 wt% NiS2/T-MCS."