Supporting Information

Transcription

1 Supporting Information Carbon Nitride-Modified DefectiveTiO2 Spheres for Photocatalytic H2 Evolution and Pollutants Removal: Synergistic Effect and Mechanism Insight Chengzhang Zhu, Xiao Chen, Jian Ma, Cheng Gu, Qiming Xian,* Tingting Gong,* and Cheng Sun State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing , P. R. China *Corresponding authors: Qiming Xian, Tingting Gong Tel/Fax: ; address: The supporting information includes 8 pages, 6 figures and 3 tables. S1

2 (101) positive shift (004) (200) (105) (211) (204) Intensity (a.u.) -x CSs/-x (1) CSs/-x CSs/-x (6) CSs/-x (9) Theta (degree) Figure S1. XRD patterns of CSs/TiO2 composites in varying proportions, together with that of pristine TiO2 and TiO2 x. CSs CSs 1702 Transmittance (a.u.) C/-x C/-x -x -x CSs/-x CSs/-x -x -x Wavenumber (cm -1 ) Figure S2. FTIR spectra of CSs, TiO2, TiO2 x, CN, CSs/TiO2 x, TiO2 x and CSs/TiO2 x heterojunction. Figure S2 exhibited the FT-IR spectra of CSs, CN, TiO2, TiO2 x and TiO2 x-based composites. The strong bands at 1621 and 1702 cm 1 were associated with C=C and C=O vibrations, S2

3 respectively. 1 Furthermore, several peaks appeared in the range of cm 1 for bending vibrations of OH and C OH, implying the formation of numerous functional hydroxy groups on the CSs, which might be beneficial for loading TiO2 x NPs onto CSs. Generally, the bands of CN in the range of cm 1 correspond to the stretching vibrational modes of C-N heterocycles, and the broad band of TiO2 at cm 1 for bending vibrations of Ti O Ti. 2 Both typical bands of TiO2 x and CN still could be detected in the CSs/TiO2 x, while the characteristic peaks of CSs and CN (1636 cm 1 ) were very close and overlapped with each other. Notably, a moderate intensity band appeared at nearly 1045 cm 1 for the CSs/TiO2 x and CSs/TiO2 x, which could be attributed to Ti O C bonds. 3 Therefore, on the basis of the XRD and Raman results, as well as the above analysis, it could be confirmed that the CSs/TiO2 x were composed of CSs, TiO2 x NPs and CN NSs. Figure S3. SEM images of (a) g-c3n4 and (b) colloidal CSs. S3

4 Intensity (a.u.) C 1s C 1s C 1s N 1s Ti 2p Ti 2p Ti 2p O 1s O 1s O 1s CSs/-x CSs/-x C 1s N 1s Binding energy (ev) Figure S4. XPS survey scan spectrum of CN, TiO2, CSs/TiO2 x and CSs/TiO2 x. 1.0 Dark Light on (a) 1.0 Dark Light on (b) 0.8 Blank 0.8 Blank C/C x C/C x CSs/-x -x CSs/-x Time (min) CSs/-x -x CSs/-x Time (min) Figure S5. Photocatalytic degradation of CIP in the presence of different photocatalysts under: (a) simulated sunlight and (b) UV irradiation. S4

5 Figure S6. XRD patterns (a), XPS spectra (b) and SEM images of CSs/TiO2 x composite for the degradation of CIP before (c) and after (d) five cycles. Table S1. The Photocatalytic Hydrogen Production Efficiency of Different TiO2-Based Photocatalysts. Catalyst Light sources Reaction conditions HER Ref. (μmol/h/g) Mesoporous black AM 1.5 solar power 1 wt% of Pt co-catalyst, 7 [4] Methanol (20%) CdS/ Solar light-simulating source (Osram XBO 450W) Pt co-catalyst, Na 2S (4.8mM) and Na 2SO 3 (7.0 mm) 54 [5] C 3/ CQDs/P25 composites Au nanorod/ CdS-@ 300 W Xe lamp 420 nm 500 W halogen lamp λ = 450 nm 300 W Xe arc lamp <400 nm 300 W Xe lamp <400 nm Pt co-catalyst, TEOA (10%), 0.5wt% of H 2PtCl [6] Methanol (25 % ) 10 [7] Methanol (20 % ) 11.6 [8] 1 wt% of Pt co-catalyst, 0.5 M Na 2SO 3, 0.5 M Na 2S 75.2 [9] S5

6 Table S2. Pseudo-First-Order Rate Constant for CIP Photocatalytic Oxidation and HER over Different Samples. Photocatalyst k (min 1 ) R 2 HER (μmol/h/g) x CSs/ x x CSs/ x@cn CSs/ x@cn CSs/ x CSs/ x@cn Table S3. Comparison of the Photodegradation Activity Catalyst Light sources Catalyst Pollutant Rate constant Ref. amount CSs/ x@ UV lamp 50 mg CIP min -1 This work nanoparticles on montmorillonite UV lamp 0.1 g/l CIP min -1 [10] / Visible light 50 mg CIP min -1 [11] polymeric crystalline Ag/ Ag/N- 300 W Xenon lamp >420 nm Simulated visible light 350 W Xenon arc lamp 25 mg 2,4,6-TCP min -1 [12] 0.2 g MO min -1 [13] 0.05 g CIP min -1 [14] Pt-fullerene/ Visible lamp 0.05 g MO min -1 [15] S6

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