The greyish-black precipitate was harvested selleck chemicals by centrifugation (5,000 rpm, 30 min) and was washed with ethanol several times to remove undecorated TiO2 particles, unreacted chemicals, and residual EG. Finally, the product was dried in an air oven at 60°C overnight before characterization. Characterization Morphology observation was performed using an SU-8010 field emission scanning electron microscope (FESEM; Hitachi Ltd., Tokyo, Japan) equipped with an Oxford-Horiba Inca XMax50 energy-dispersive X-ray (EDX; Oxford Instruments Analytical, High Selleck Momelotinib Wycombe, England). High-resolution transmission electron

microscopy (HRTEM) was conducted with a JEOL JEM-2100 F microscope (JEOL, Tokyo, Japan) operating at 200 kV. The X-ray powder diffraction data were obtained on a Bruker AXS (Madison, WI, USA) D8 Advance X-ray diffractometer with CuKα radiation (λ = 0.15406 nm) at a scan rate (2θ) of 0.02° s−1. The accelerating voltage and applied current were 40 kV and 40 mA, respectively. The crystallite size measurements of anatase TiO2 were quantitatively calculated using Scherrer’s equation (d = kλ/β cos θ) where d is the crystallite size, k is a constant (=0.9 assuming that the particles are spherical), β is the full width at half maximum (FWHM) intensity of the (101) peak in radians, and θ is Bragg’s diffraction ML323 chemical structure angle [26]. Raman spectra were recorded at room temperature on a Renishaw Astemizole inVia Raman

microscope (Renishaw, Gloucestershire, UK). UV-visible absorption spectra for

the samples were collected with an Agilent Cary-100 UV-visible spectroscope (Agilent Technologies, Santa Clara, CA, USA). A Nicolet iS10 Fourier transform infrared (FTIR) spectrometer (Thermo Scientific, Logan, UT, USA) was used to record the FTIR spectra of all samples. Photocatalytic CO2 reduction experiment The photocatalytic experiment for the reduction of CO2 was conducted at ambient condition in a homemade, continuous gas flow reactor. A 15-W energy-saving daylight bulb (Philips, Amsterdam, Netherlands) was used as the visible light source. The catalyst powder was first fixed into a quartz reactor. Highly pure CO2 (99.99%) was bubbled through water (sacrificial reagent) to introduce a mixture of CO2 and water vapor into the photoreactor at ambient pressure. Prior to irradiation, CO2 was purged inside the reactor for 30 min to remove the oxygen and to ensure complete adsorption of gas molecules. The light source was then turned on to initiate photocatalytic reaction. The generated gases were collected at 1-h intervals and were analyzed by a gas chromatograph (GC), equipped with a flame ionization detector (FID) (Agilent, 7890A) to determine the yield of CH4. Control experiments were also carried out in the dark, and no product gases were detected for all tested catalysts. This indicates that light irradiation was indispensable for the photoreduction of CO2 to CH4.