Photocatalytic Improvement under Visible Light in TiO₂ Nanoparticles by Carbon Nanotube Incorporation

Abstract

Photocatalytic activity of TiO 2 nanoparticles was successfully enhanced by addition of multiwall carbon nanotubes (MWCNT) to make CNT/TiO 2 nanocomposites by sol-gel method at ambient temperature. CNT treated by HNO 3 : H 2 SO 4 treatment (1 : 3 v/v) was mixed with TiO 2 nanoparticles at various molar ratios and calcination temperatures. The optimal molar ratio of CNT : TiO 2 was found at 0.05 : 1 by weight. The optimal calcination condition was 400 ∘ C for 3 h. From the results, the photocatalytic activities of CNT/TiO 2 nanocomposites were determined by the decolorization of 1 × 10 −5 M methylene blue (MB) under visible light. CNT/TiO 2 nanocomposites could enhance the photocatalytic activity and showed faster for the degradation of MB with only 90 min. The degradation efficiency of the MB solution with CNT/TiO 2 nanocomposite achieved 70% which was higher than that with pristine TiO 2 (22%). This could be explained that CNT prevents TiO 2 from its agglomeration which could further enhance electron transfer in the composites. In addition, CNT/TiO 2 nanocomposites had high specific surface area (202 m 2 /g) which is very promising for utilization as a photocatalyst for environmental applications.

A highly sensitive printed humidity sensor based on a functionalized MWCNT/HEC composite for flexible electronics application

“…44 Further, the FT-IR spectrum of the FMWCNTs showed the peaks of carboxyl (C]O) and carbonyl (O-C]O) groups at z1650 cm À1 and z1450 cm À1 , respectively. 44,55,56 Thus, these peaks from the FT-IR indicated the presence of functional groups on the surface of FMWCNTs aer covalent acid functionalization.…”

Preparation, Characterization, and Separation Performances of Novel Surface Modified LbL Composite Membranes from Polyelectrolyte Blends and MWCNT

“…It was also observed a broad peak from OH group in the carboxylic acid group at 3,453 cm −1 . It can be confirmed that chemical modification of MWCNT was successfully carried out using acid mixture [31,[34][35][36][37][38].…”

“…A pretreatment was applied to commercial MWCNT prior to use in the preparation of composite membranes. For this purpose, MWCNT was functionalized with negatively charged carboxyl ( COOH) group as explained in the literature [7,31]. After modification of MWCNT's surface, it was expected that MWCNT can disperse very efficiently in negatively charged PAA for LbL assembly.…”

Carbon Nanotubes based Nanocomposites as Photocatalysts in Water Treatment

“…Soroodan and Fatemi synthesized TiO2/ CNTs composites using sol-gel method for the degradation of acetaldehyde. Benzyl alcohol as the linking agent was added to the TiO2/ CNTs composites resulting in homogeneously coating of TiO2 sols over the CNTs [52][53][54].…”