Highly Selective Deethylation of Rhodamine B on Prepared in Supercritical Fluids

Pure phase anatase TiO2 nanoparticles with sizes of 5–8 nm and varying crystallinity were synthesized in supercritical isopropanol/water using a continuous flow reactor. Their photodegradation of rhodamine B (RhB) was evaluated under visible light irradiation. The as-prepared TiO2 nanoparticles show much higher photodegradation efficiencies than commercial Degussa P25 TiO2. Moreover, the photodegradation of RhB on the as-prepared TiO2 follows a different process from that on P25 TiO2, quicker N-deethylation and slower cleavage of conjugated chromophore structure. Based on PXRD, TEM, and BET measurements, these two photodegradation properties have been explained by the physicochemical properties of TiO2.

[1]  M. Jaroniec,et al.  Tunable photocatalytic selectivity of TiO2 films consisted of flower-like microspheres with exposed {001} facets. , 2011, Chemical communications.

[2]  Dong Hyun Kim,et al.  Photocatalytic Properties of Nanotubular-Shaped Powders with Anatase Phase Obtained from Titanate Nanotube Powder through Various Thermal Treatments , 2011 .

[3]  J. Hamilton,et al.  Photocatalytic Enhancement for Solar Disinfection of Water: A Review , 2011 .

[4]  W. Oh,et al.  The Improved Photocatalytic Properties of Methylene Blue for V2O3/CNT/TiO2 Composite under Visible Light , 2010 .

[5]  Chuncheng Chen,et al.  Semiconductor-mediated photodegradation of pollutants under visible-light irradiation. , 2010, Chemical Society reviews.

[6]  Zisheng Zhang,et al.  Applications of Photocatalytic Disinfection , 2010 .

[7]  Mietek Jaroniec,et al.  Tunable photocatalytic selectivity of hollow TiO2 microspheres composed of anatase polyhedra with exposed {001} facets. , 2010, Journal of the American Chemical Society.

[8]  B. Iversen,et al.  Continuous flow supercritical water synthesis and crystallographic characterization of anisotropic boehmite nanoparticles , 2010 .

[9]  Cheng Sun,et al.  Visible light-driven photocatalytic degradation of rhodamine B over NaBiO3: pathways and mechanism. , 2009, The journal of physical chemistry. A.

[10]  R. Naidu,et al.  Tailored titanium dioxide photocatalysts for the degradation of organic dyes in wastewater treatment: A review , 2009 .

[11]  B. Iversen,et al.  Comparison of T-piece and concentric mixing systems for continuous flow synthesis of anatase nanoparticles in supercritical isopropanol/water , 2009 .

[12]  A. Fujishima,et al.  TiO2 photocatalysis and related surface phenomena , 2008 .

[13]  Zheshen Li,et al.  Surface properties and photocatalytic activity of nanocrystalline titania films , 2008 .

[14]  Chuncheng Chen,et al.  Change of adsorption modes of dyes on fluorinated TiO2 and its effect on photocatalytic degradation of dyes under visible irradiation. , 2008, Langmuir : the ACS journal of surfaces and colloids.

[15]  J. S. Pedersen,et al.  Critical size of crystalline ZrO(2) nanoparticles synthesized in near- and supercritical water and supercritical isopropyl alcohol. , 2008, ACS nano.

[16]  Can Li,et al.  Importance of the relationship between surface phases and photocatalytic activity of TiO2. , 2008, Angewandte Chemie.

[17]  R. Ocampo-Pérez,et al.  Adsorption of Fluoride from Water Solution on Bone Char , 2007 .

[18]  Z. Zou,et al.  Low Temperature Synthesis and Photocatalytic Activity of Rutile TiO2 Nanorod Superstructures , 2007 .

[19]  J. S. Pedersen,et al.  Supercritical Propanol–Water Synthesis and Comprehensive Size Characterisation of Highly Crystalline anatase TiO2 Nanoparticles , 2006 .

[20]  E. Søgaard,et al.  Low Temperature Synthesis of Metal Oxides by a Supercritical Seed Enhanced Crystallization (SSEC) Process , 2006 .

[21]  Hyunwoong Park,et al.  Photocatalytic reactivities of Nafion-coated TiO2 for the degradation of charged organic compounds under UV or visible light. , 2005, The journal of physical chemistry. B.

[22]  J. Raulin,et al.  Heterogeneous photocatalysis: state of the art and present applications In honor of Pr. R.L. Burwell Jr. (1912–2003), Former Head of Ipatieff Laboratories, Northwestern University, Evanston (Ill). , 2005 .

[23]  J. S. Pedersen,et al.  Characterization of nanosized partly crystalline photocatalysts , 2004 .

[24]  H. Jang,et al.  Effect of Particle Size and Phase Composition of Titanium Dioxide Nanoparticles on the Photocatalytic Properties , 2001 .

[25]  P. F. Greenfield,et al.  Role of the Crystallite Phase of TiO2 in Heterogeneous Photocatalysis for Phenol Oxidation in Water , 2000 .

[26]  Jincai Zhao,et al.  Photoassisted Degradation of Dye Pollutants. 3. Degradation of the Cationic Dye Rhodamine B in Aqueous Anionic Surfactant/TiO2 Dispersions under Visible Light Irradiation: Evidence for the Need of Substrate Adsorption on TiO2 Particles , 1998 .

[27]  Jincai Zhao,et al.  Photoassisted Degradation of Dye Pollutants. V. Self-Photosensitized Oxidative Transformation of Rhodamine B under Visible Light Irradiation in Aqueous TiO2 Dispersions , 1998 .

[28]  M. Grätzel,et al.  A low-cost, high-efficiency solar cell based on dye-sensitized colloidal TiO2 films , 1991, Nature.

[29]  K. Honda,et al.  Photocatalysis through excitation of adsorbates. 2. A comparative study of Rhodamine B and methylene blue on cadmium sulfide , 1978 .

[30]  K. Honda,et al.  Photocatalysis through excitation of adsorbates. 1. Highly efficient N-deethylation of rhodamine B adsorbed to cadmium sulfide , 1977 .

[31]  J. Herrmann,et al.  HETEROGENEOUS PHOTOATALYSIS: STATE OF THE ART AND PRESENT APPLICATIONS , 2005 .

[32]  Jincai Zhao,et al.  Highly selective deethylation of rhodamine B: Adsorption and photooxidation pathways of the dye on the TiO2/SiO2 composite photocatalyst , 2003 .

[33]  S. Martin,et al.  Environmental Applications of Semiconductor Photocatalysis , 1995 .