Synthesis and Characterization of TiO₂@C Core−Shell Composite Nanoparticles and Evaluation of Their Photocatalytic Activities

Abstract

TiO 2 @C core-shell composite nanoparticles were synthesized by a simple and efficient single-step method in a specially made Swagelok cell at different temperatures. The prepared samples were characterized by XRD, diffuse reflectance-UV-vis, Raman, TEM, HRTEM, and N 2 adsorption-desorption methods. The carbon content in the samples can be varied with reaction time and temperature. It is evident from TEM analysis that the as-prepared samples are core-shell structures of TiO 2 , anatase phase, and C. The diameter of the TiO 2 @C nanoparticles is in the range of 15-35 nm. HRTEM results showed that a few graphitic layers were wrapped on the surface of TiO 2 , and these carbon layers are responsible for suppressing other phase formations of TiO 2 even at high temperature. However, a few percentage points of the rutile phase are observed at high temperature (900 °C), evidenced from Raman analysis. The prepared samples were tested for their photochemical activities for 4-chlorophenol degradation. The sample prepared at 700 °C showed comparable activity for the degradation of 4-chlorophenol with that of Degussa P25. The photobleaching studies of methylene blue were also carried out under sunlight. It was found that the TiO 2 @C samples showed higher photocatalytic activity than Degussa P25.

Preparation and properties of antibacterial TiO2@C/Ag core–shell composite

“…Similar results were reported by Tsumura et al [28] and Shanmugam et al [17]. The amount of deposited silver depends on the initial concentration of Ag + as well as the surface area, pore structure and quantity of acidic functional groups that can act as initial active sites for adsorption [4,29].…”

“…This activity can possibly be improved using silver ions. TiO 2 @C core-shell composite has wide applications in photocatalysts [17,18] and anode materials of lithium batteries [19] owing to the excellent performance of TiO 2 and the unique structure of carbon. It also possesses some antibacterial activity and can be used as a carrier for antibacterial materials.…”

Mesoporous titania photocatalysts: preparation, characterization and reaction mechanisms

“…Also, TiO 2 @C core-shell composite nanoparticles were synthesized by a simple and efficient singlestep method in a specially made Swagelok cell at different temperatures. 143 It is evident from TEM analysis that the as-prepared samples are core-shell structures of TiO 2 , anatase phase, and C. The prepared samples were tested for their photochemical activities for 4-chlorophenol degradation. The sample prepared at 700 C showed comparable activity for the degradation of 4-chlorophenol with that of Degussa P25.…”

Size-selective photocatalytic reactions by titanium(iv) oxide coated with a hollow silica shell in aqueous solutions

“…One of the ordinal methods to provide the commercial TiO 2 selective photocatalytic functions is encapsulation of TiO 2 particles into porous substances. [23][24][25][26] However, composites obtained by this method have a propensity to decrease intrinsic photocatalytic activity of the medial TiO 2 due to the surface coverage of these substances. photocatalyst, commercially available TiO 2 particles directly incorporated into a hollow silica shell (SiO 2 /void/TiO 2 ).…”