ENV IRONM ENTAL CHEM ISTRY

Transcription

1 ENV IRONM ENTAL CHEM ISTRY Vol. 29, No. 3 May 2010 Sm 3 + /TiO 2 CO 2 H 2 O CH 3 O H (1,, ; 2,, ) Sm 3 + /TiO 2, X (XRD ) ( TEM ) (UV2V is) ( IR), CO 2 H 2 O CH 3 OH.,,, 2 2,,.,,,,. CO 2 CH 3 OH,, CO 2,,. [ 1 5 ], Sm 3 + /TiO 2, CO 2 H 2 O CH 3 OH, X (XRD) ( TEM ) (UV2V is) ( IR ), :, A, 30m in B. B 1 s - 1 A,, 2 3d,, 100 2h, 3h,. Sm / Ti 015% 1% 115% 210% Sm 3 + /TiO ( s2e2c) : 015g C 19 H 42 B rn, 15m l, 20m in, A. 5m l 25m l,, 1h B. A 25m l, 20m in, C. B C, 18h,.,, 2h, x (mol) % Sm /TiO 2 ( s2e2c) XRD Bede XRD D I SYSTEM X2, Cu K, 20 80, Scherrer D = 0189 / ( cos ), X, , : ; E2mail: cxyywf@1261com

2 482 29,. TEM H2600, 20kV, 100mA,,. UV2V is U23310, nm. ( FT2IR) N icolet 5700, 32, 4 cm , 1g l mol l - 1 NaOH, 30 m in,, CO 2 30m in, NaOH CO 2 ;., CO 2 (365nm )., SP22000B % Sm 3 + /TiO 2 XRD, , 37188, (101), (004), (200). TiO 2, , TiO 2,.,,,. XRD. 2 = 25138, , 916nm 1111nm 1211nm 1615nm,,,, XRD,, 2 2 (101) 2,,, Sm. (101),,. XRD Sm, XRD (101) 2 TiO 2, Ti 4 + ; % Sm 3 + /TiO 2 XRD a. 450, b. 500 c. 600, d TiO 2 110% Sm 3 + /TiO 2 XRD a1 1% Sm 3 + /TiO 2 ( s2e2c) b1 1% Sm 3 + /TiO 2 c1 TiO 2 ( s2e2c) d1 TiO 2 F ig11 XRD patterns of 110% Sm 3 + /TiO 2 calcined at different temperatures F ig12 XRD patterns of different TiO 2 110% Sm 3 + /TiO 2 catalysts and

3 3 : Sm 3 + /TiO 2 CO 2 H 2 O CH 3 OH 483 1, TiO 2,.,, [ 6 ] TiO 2 TiO 2. 1 TiO 2 Sm 3 + /TiO 2 Table 1 Particle size of TiO 2 and110% Sm 3 + /TiO 2 catalysts TiO 2 110% Sm 3 + /TiO 2 TiO 2 110% Sm 3 + /TiO 2 d / nm , 400nm,, nm, Sm, nm, TiO 2 [ 7 ],. 4 TiO 2 110% Sm 3 + /TiO 2 IR. 4, 3400cm - 1 Ti OH, OH,,, 110% Sm 3 + /TiO 2 ( s2e2c). Sm,, ;,. 3 UV2V is a1tio 2, b11% Sm 3 + /TiO 2, c11% Sm 3 + /TiO 2 ( s2e2c) F ig13 UV2V is spectra of different catalysts 4 TiO 2 110% Sm 3 + /TiO 2 a1tio 2, b1110% Sm 3 + /TiO 2 ( s2e2c), c1110% Sm 3 + /TiO 2 F ig14 IR spectra of TiO 2 and 110% Sm 3 + /TiO 2 catalyst 212 1% Sm 3 + /TiO 2 1% Sm 3 + /TiO 2 ( s2e2c), 5. 5, 2 2,,,,,,,,,. 1 10nm,, [ 8 ], 2, ,,., Sm /Ti 1%,,,

4 Sm 3 + ( Ti nm, Sm nm),, ;,, Sm 3 +,, TiO 2, 2,,. 5 F ig15 Methanol yield of different catalysts 6 F ig16 Effect of Sm 3 + loading amount on methanol yield 214 Sm 3 + TiO 2, Ti 4 + O 2 -, Sm 3 + Ti 4 +, TiO 2,,, Sm 3 +, O 22.,,, Sm 3 +,,., Sm 3 + /Sm v [ 9 ], Sm 3 + Sm 2 +,, TiO 2. : 3 TiO 2 + hvϖ e - + h + + TiO 2 2H 2 O + 4h + ϖ O 2 + 4H + H + + e - ϖ H CO 2 + e - ϖ CO - 2 CO H + h + ϖ CH 3 OH + H 2 O Sm 3 + TiO 2,, Sm 3 +, 2, ;, 2 2,,,,, Sm 3 + 1%. [ 1 ] Yamashita H, N ishiguchi H, Kamada N et al., Photocatalytic Reduction of CO 2 with H 2 O on TiO 2 and Cu /TiO 2 Catalysts [ J ] 1 R es1chem 1Interm ed1, 1994, [ 2 ] Keita Ikeue, Masakazu Anpo, Characterization of Self2Standing Ti2Containing Porous Silica Thin Film s and Their Reactivity for the Photocatalytic Reduction of CO 2 with H 2 O [ J ] 1 Catalysis Today, 2002, [ 3 ] Tseng I2H siang, W u Jeffrey C S, Chou H sin2ying, Effects of Sol2Gel Procedures on the Photocatalysis of Cu /TiO 2 in CO 2 Photoreduc2 tion1 [ J ] 1Journal of Catalysis, 2004, [ 4 ],,, Cu /WO 3 2N io [ J ] 1, 2003,

5 3 : Sm 3 + /TiO 2 CO 2 H 2 O CH 3 OH 485 [ 5 ] Guoqing Guan, Tetsuya Kida, Reduction of Carbon D ioxide with W ater under Concentrated Sunlight U sing Photocatalyst Combined with Fe2Based Catalyst [ J ] 1 A pplied Catalysis A: General, 2003, [ 6 ],,, TiO 2 1 [ J ] 1, 2003, [ 7 ] Yu J C, Yu J G, Ho W K et al 1, Effects of F2Dop ing on the Photocatalytic Activity and M icrostructures of Nanocrystalline TiO 2 Ponders [ J ] 1 Chem istry of M aterials, 2002, 14 (9) [ 8 ],,, [M ] 1 :, 2001, 6 13 [ 9 ], [M ], :, 1997 Sm 3 + /T io 2 CATALY ZED PHO TO 2SY NTHES IS O F M ETHANOL FROM CARBO N D IO X ID E AND W ATER CHAO X ian2yu 1 ZHAN G N ing 2 J IAN L i2juan 2 (1 Salt Lake Department of Chem istry Institute, Q inghai University, Xining, , China; 2 Chem istry Department of Nanchang University, Nanchang, , China) ABSTRACT Photocatalytical reduction of carbon dioxide to methanol in an aqueous solution was investigated1 The photocatalysts, Sm 3 + doped TiO 2, was p repared by sol2gel method or sol2 emulsion2combustion method1 The catalyst was characterized by X2ray powder diffractometer ( XRD ) TEM UV2V is diffuse reflection spectra and IR analysis1 The effect of p reparation m ethods and quantity of ions dopant on the activity of the catalyst, was investigated1 The dop ing increased the specific surface area of the catalyst, and made the particles more uniform1the sol2emulsion2com bustion m ethod p roduced catylets w ith smaller particle size, larger specific surface area and higher photocatalytic activity than the sol2gel method1 Keywords: photocatalysis, TiO 2, lanthanide dop ing, Sm 3 +, methanol.