Supplementary Information
C3N4-H5PMo10V2O40: a dual-catalysis system for reductant-free
aerobic oxidation of benzene to phenol
Zhouyang Long, Yu Zhou, Guojian Chen, Weilin Ge, Jun Wang*
State Key Laboratory of Materials-Oriented Chemical Engineering, College of
Chemistry and Chemical Engineering, Nanjing University of Technology, Nanjing,
Jiangsu 210009, P. R. China
* Corresponding author, E-mail: junwang@njut.edu.cn
Recovering of PMoV2 from O2-insufficient reaction
To a 100 mL stainless autoclave equipped with a magnetic stir bar was placed
0.1 g C3N4(580), 0.4 g PMoV2, 4.0 mL benzene and 25 mL of the aqueous solution of
acetic acid (50 vol%). The system was charged with 1.5 MPa air (the O2 pressure was
about 0.3 MPa) at room temperature before the reaction was conducted at 140 oC for
10 h to minimize the amount of left O2 in the autoclave. After the reaction, the
reaction mixture was centrifuged and the solid C3N4 was separated. Water was added
into the left liquid phase followed by extraction with isopropyl ether. The combined
aqueous extracts were filtered and aqueous solution of Cs2CO3 was added to
precipitate the PMoV2 in the form of CsPMoV2.
Intensity(a.u.)
b
a
10
20
30
2 Theta (degree)
40
50
Supplementary Figure S1. XRD pattern of (a) fresh C3N4(580) and (b) recycled
C3N4(580).
The XRD pattern of the as-synthesized C3N4 is shown in Figure S1a. The
as-prepared C3N4(580) has surface areas (SBET) of 8.4 m2 g-1.The elemental analysis
for the prepared C3N4(580) showed 35.09% for the weight percentage of C, 61.97%
for N, 1.67% for H. Via elemental analysis, the mean C/N molar ratio was 0.66,
which was similar with the previous report
S1
. The elemental analysis for the last
recovered C3N4(580) (Fig. S1 (b)) was 46.94% for the weight percentage of C,
31.13% for N, 2.42% for H.
50
3
-1
Quantity Adsorbed (cm g , STP)
60
40
30
20
10
0
0.0
0.2
0.4
0.6
0.8
Relative Pressure (P/P0)
1.0
Supplementary Figure S2. Nitrogen gas adsorption isotherms for C3N4(580).
1164
962
869
786
Transmittence (%)
a
1080
b
982
888
802
3500
3000
2000
1500
1000
-1
Wavenumbers (cm )
Supplementary Figure S3. FT-IR spectra of (a) PMo and (b) PW.
1060
Transmittence (%)
a
963
860
791
b
c
d
3500
3000
2000
1500
1000
-1
Wavenumbers (cm )
Supplementary Figure S4. FT-IR spectra of (a) PMoV2, (b) CsPMoV2, (c) recovered
PMoV2 in the form of CsPMoV2 from the reaction of Table 1, entry 5 and (d)
recovered PMoV2 in the form of CsPMoV2 from the reaction with insufficient O2.
The FT-IR spectrum for PMoV2 is presented in Figure S4a. PMoV2 gave four
characteristic infrared bands for Keggin structure at 1,060, 963, 860 and 791 cm-1 42.
Supplementary Figure S5. SEM image of CsPMoV2.
12
(A)
14
Yield of phenol (%)
10
Yield of phenol (%)
(B)
12
8
6
4
2
10
8
6
4
2
0
0
20
40
60
80
0
0.00
100
0.05
0.10
Concentration of HAc (V/V%)
14
(C)
14
10
8
6
4
2
0.25
0.30
LiOAc
NaOAc
10
8
6
4
2
0
0.0
0.1
0.2
0.3
0.4
0
0.5
0.0
Amount of PMoV2 (g)
(E)
14
Yield of phenol (%)
10
8
6
4
0.4
0.6
Amount of LiOAc (g)
0.8
1.0
(F)
10
8
6
4
2
2
0
115
0.2
12
12
Yield of phenol (%)
0.20
(D)
12
Yield of phenol (%)
Yield of phenol (%)
12
14
0.15
Amount of C3N4 (g)
120
125
130
Temperature oC
135
140
0
0.5
1.0
1.5
2.0
Oxygen pressure (MPa)
2.5
14 (G)
Yield of phenol (%)
12
10
8
6
4
2
0
2.0
2.5
3.0
3.5
4.0
4.5
5.0
Reaction Time (h)
Supplementary Figure S6. Effects of reaction parameters on the yield of phenol.
(A) Effect of concentration of acetic acid on the yield of phenol. Reaction conditions:
4 mL benzene, 0.2 g C3N4(580),0.4 g PMoV2, 25 mL solvent, 0.6 g LiOAc, 2.0 MPa
O2, 130 oC, 4.5 h.
(B) Effect of amount of C3N4(580) on the yield of phenol. Reaction conditions: 4 mL
benzene, 25 mL aqueous solution containing 50 vol% acetic acid ,0.4 g PMoV2,0.6 g
LiOAc, 2.0 MPa O2, 130 oC, 4.5 h.
(C) Effect of amount of PMoV2 on the yield of phenol. Reaction conditions: 4 mL
benzene, 0.1 g C3N4(580), 25 mL aqueous solution containing 50 vol% acetic acid ,
0.6 g LiOAc, 2.0 MPa O2, 130 oC, 4.5.
(D) Effect of amount of LiOAc on the yield of phenol. Reaction conditions: 4 mL
benzene, 0.1 g C3N4(580), 0.4 g PMoV2, 25mL aqueous solution containing 50 vol%
acetic acid, 2.0 MPa O2, 130 oC, 4.5 h. If 0.6 g LiOAc was replaced with 0.6 g
NaOAc, the phenol yield is 11.4%.
(E) Effect of reaction temperature on the yield of phenol Reaction conditions: 4 mL
benzene, 0.1 g C3N4(580), 0.4 g PMoV2, 25 mL aqueous solution containing 50 vol%
acetic acid , 0.6 g LiOAc, 2.0 MPa O2, 4.5 h.
(F) Effect of oxygen pressure on the yield of phenol Reaction conditions: 4 mL
benzene, 0.1 g C3N4(580), 0.4 g PMoV2, 25 mL aqueous solution containing 50 vol%
acetic acid , 0.6 g LiOAc, 130 oC, 4.5 h.
(G) Effect of the reaction time on the phenol yield Reaction conditions: 4 mL benzene,
0.1 g C3N4(580), 0.4 g PMoV2, 25 mL aqueous solution containing 50 vol% acetic
acid , 0.6 g LiOAc, 2.0 MPa O2, 130 oC,
Supplementary Table S1. PMoV2 and CsPMoV2 catalytic performence for direct
hydroxylation of benzene to phenol with O2 in the presence of ascorbic acid. Reaction
conditions: Catalyst 0.2 g; ascorbic acid 0.6 g; aqueous solution containing 50 vol%
acetic acid 25 mL; 100 ℃; O2 2.0 MPa; 10 h.
Entry
Catalyst
Solubility in reaction
Yield of phenol (%)
1
PMoV2
Soluble
11.7
2
CsPMoV2
Insoluble
11.2
Supplementary Table S2. Aerobic oxidation of toluene over various catalysts.
Reaction conditions: C3N4(580) 0.1 g; PMoV2 0.4 g; toluene 4 mL; aqueous solution
containing 50 vol% acetic acid 25 mL; O2 2.0 MPa; 130 oC; 4.5 h. Yields of products
were determined by gas chromatography (GC).
Yield of products (%)
Entry
Catalyst
benzaldehyde
benzyl alcohol
cresols
1
C3N4(580)
0
0
0
2
PMoV2
7.7
1.4
0
3
C3N4-PMoV2
4.0
0.7
0.4
Supplementary References
S1. Ansari, M.B., Min, B.H., Mo, Y.H. & Park, S.E. CO2 activation and promotional
effect in the oxidation of cyclic olefins over mesoporous carbon nitrides. Green
Chem. 13, 1416-1421 (2011).