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The purpose of this study is to prepare the micro/nanorod materials in low middle temperature to remove the volatile organic compound (taking toluene as target) in the waste air pollution stream using a combined reactor with photo- and thermo-reaction at the same time. The micro/nanorod molecular sieve (Octahedral manganese cryptomelanes, K-OMS-2) are fabricated and coated on support of Al2O3, and the catalyst is used in the combined reactor with light and heat sources at feasible temperature to convert the target. The decomposition/removal efficiency of toluene in photo- and thermos-reactor as well as the photoelectric characteristic analyses are evaluated. The operation parameters of temperature of reactor and initial concentrations etc. are carried out, meanwhile, the characteristic analyses (EA, TEM-EDS, XRD, LaB6-TEM, XPS, FTIR etc.) are also examined in order to find the optimum conditions. In the performance of the photodegradation reaction, the optimum n is the catalyst of K-OMS-2/Al2O3 calcination temperature of 523 K with UVLED of 633 hr-1 space velocity (SV), and the maximum value is 95.56%. However, the CO2 conversion is not obvious in the photodegradation reaction due to the not complete degradation. In the photo- and thermosdegradation reactor, the situation can be improved and the maximum n of 95.25% and CO2a conversion of 95% can reach at 873K with UVLED. The result proves that the combined reactor for photo- and thermos-degradation can work in both industrial or domestic application in air pollution control. [ABSTRACT FROM AUTHOR]

The photocatalytic activity of copper oxide (CuO) and C, N, and S-tri-doped TiO2 photocatalysts (Cu/TiNxSyO2-x-yCz, Cu/TNST) and their applications on photodegradation of volatile organic compounds were investigated, taking toluene as a model compound and irradiation of different light sources (visible light lamp (VLL), white light-emitting-diode, and red-light emitting-diode). The metal and non-metal co-doped catalysts were synthesized and the comparisons with different loading percentages (2, 5, 10, and 12%) of copper on TNST were tested. From the analysis of the photoelectrochemical characteristics, the maximum power (Pmax) was 1.38 pW at 5 Cu/TNST solar cell (Cu/TNSSC) with VLL. Furthermore, the maximum degradation efficiency (q) of toluene appeared also at 5 Cu/TNST as well as at VLL light irradiation. The pseudo-first-order rate constant (kobs) of 2, 5, 10, and 12 Cu/TNST were 0.0172, 0.0726, 0.0264, and 0.0076 min-1, respectively. Langmuir-Hinshelwood model (L-H model) was then evaluated and simulated for the different initial concentrations with the highest efficiency catalyst of 5Cu/TNST. The reaction rate constant (k) and adsorption equilibrium constant (KL) of 5Cu/TNST under VLL irradiation were 0.7307 and 0.0474 ppmv-1, respectively. The addressed kinetic models could simulate the system behavior appropriately and the L-H model obtained in this study can be used in the design of photocatalytic reactors for air pollution control and energy production. [ABSTRACT FROM AUTHOR]

This study investigated the surface modification of N- and S- doped TiO2 (TiNxSyO2-x-y) and photoelectrochemical characteristics of dyesensitized TiNxSyO2-x-y using visible light sources for further application of photocatalysis. TiNxSy O2-x-y was prepared by Ti(SO4)2 and NH3 calcined at 400 °C (723 K). TiO2 and TiNxSyO2-x-y films on indiumdoping tin oxide (ITO) promoted with nature Eosin Y (C20H6Br4Na2O5) sensitizers, which were prepared by precipitation method following by calcined at muffle furnace and tested for electricity and photoelectrochemical characteristics. The opencircuited output voltage (Voc), short-circuit output current (Isc) and maximum power (Pm) of TiO2 solar cell (TSC) and TiNxO2-xSy solar cell (TNSSC) dyed with Eosin Y (ETSC and ETNSSC) under the irradiation of VLL, BLED, WLED and RLED were measured. The Voc per gram (Voc/g) of ETNSSC was in the order of BLED (26.7) > WLED (26.1) > RLED (25.8) > VLL (22.0). The maximum value of Isc and Pm were 0.023 mA and 2.51 μW for ETNSSC under BLED, respectively. All the values of Voc, Isc and Pm of ETNSSC are larger than those of TSC and ETSC. This result shows that the TiNxO2-xSy solar cell dyed with Eosin Y can largely increase the photoelectrochemical characteristics and change the absorption light wavelength to red shift obviously. It is expected to have more applications in the photocatalytic degradation of pollutants. [ABSTRACT FROM AUTHOR]