Supporting Information Carbon Nitride-Modified DefectiveTiO2 x@carbon 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 210023, P. R. China *Corresponding authors: Qiming Xian, Tingting Gong Tel/Fax: +86 25 89680259; E-mail address: xianqm@nju.edu.cn The supporting information includes 8 pages, 6 figures and 3 tables. S1
(101) positive shift (004) (200) (105) (211) (204) Intensity (a.u.) -x CSs/-x (1) CSs/-x CSs/-x (6) CSs/-x (9) 10 20 30 40 50 60 70 80 2-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 1624 1045 540 808 1636 1573 1409 1317 1240 3600 3000 2400 1800 1200 600 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
respectively. 1 Furthermore, several peaks appeared in the range of 1000-1300 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 1200 1650 cm 1 correspond to the stretching vibrational modes of C-N heterocycles, and the broad band of TiO2 at 500 750 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
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 0 150 300 450 600 750 900 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 0 0.6 -x C/C 0 0.6 -x 0.4 0.2 CSs/-x -x CSs/-x @CN-1 CSs/-x @CN-1.5 CSs/-x CSs/-x @CN-4 0.0-60 -40-20 0 20 40 60 80 100 120 Time (min) 0.4 0.2 CSs/-x -x CSs/-x @CN-1 CSs/-x @CN-1.5 CSs/-x CSs/-x @CN-4 0.0-60 -40-20 0 20 40 60 80 100 120 Time (min) Figure S5. Photocatalytic degradation of CIP in the presence of different photocatalysts under: (a) simulated sunlight and (b) UV irradiation. S4
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 68.7 [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
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) 0.00303 0.99218 0 x 0.00407 0.99501 26.3 0.00145 0.99124 7.5 CSs/ x 0.00669 0.99336 38.1 x 0.00934 0.99542 43.5 CSs/ x@cn-1 0.01027 0.99493 CSs/ x@cn-1.5 0.01302 0.99614 CSs/ x 0.01678 0.99379 103.9 CSs/ x@cn-4 0.01139 0.99726 Table S3. Comparison of the Photodegradation Activity Catalyst Light sources Catalyst Pollutant Rate constant Ref. amount CSs/ x@ UV lamp 50 mg CIP 0.01678 min -1 This work nanoparticles on montmorillonite UV lamp 0.1 g/l CIP 0.0069 min -1 [10] / Visible light 50 mg CIP 0.01185 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 0.0022 min -1 [12] 0.2 g MO 0.0130 min -1 [13] 0.05 g CIP 0.0163 min -1 [14] Pt-fullerene/ Visible lamp 0.05 g MO 0.00367 min -1 [15] S6
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