SUPPORTING INFORMATION

Transcription

1 SUPPORTING INFORMATION Carbon Nitride Aromatic Diimide Graphene Nanohybrids: Metal-Free Photocatalysts for Solar-to-Hydrogen Peroxide Energy Conversion with.2% Efficiency Yusuke Kofuji, Yuki Isobe, Yasuhiro Shiraishi,*,, Hirokatsu Sakamoto, Shunsuke Tanaka, Satoshi Ichikawa, and Takayuki Hirai Research Center for Solar Energy Chemistry, and Division of Chemical Engineering, Graduate School of Engineering Science, Osaka University, Toyonaka , Japan Precursory Research for Embryonic Science and Technology (PRESTO), Japan Science and Technology Agency (JST), Saitama , Japan Department of Chemical, Energy and Environmental Engineering, Kansai University, Suita , Japan Institute for NanoScience Design, Osaka University, Toyonaka , Japan CONTENTS page Figure S1. XRD patterns for respective catalysts.... S2 Figure S2. XPS chart for N1s levels of respective catalysts... S3 Figure S3. Diffuse reflectance UV-vis spectra of respective catalysts... S4 Figure S4. Results of photocatalytic O2 formation with AgNO3... S5 Figure S5. Results of photocatalytic H2O2 formation with 2-PrOH... S5 Figure S6. Linear-sweep voltammograms of respective catalysts measured on RDE... S6 Figure S7. Results of photocatalytic H2O2 formation with water containing H2O2... S7 Table S1. Effect of the procedure on the photocatalytic H2O2 production... S8 S1

2 x =.2 x =.5 x = θ / Figure S1. XRD patterns for g-c3n4/pdi and g-c3n4/pdi/rgox catalysts. S2

3 x = Binding energy / ev Binding energy / ev x =.2 x = Binding energy / ev Binding energy / ev Figure S2. XPS charts (N1s level) of g-c3n4/pdi and g-c3n4/pdi/rgox catalysts. Black line is the observed chart, and gray line is sum of the components. Integration of respective components N N N N N/N melem:pdi [a] g-c3n4/pdi 62.9% 1.5% 21.4% 5.2% 6. 49:51 g-c3n4/pdi/rgo % 1.5% 2.7% 5.6% 6. 5:5 g-c3n4/pdi/rgo % 1.8% 21.3% 4.8% 5.9 5:5 g-c3n4/pdi/rgo % 1.5% 21.1% 5.% 6. 5:5 [a] The mole fractions of melem and PDI components were calculated using the following equation. melem PDI = (N)/6 (N)/6 + (N)/2 (N)/2 (N)/6 + (N)/2 S3

4 4 F(R ) 3 2 x = 1 x =.5 x =.2 x =.1 x =.5 x = Wavelength / nm /rgo.5 (hvf(r )) ev hν / ev Figure S3. Diffuse-reflectance UV-vis spectra of respective catalysts and result of bandgap determination on g-c3n4/pdi/rgo.5. S4

5 1 /rgo.5 O 2 formed / µmol Figure S4. Time-dependent change in the amounts of O2 formed during photoreaction with g-c3n4/pdi and g-c3n4/pdi/rgo.5 catalysts in water with.1 M AgNO3 under Ar atmosphere. t / h 8 1 H 2 O 2 formed / µmol /rgo.5 5 H 2 O 2 selectivity / % t / h Figure S5. Time-dependent change in the amounts of H2O2 formed and the H2O2 selectivity during photoreaction with g-c3n4/pdi and g-c3n4/pdi/rgo.5 catalysts in a 2-PrOH/O2 system. H2O2 selectivity (%) = [H2O2] / ([acetone] + [CO2]/3) 1. S5

6 a Current density / ma cm Rotating speed 4 rpm 8 rpm 12 rpm 16 rpm E / V vs Ag/AgCl bcurrent density / ma cm 2 Current density / ma cm 2 c 1 2 /rgo E / V vs Ag/AgCl Rotating speed 4 rpm 8 rpm 12 rpm 16 rpm 1 2 rgo E / V vs Ag/AgCl Rotating speed 4 rpm 8 rpm 12 rpm 16 rpm Figure S6. Linear-sweep voltammograms of (a) g-c3n4/pdi, (b) g-c3n4/pdi/rgo, (c) rgo measured on RDE at different rotating speeds. S6

7 12 1 λ> 42 nm dark H 2 O 2 formed / µmol λ> 42 nm t / h Figure S7. Time-dependent change in the amounts of H2O2 measured by stirring pure water or water containing ca. 1 µmol H2O2 in the dark or under visible light irradiation with g-c3n4/pdi/rgo.5. Reaction conditions: solution (3 ml), catalyst (5 mg), O2 (1 atm), λ >42 nm (Xe lamp, light intensity at 42 5 nm: 43.3 W m 2 ). S7

8 Table S1. Effect of the procedure for catalyst preparation on the photocatalytic H2O2 production. [a] run catalyst procedure picture H2O2 / µmol 1 (i) stirring of melem and GO (ii) hydrothermal treatment (iii) calcination with PMDA (identical to Scheme 2 in the manuscript) (i) stirring of melem and GO (ii) calcination with PMDA g-c3n4/pdi/rgo.5 (i) stirring of g-c3n4/pdi and GO (ii) hydrothermal treatment (i) hydrothermal treatment of GO (ii) stirring of melem and rgo (iii) calcination with PMDA (i) hydrothermal treatment of GO (ii) stirring of g-c3n4/pdi and rgo g-c3n4/pdi calcination of melem with PMDA 14.9 [a] Photoreaction conditions: water (3 ml), catalyst (5 mg), O2 (1 atm), λ >42 nm (Xe lamp, light intensity at 42 5 nm: 43.3 W m 2 ). S8