C–S bond induced ultrafine SnS₂ dot/porous g-C₃N₄ sheet 0D/2D heterojunction: synthesis and photocatalytic mechanism investigation

Abstract

The construction of novel heterojunctions is precisely deemed to be an effective strategy to facilitate photo-generated carrier separation and boost charge utilization efficiency, leading to much enhanced photocatalytic activities. Herein, in situ of growing ultrafine SnS nanoparticles on a porous g-CN sheet (SnS/g-CN) 0D/2D heterojunction was achieved via a low-temperature solvothermal process. Combined with various characterization techniques, it is revealed that SnS dots with a diameter of 3 nm distribute evenly on the surface of the g-CN substrate with strong C-S bonds. The photocatalytic activities are evaluated by the degradation of Rhodamine B (RhB) under visible light irradiation, showing a much enhanced photodegradation efficiency of 96.8% over 105 min irradiation and an enhanced reaction rate constant (k = 3.3% min, 8.25 and 8.05 times that of pure g-CN and SnS). The improved photocatalytic activities could be ascribed to the efficient electron-hole separation of porous g-CN, which is caused by the ultrafine SnS dots linked with the g-CN substrate through C-S bonds. Therefore, the recombination efficiency is decreased. In addition, reactive active species trapping experiments prove that the superoxide radical (˙O) and holes (h) are the main active species in this photocatalytic system. The photodegradation mechanism of the SnS/g-CN heterojunction is analyzed and demonstrated in detail.

Dual Functions of CO2 Molecular Activation and 4f Levels as Electron Transport Bridge in Dysprosium Single Atom Composite Photocatalysts with Enhanced Visible‐Light Photoactivities

“…Therefore, the use of photocatalysts to achieve an efficient conversion of CO 2 into green energy under the irradiation of clean solar energy is a popular choice of effective means. [16][17][18][19][20][21][22][23][24][25][26] It is well known that the construction of excellent photocatalytic materials is a necessary means to improve photocatalytic performance. [27][28][29][30][31] Among the photocatalytic materials reported, the bandgap of graphite carbon nitride (g-C 3 N 4 ) is ≈2.7 eV, and the conduction band (CB) level is relatively negative, which promotes the reduction capability of photogenerated electrons.…”

Interfaces of graphitic carbon nitride-based composite photocatalysts

“…156 Tin disulfide spontaneously grows into a typical two-dimensional CdI 2 -type layered structure if no limitation is introduced to the crystal nucleation process in the liquid system. 76 In a practical experiment, g-C 3 N 4 decorated with zero-dimensional SnS 2 nanodots, 8,76 two-dimensional SnS 2 nano-sheets [165][166][167] and threedimensional SnS 2 nano-flowers 168,169 have been fabricated by considering the selection of reactants, the choice of reaction solvents and the design of reaction routes. In one of our previous reports, 76 we firstly dispersed SnCl 4 •5H 2 O and g-C 3 N 4 into 25 mL anhydrous ethanol with sonication assistance, then added thioacetamide as a sulfur-source to the mixture after achieving the surface adsorption of Sn 4+ ions on the surface of g-C 3 N 4 .…”

“…76 In a practical experiment, g-C 3 N 4 decorated with zero-dimensional SnS 2 nanodots, 8,76 two-dimensional SnS 2 nano-sheets [165][166][167] and threedimensional SnS 2 nano-flowers 168,169 have been fabricated by considering the selection of reactants, the choice of reaction solvents and the design of reaction routes. In one of our previous reports, 76 we firstly dispersed SnCl 4 •5H 2 O and g-C 3 N 4 into 25 mL anhydrous ethanol with sonication assistance, then added thioacetamide as a sulfur-source to the mixture after achieving the surface adsorption of Sn 4+ ions on the surface of g-C 3 N 4 . Finally, the whole mixture was subjected to a solvothermal reaction at low temperature (100 °C) for 10 h, obtaining the ultrafine SnS 2 dot/g-C 3 N 4 sheet composite photocatalyst.…”

“…To date, almost all the known methods for fabricate g-C 3 N 4 are related to the direct thermal condensation of nitrogen-containing organic precursors (Fig. 2a) under a given solid condition, with one or mixtures of the following: melamine, [63][64][65][66][67] cyanamide, 68 dicyandiamide, [69][70][71][72] urea [73][74][75][76] and thiourea, 48,77,78 where the reactive temperature ranges from 450 °C to 650 °C. 41 During the thermal polymerization process, parts of the carbon and nitrogen elements are retained in the matrixes and exist as carbon nitride, while other parts are emitted in the form of ammonia, carbon oxides, hydrone, and so on.…”

Rational Construction of Z‐Scheme CuInS2/Au/g‐C3N4 Heterostructure: Experimental Results and Theoretical Calculation

“…[13][14][15][16] In particular, the heterojunction of p-type sulfide with n-type g-C 3 N 4 has been intensively investigated due to the high suitable band matching of each other and the narrow band gap of p-type sulfide, which engages excellent absorption of solar energy. [17] For instance, MoS 2 /g-C 3 N 4 , [4] SnS 2 /g-C 3 N 4 , [18] ZnIn 2 S 4 /g-C 3 N 4 , [19][20][21] MgIn 2 S 4 /g-C 3 N 4 , [22] CdIn 2 S 4 /g-C 3 N 4 , [23] CaIn 2 S 4 /g-C 3 N 4 , [24] have been developed. Notably, CuInS 2 with a band gap of 1.5 eV has driven more attention due to its excellent visible light response ability, suitable band gap, exceptional radiation hardness and environmentally nontoxicity.…”