Photocatalytic CO2 Reduction Under Continuous Flow High-Purity Conditions: Quantitative Evaluation of CH4 Formation in the Steady-State

被引:60
作者
Dilla, Martin [1 ]
Schloegl, Robert [1 ,2 ]
Strunk, Jennifer [1 ,3 ]
机构
[1] Max Planck Inst Chem Energy Convers, Mulheim, Germany
[2] Max Planck Gesell, Fritz Haber Inst, Berlin, Germany
[3] Univ Duisburg Essen, Ctr Nanointegrat Duisburg Essen, Duisburg, Germany
关键词
carbon dioxide reduction; heterogeneous catalysis; high-purity reaction conditions; photocatalysis; titania; CARBON-DIOXIDE; TIO2; PHOTOCATALYSIS; SURFACE; H2O; TITANIUM; NANOPARTICLES; MECHANISMS; TIO2(110); DYNAMICS; OXIDES;
D O I
10.1002/cctc.201601218
中图分类号
O64 [物理化学(理论化学)、化学物理学];
学科分类号
070304 ; 081704 ;
摘要
In this study, the photocatalytic CO2 reduction on TiO2 P25 was investigated for the first time under high-purity continuous flow conditions with gas chromatographic (GC) online detection of CH4 as the main product. The thorough photocatalytic cleaning procedure in humid helium prior to all measurements was conducted under continuous flow too and we were able to monitor the decrease of carbonaceous contaminant concentration. On addition of CO2 to the feed under illumination, an increase in CH4 concentration was observed, which clearly follows the increase in CO2 concentration in the reactor. It was also demonstrated that CH4 formation ceases as soon as the lamp is switched off, providing clear evidence that the formation of CH4 from CO2 is a photoinduced process. It was shown that higher CO2 concentration accelerated CH4 formation under steady-state conditions up to a certain optimum. Higher CO2 concentrations lead to a decrease in CH4 formation. This observation is tentatively assigned to a limited availability of photogenerated charge carriers at the TiO2 surface, or a lack of suitable catalytically active sites. Traces of O-2 in the reactor completely hinder CH4 formation, implying that the lack of concomitant oxygen evolution observed in previous measurements on TiO2 is likely beneficial for the overall process. This study represents a first step towards performing true steady-state kinetic studies of photocatalytic CO2 reduction.
引用
收藏
页码:696 / 704
页数:9
相关论文
共 38 条
[1]   MECHANISM AND KINETIC CHARACTERISTICS OF THE ELECTROCHEMICAL REDUCTION OF CARBON-DIOXIDE IN MEDIA OF LOW PROTON AVAILABILITY [J].
AMATORE, C ;
SAVEANT, JM .
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 1981, 103 (17) :5021-5023
[2]   PHOTOCATALYTIC REDUCTION OF CO2 WITH H2O ON VARIOUS TITANIUM-OXIDE CATALYSTS [J].
ANPO, M ;
YAMASHITA, H ;
ICHIHASHI, Y ;
EHARA, S .
JOURNAL OF ELECTROANALYTICAL CHEMISTRY, 1995, 396 (1-2) :21-26
[3]   Photocatalytic reduction of CO2 with H2O on titanium oxides anchored within micropores of zeolites: Effects of the structure of the active sites and the addition of Pt [J].
Anpo, M ;
Yamashita, H ;
Ichihashi, Y ;
Fujii, Y ;
Honda, M .
JOURNAL OF PHYSICAL CHEMISTRY B, 1997, 101 (14) :2632-2636
[4]   In situ ATR-FTIR study of H2O and D2O adsorption on TiO2 under UV irradiation [J].
Belhadj, Hamza ;
Hakki, Amer ;
Robertson, Peter K. J. ;
Bahnemann, Detlef W. .
PHYSICAL CHEMISTRY CHEMICAL PHYSICS, 2015, 17 (35) :22940-22946
[5]  
CAI RX, 1992, CANCER RES, V52, P2346
[6]   Evidence for O2- radical stabilization at surface oxygen vacancies on polycrystalline TiO2 [J].
Carter, Emma ;
Carley, Albert F. ;
Murphy, Damien M. .
JOURNAL OF PHYSICAL CHEMISTRY C, 2007, 111 (28) :10630-10638
[7]  
Che M., 2012, CHARACTERIZATION SOL
[8]   Bulk and Surface Polarons in Photoexcited Anatase TiO2 [J].
Di Valentin, Cristiana ;
Selloni, Annabella .
JOURNAL OF PHYSICAL CHEMISTRY LETTERS, 2011, 2 (17) :2223-2228
[9]   Dynamics of Interfacial Charge Transfer to Formic Acid, Formaldehyde, and Methanol on the Surface of TiO2 Nanoparticles and Its Role in Methane Production [J].
Dimitrijevic, Nada M. ;
Shkrob, Ilya A. ;
Gosztola, David J. ;
Rajh, Tijana .
JOURNAL OF PHYSICAL CHEMISTRY C, 2012, 116 (01) :878-885
[10]   Role of Water and Carbonates in Photocatalytic Transformation of CO2 to CH4 on Titania [J].
Dimitrijevic, Nada M. ;
Vijayan, Baiju K. ;
Poluektov, Oleg G. ;
Rajh, Tijana ;
Gray, Kimberly A. ;
He, Haiying ;
Zapol, Peter .
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 2011, 133 (11) :3964-3971