Synthesis of ZnIn₂S₄@Co₃S₄ particles derived from ZIF-67 for photocatalytic hydrogen production

Abstract

Appropriate morphology and structure can provide more charge adsorption sites which contribute to high catalytic activity, ZnIn2S4 with the coupling amount of 5% Co3S4 displays superior performance in the photocatalytic hydrogen evolution reactions.

Efficient H2 evolution on Co3S4/Zn0.5Cd0.5S nanocomposites by photocatalytic synergistic reaction

“…45,46 As shown in Fig. 3e, there are six characteristic peaks of Co element, 39 and the peaks at 779.4 (Co 3+ 2p 3/2 ) and 794.0 eV (Co 3+ 2p 1/2 ) are attributed to Co 3+ . Meanwhile, the other two peaks are ascribed to Co 2+ at 781.7 (Co 2+ 2p 3/2 ) and 797.9 eV (Co 2+ 2p 1/2 ).…”

“…The hollow Co 3 S 4 polyhedron was synthesized from ZIF-67 according to a previous report. 39 Firstly, ZIF-67 with a polyhedron structure (Fig. S1 †) was synthesized in three steps: (1) 2-methylimidazole (96.00 mmol) was dissolved in 60 mL of methanol; (2) Co(NO 3 ) 2 •6H 2 O (12.00 mmol) in 60 mL of metha-nol was quickly dispersed into the above solution, and the mixture was kept for 24 h at room temperature after stirring vigorously for 10 min; (3) a purple precipitate was obtained by centrifuging, washing and drying in a vacuum oven at 60 °C for 12 h. Then, 0.68 g of ZIF-67 was dispersed in absolute ethanol (40 mL) by ultrasound for 20 min.…”

“…In the M-S plots, the slopes of the linear region for ZCS and Co 3 S 4 are positive, indicating that the samples are n-type semiconductors. 31,37,39 According to the intercept of the X-axis tangent (Fig. 9b and c), the flat band potentials (E fb ) of ZCS and Co 3 S 4 were estimated to be −0.71 and 0.16 eV (vs. RHE), respectively.…”

“…Depositing cocatalysts on the main catalyst is an effective way to improve the activity of the catalyst by accelerating the separation of electrons and holes. Co-based compounds, such as Co 3 O 4 , 38 Co 3 S 4 , 39,40 Co 9 S 8 , 41 and CoP, 42,43 are used as cocatalysts for efficient H 2 production. Among them, the energy band position of Co 3 S 4 is well-matched with that of Zn x Cd 1−x S, with the separation of photogenerated charge carriers promoted, which facilitates the photocatalytic performance of H 2 production.…”

Inexpensive and Abundant Layered Co-Based Composite Photocatalysts for Hydrogen Production and Theoretical Calculations

“…The peaks at binding energies of 795.1 and 780.5 eV are the Co 2p 1/2 and Co 2p 3/2 orbitals of Co 2+ , while the peaks at binding energies of 794.2 and 779.6 eV are the Co 2p 1/2 and Co 2p 3/2 orbitals of Co 3+ of the CS/ ZCS heterojunction,34 as shown in Figure4e. Movement of the XPS peaks of the Co and S elements proves that formation of the CS/ZCS heterojunction resulted in the transfer of electrons from CS to ZCS, so the binding energy of each element was decreased and increased for ZCS and CS, respectively 33,35. 3.3.…”