Visible light-induced photocatalysis through surface plasmon excitation of platinum-metallized titania for photocatalytic bleaching of rhodamine B

Abstract

Nanocomposites consisting of titania nanoparticles and metallic platinum were prepared via a soft chemical reduction method. The detailed structural, compositional, and optical characterization and physicochemical properties of the obtained products were analyzed by X-ray diffraction, nitrogen adsorption, Raman spectroscopy, UV-Vis diffuse reflectance spectroscopy, photoluminescence spectroscopy, and FT-IR spectroscopy techniques. Employing photodegradation of rhodamine B as the model reaction, we found that the as-prepared Pt/TiO 2 nanocomposite showed an excellent photocatalytic oxidation activity under visible light irradiation. On the basis of these results, the intrinsic mechanism of visible light-induced photocatalytic oxidation of organic compounds on the platinized titania is proposed and discussed. The superior visible lightdriven photocatalytic efficiency of the Pt/TiO 2 nanocomposite photocatalyst can be ascribed to the high efficiency of charge-pair separation due to the presence of deposited Pt serving as electron sinks to retard the rapid e --h ? couple recombination; the good photoabsorption capacity in the visible light region; and the higher concentration of surface hydroxyl groups, which are able to effectively scavenge photogenerated valence band holes. Accumulation of the holes at the catalyst surface increases the probability of the formation of OHÁ as a reactive species that readily oxidizes the organic dye molecule.

Graphene-wrapped Ag 3 PO 4 /LaCO 3 OH heterostructures for water purification under visible light

“…Azo compounds account for 65%-75% of these dye pollutants, and it is estimated that about 12% of the dye utilized in these industries is lost annually during the textile manufacturing and processing operations [3]. The direct discharge of these colored dyes into the environment without treatment creates severe environmental pollution problems as toxic and potentially carcinogenic substances are A C C E P T E D M A N U S C R I P T 3 released into the aquatic media [1][2][3]. Hence, the disposal of wastewater is a worldwide environmental concern and its treatment is of the utmost importance.…”

“…Pesticides, dyes, and a variety of chemicals released from the textile, agricultural, and pharmaceutical industries are the main water contaminants [2]. The textile industry uses numerous dyes and is thus the largest source of colored dye effluents.…”

Measurement of intrinsic catalytic activity of Pt monometallic and Pt-MoOx interfacial sites over visible light enhanced PtMoOx/SiO2 catalyst in reverse water gas shift reaction

“…[33,34] Visible light absorption of the Pt nanoparticles (~5 nm diameter) has been reported to enhance catalytic activity in oxidation reactions, ascribed to interband excitation of Pt atoms. [35][36][37][38] Visible light illumination of Pt enhanced the activity of rhodamine B degradation with Pt/TiO 2 , [39] organic pollutant decomposition over Pt/Bi 2 O 3 , [40] and oxidation reactions over Pt/TiO 2 . [41] According to these studies, the visible light enhancement of Pt nanoparticles was due to LSPR.…”

Synthesis of TiO2 and SiO2 Oxide Systems, Containing Nanoparticles of Palladium and Platinum

“…Materials based on titanium dioxide are well known for the pronounced catalytic and photocatalytic properties [1][2][3][4][5][6][7] . Presence of metallic nanoparticles formed of platinum group metals in oxide systems based on titanium dioxide, often leads to increased catalytic activity [8][9][10][11][12] .…”

“…As precursor of titanium dioxide titanium alkoxide or complexes of titanium tetrachloride with for mic acid amides were used, e. 6 ] by hydrazine or oxalate reduction. Also used tetramethoxysilane, titanium tetraisopropoxide and 1,10-decanediol.…”