Squaraine dye sensitized TiO2 nanocomposites with enhanced visible-light photocatalytic activity

Li, Zhongyu; Fang, Yongling; Xu, Song

doi:10.1016/j.matlet.2012.11.135

Cited by 20 publications

(7 citation statements)

References 12 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…14 However, there are a number of drawbacks of pure TiO 2 in photocatalysis, including the relatively large band-gap and the related fact that it can only absorb a small portion of UV radiation. 15 To facilitate the usage of energy from natural sunlight, certain routes have been attempted to modify TiO 2 accordingly, including non-/ transition-metal ion doping, 16,17 sensitization, 18 ion implantation, 19 narrower band-gap semiconductor coupling, 20 and p-conjugated structure compositing, 21 etc. For example, Rey et al 16 synthesized TiO 2 -WO 3 photocatalysts, which exhibited higher catalytic activity than that of pure TiO 2 for the removal of a mixture of emerging contaminants through photocatalytic ozonation under visible light radiation.…”

Section: Introductionmentioning

confidence: 99%

Recent developments in heterogeneous photocatalytic water treatment using visible light-responsive photocatalysts: a review

et al. 2015

View full text Add to dashboard Cite

show abstract

Section: Introductionmentioning

confidence: 99%

Recent developments in heterogeneous photocatalytic water treatment using visible light-responsive photocatalysts: a review

et al. 2015

View full text Add to dashboard Cite

show abstract

“…Photocatalytic activity of Coupled TiO 2 6.1 Photocatalytic activity of TiO 2 with organic compounds Photodegradable polyvinyl chloride (PVC)-vitamin C(VC)-TiO 2 nanocomposite film show high photocatalytic activity which can be explained on the basis of the formation of a Ti IV -VC charge-transfer complex with five-member chelate ring structure and followed by rapid photogenerated charge separation [145]. Enhanced photocatalytic activity of the novel 1,3-bis(N-3H-3,3-dimethyl-2-methylene indolenine) squaraine dye (ISQ) sensitized TiO 2 nanocomposites was reported by Li et al, [146] for the degradation of MB under the visible-light irradiation. These particles showed superior photocatalytic stability after 5 successive cycles under visible-light.…”

Section: Photocatalytic Activity Of Non Metal Doped Tio 2 Nmsmentioning

confidence: 92%

PHOTOCATALYTIC ACTIVITY OF TiO2 NANOMATERIAL

Jain

Vaya

2017

J. Chil. Chem. Soc.

View full text Add to dashboard Cite

Nanomaterials synthesize by different techniques exhibit excellent photocatalytic activity. These catalysts could be employed for environmental remediation, renewable energy sources, photocatalysis and many other applications in various fields. Nanophotocatalyst has been used for the treatment of hazardous materials such as industrial effluents containing complex organic compounds, dyes and metal ions successfully. The multidimensional study of composition, shape, size, surface area and nanostructure and different operating parameters like pH, concentration, temperature etc, of these photocatalyst help in current and further development of photocatalysts for different applications . The photocatalytic activity of nanoparticles has made a great contribution in providing definitive mechanistic information about the photocatalytic processes.The main aim of this review paper is to give an overview of the enhanced photocatalytic activities of titanium dioxide (TiO 2 ) nanoparticles. This review includes the basic properties of photocatalyst and mechanim of photocatalysis process followed by unique photocatalytic properties and research of TiO 2 nanoparticles as photocatalysts. An effort has also been made to give an overview of expedient photocatalytic activity of these doped nanoparticles. Many investigators have reported the enhanced photocatalytic activity by the degradation of dyes as a model compound.Key Words: photocatalysts, TiO 2 , nanoparticles, AOPs. INTRODUCTIONToday, the industrial revolution is putting its negative impacts on the entire globe. Over the year's complexities, varieties and the amount of hazardous compounds are increasing in wastewater discharged by various printing, dyeing, textile and other chemical industries into the ecosystem. These compounds are highly carcinogenic and mutagenic. Apart from aesthetic pollution, they are causing eutrophication, high Chemical Oxygen Demand (COD) and Biological Oxygen Demand (BOD). In addition to that, these compounds absorb sunlight strongly which affects the photosynthetic activity of aquatic plants and seriously threatening the whole ecosystem [1,2]. Now days the perilous effects of organic dyes to the environment is a particular concern. To resolve this problem, the photocatalytic decomposition processes are being employed by many researchers to degrade the organic pollutants of industrial wastewater before discharge into receiving media [3]. Although various chemical and physical process are available for the degradation of textile effluents but they generate non-biodegradable contaminations and further require treatment involving expensive procedure. Conventional techniques such as coagulation/ flocculation, membrane separation, absorption methods as well as biological methods are also inefficient for removal of complex organic compounds [4][5][6][7][8][9][10][11]. To resolve such types of problems Advanced Oxidation Processes (AOPs) are proven to be most promising technique which is based on the generation of highly reactive hydroxyl radica...

show abstract

“…TiO 2 nanoparticles were fabricated by an improved polymerization-induced colloid aggregation (Im-PICA) method as described in ref . Simultaneously, the synthesis of the three SQs was slightly modified from that reported in ref .…”

Section: Experimental Methodsmentioning

confidence: 99%

Effect of Dye Structure on Optical Properties and Photocatalytic Behaviors of Squaraine-Sensitized TiO₂ Nanocomposites

Fang

Yang

et al. 2014

J. Phys. Chem. C

Self Cite

View full text Add to dashboard Cite

TiO 2 nanoparticles obtained by an improved polymerization-induced colloid aggregation (Im-PICA) method were sensitized by three squaraine dyes to construct dye/TiO 2 nanocomposite photocatalysts (1:3 mass ratios) with visible-light responses by a facile hydrothermal method. Scanning electron microscopy (SEM) and transmission electron miscroscopy (TEM) were employed to visually observe the surface morphologies of the samples. We studied the visible-light response using UV−vis diffuse reflectance spectroscopy and optical band gap calculations using the Tauc plot equation. The dyes exhibit excellent thermal stability, which is ascribed to the decomposition temperature reaching 300 °C based on thermogravimetric−differential thermogravimetric (TG−DTG) analysis. The photocatalytic activities of the as-prepared SQ/TiO 2 composites were assessed in terms of the degradation rate of methylene blue (MB) under visible-light irradiation. The ISQ/TiO 2 composites achieved best enhancement of photocatalytic activity under 150 min of visible-light irradiation. When ISQ/TiO 2 nanocomposites were applied for different photocatalytic degradation cycling times, the degradation rate still reached 68%, which reflects the fact that SQ/TiO 2 composites have a high photostability in the photocatalytic process. When taking the degradation rate and photoresponse into consideration, the combination mode between the ISQ dye and TiO 2 that obtained the optimal degradation rate tended to be a hydrogen bond, which exhibited a stronger binding force than the simple physical absorption of m-ISQ/TiO 2 and c-BSQ/TiO 2 based on the FT-IR analysis. Using total organic carbon (TOC) test and liquid chromatography (LC) results, we verified the degree of mineralization of the MB molecule. Based on the fluorescence spectra, the highest fluorescence quantum yield of ISQ dye (0.124) was far greater than those of c-BSQ (0.036) and m-ISQ (0.02). The molecular structures of the squaraine dyes and the electron distributions of their highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) states were given by geometrical optimization with Gaussian 98 at the B3LYP/6-311+G(d,p) level. Compared with the optical band gap calculated using the Tauc plot equation, we suggest that its energy was slightly less than the band gap due to the absorbed photon. This might be related to the localized central electronic, phonon, and local energy levels between the conduction band (CB) and the valence band (VB). The value of the optical band gap calculated from UV diffuse reflection spectroscopy (DRS) becomes less than the theoretical calculated energy band gap.

show abstract

Squaraine dye sensitized TiO2 nanocomposites with enhanced visible-light photocatalytic activity

Cited by 20 publications

References 12 publications

Recent developments in heterogeneous photocatalytic water treatment using visible light-responsive photocatalysts: a review

Recent developments in heterogeneous photocatalytic water treatment using visible light-responsive photocatalysts: a review

PHOTOCATALYTIC ACTIVITY OF TiO2 NANOMATERIAL

Effect of Dye Structure on Optical Properties and Photocatalytic Behaviors of Squaraine-Sensitized TiO₂ Nanocomposites

Contact Info

Product

Resources

About

Squaraine dye sensitized TiO2 nanocomposites with enhanced visible-light photocatalytic activity

Cited by 20 publications

References 12 publications

Recent developments in heterogeneous photocatalytic water treatment using visible light-responsive photocatalysts: a review

Recent developments in heterogeneous photocatalytic water treatment using visible light-responsive photocatalysts: a review

PHOTOCATALYTIC ACTIVITY OF TiO2 NANOMATERIAL

Effect of Dye Structure on Optical Properties and Photocatalytic Behaviors of Squaraine-Sensitized TiO2 Nanocomposites

Contact Info

Product

Resources

About

Effect of Dye Structure on Optical Properties and Photocatalytic Behaviors of Squaraine-Sensitized TiO₂ Nanocomposites