463-57-0Relevant articles and documents
Highly conductive PEDOT:PSS films prepared through a treatment with geminal diols or amphiphilic fluoro compounds
Xia, Yijie,Ouyang, Jianyong
, p. 1785 - 1792,8 (2012)
Poly(3,4-ethylene dioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) films with high conductivity can have important application as the transparent electrode of optoelectronic devices. In this paper, we report the significant conductivity enhancement of PEDOT:PSS through a treatment with germinal diols which have two hydroxyl groups connected to one carbon atom or amphiphilic fluoro compounds which have hydrophobic fluorocarbon groups and hydrophilic hydroxyl or carboxylic groups. Several compounds, including hexafluoroacetone, cyclohexanehexone, formaldehyde, acetaldehyde, and perfluorobenzophenone, which could convert into geminal diols, were used to treat PEDOT:PSS films. The conductivity enhancements are generally consistent with the equilibrium constants for the conversion of these compounds into geminal diols. PEDOT:PSS films were also treated with several amphiphilic fluoro compounds. The conductivity was significantly enhanced when PEDOT:PSS films were treated with hexafluoroisopropanol, trifluoroacetic acid and heptafluorobutyric acid, while it hardly changed when they were treated with 2,2,2-trifluoroethanol. Conductivities of more than 1000 S cm-1 were observed on the treated PEDOT:PSS films. The mechanism for the conductivity enhancement of PEDOT:PSS through the treatment with geminal diols or amphiphilic fluoro compounds is attributed to the phase segregation of PSSH from PEDOT:PSS and conformational change of the PEDOT chains as the results of the compounds-induced reduction in the Coulombic attraction between the positively charged PEDOT and negatively charged PSS chains.
Kinetics and Mechanism of the Photooxidation of Formaldehyde. 1. Flash Photolysis Study
Veyret, Bernard,Lesclaux, Robert,Rayez, Marie-Therese,Rayez, Jean-Claude
, p. 2368 - 2374 (1989)
Transient species in the photooxidation of formaldehyde in air have been investigated by using the technique of flash photolysis kinetic spectroscopy.The absorption spectrum attributed to the HOCH2O2 radical was observed with a maximum near 230 nm.This radical is formed by the reaction HO2+HCHOHOCH2O2 (1,-1).The rate constants were measured for the two reactions: k1=7.7E-15*exp cm3 molecule-1 s-1 and k-1=2.0E12*exp s-1.The equilibrium constant is K1*=3.85E-27*exp(7625/T) cm3 molecule-1, which corresponds to a reaction enthalphy ΔH10=-16.25+/-0.30 kcal mol-1,which is based on the Kp value and quantum calculations of ΔS00 and therefore determined accurately.Kinetic measurements performed under various experimental conditions allowed determinations of the rate constants for the reactions HO2+HOCH2O2products (3) and 2HOCH2O2>O2+CH2(OH)2+HCOOH (4b); k3=5.6E-15*exp; k4b=5.65E-14*exp cm3 molecule-1 s-1.The branching ratios for k3 and k4 were determined in separate experiments described in part 2 of this work.
Kinetics and Mechanism of the Photooxidation of Formaldehyde. 2. Molecular Modulation Studies.
Burrows, J. P.,Moortgat, G. K.,Tyndall, G. S.,Cox, R. A.,Jenkin, M. E.,et al.
, p. 2375 - 2382 (1989)
Transient species in the photooxidation of formaldehyde in air have been investigated by using the technique of modulated photolysis-long path kinetic spectroscopy.A transient absorption spectrum consisting of a broad band with a maximum near 230 nm was obseved, which is attributed to the HOCH2O2 radical formed by the reaction HO2+HCHOHOCH2O2 (1).The equilibrium constant, K1* was estimated from these measurements of the HOCH2O2 radical together with measurements of HO2 obtained with diode laser infrared absorption spectroscopy:K1*=4.0(+4.0,-2.0)E-16 cm3 molecule-1 at 298 K.Kinetic measurement of the two radicals allowed determination of the rate coefficients at 298 K for the following reactions: HOCH2+HO2products (3), k3=(1.2+/-0.3)E-11 cm3 molecule-1 s-1; 2HOCH2O2HCOOH+CH2(OH)2+O2 (4b), k4b=(5.6+/-2.8)E-13 cm3 molecule-1 s-1.The alternative pathway, 2HOCH2O22HOCH2O+O2 (4a), followed by HOCH2O+O2 leads to the chain generation of formic acid.The rate coefficient for reaction 4a, k4a=(5.5+/-1.1)E-12 cm3 molecule-1 s-1, was determined from the yields of formic acid.
AEROBIC ELECTROCATALYTIC OXIDATION OF HYDROCARBONS
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Paragraph 0074, (2022/01/04)
This invention is directed to a method of oxygenating hydrocarbons with molecular oxygen, O2, as oxidant under electrochemical reducing conditions, using polyoxometalate compounds containing copper such as Q10 [Gu4(H2O)2(B-α-PW9O)2] or Q12{ [Cu(H2O)]3[(A-α- PW9O34)2(NO3)-] } or solvates thereof as catalysts, wherein Q are each independently selected from alkali metal cations, alkaline earth metal cations, transition metal cations, NH4+,H+ or any combination thereof.
Highly Active Subnanometer Au Particles Supported on TiO2 for Photocatalytic Hydrogen Evolution from a Well-Defined Organogold Precursor, [Au5(mesityl)5]
Siddiqi, Georges,Mougel, Victor,Copéret, Christophe
supporting information, p. 4026 - 4033 (2016/05/19)
A highly efficient H2 evolution photocatalyst based on TiO2 supported subnanometer Au particles was developed on the basis of the reaction of a gold(I) molecular precursor [Au5Mes5] (Mes = 2,4,6-trimethylphenyl), with titanium dioxide partially dehydroxylated at 120 °C. IR, UV-vis, elemental analysis, XANES, and STEM-EDX show that the deposition of [Au5Mes5] onto TiO2 leads to the formation of both subnanometer Au particles and chemisorbed [Au5Mes5]. The remaining organic ligands are removed via a mild treatment under H2, yielding subnanometer gold(0) particles. A range of Au loadings (0.3, 0.9, 2.4 wt %) with similar particle sizes (2 are obtained and tested in methanol-assisted photocatalytic hydrogen production under UV light. These catalysts display significantly higher activity than a commercial reference Au-TiO2 catalyst. The presence of chemisorbed [Au5Mes5] in the as-synthesized catalyst further improved activity, albeit at the expense of stability. This work demonstrates a simple synthetic route to obtain subnanometer Au particles on TiO2 that display exceptional activity in photocatalysis.
Photoinduced Homolysis of Alkyl-Cobalt(III) Bonds in a Cyclodextrin Cage
Imabeppu, Kohei,Kuwano, Hiroyuki,Yutani, Eriko,Kitagishi, Hiroaki,Kano, Koji
, p. 1784 - 1789 (2016/05/02)
Photodecomposition of methyl- and ethyl-CoIII complexes of meso-tetrakis(4-sulfonatophenyl)porphyrin (CH3- and C2H5-CoIIITPPSs) was used as a reaction probe to study the cage effect of cyclodextrin capsules formed by two per-O-methylated β-cyclodextrin (TMe-β-CD) molecules and their covalently linked dimer, Ph2CD. The photodecomposition of CH3-CoIIITPPS under aerobic conditions was markedly suppressed in the presence of TMe-β-CD and Ph2CD, while C2H5-CoIIITPPS was less affected. Alkyl-CoIIITPPS formed two types of inclusion complex with Ph2CD, the alkyl groups in Type 1 being located at the opposite side of the phenyl linker of Ph2CD and those in Type 2 being located at the same side. The photodecomposition of C2H5-CoIIITPPS in Type 1 proceeded via an ethylperoxo complex, while that in Type 2 occurred via a radical pair generated in a narrow, rigid cage to form ethylene and CoIITPPS.