- Efficient electron injection due to a special adsorbing group's combination of carboxyl and hydroxyl: Dye-sensitized solar cells based on new hemicyanine dyes
-
A series of new benzothiazolium hemicyanine dyes (HC-1, HC-2, HC-3, HC-4, and HC-5 in Scheme 1) were designed and synthesized for sensitization of nanocrystalline TiO2 electrodes by introducing carboxyl, hydroxyl, or sulfonate anchoring groups onto the dyes' skeletons. A naphthothiazolium hemicyanine with both sulfonate and hydroxyl (HC-6) was also prepared for comparison. The photophysical and photoelectrochemical studies revealed that three kinds of efficiencies, i.e. the fluorescence quenching efficiencies of the dyes by colloidal TiO2, the monochromatic incident photon-to-current conversion efficiencies (IPCEs) for the dye-sensitized TiO2 electrodes, and the overall photoelectric conversion efficiencies (η) for the dye-sensitized solar cells (DSSCs) based on these hemicyanines, all depended strongly on the anchoring group types and decreased in the order: carboxyl + hydroxyl > carboxyl > sulfonate + hydroxyl, indicating the importance of the dyes' adsorbing groups for their sensitization effects in DSSCs. The combination of carboxyl and hydroxyl as anchoring groups led to highly efficient IPCEs over a wide spectrum region with the maximum IPCE of 73.6% and a η of 5.2% under AM1.5 Global simulated light (80 mW cm-2) for the HC-1 based DSSC, which may result from the complex formation between HC-1 and TiO2 and the cathodic shift of the excited state oxidation potential. The Royal Society of Chemistry 2005.
- Chen, You-Sheng,Li, Chao,Zeng, Zhang-Hua,Wang, Wei-Bo,Wang, Xue-Song,Zhang, Bao-Wen
-
-
Read Online
- Optical mercury sensing using a benzothiazolium hemicyanine dye
-
The selectivity and sensitivity of a benzothiazolium hemicyanine dye toward mercury(II) in aqueous solutions are described. Mercury Ions coordinate to the dye forming a 1:1 complex. This interaction induces a color change in the dye at micromolar concentrations of mercury. Furthermore, the color change and quenching of the dye emission are selective for mercury when compared with other ions such as lead(II), cadmium(II), zinc(II), or iron(II).
- Tatay, Sergio,Gavina, Pablo,Coronado, Eugenio,Palomares, Emilio
-
-
Read Online
- Selective probes targeting c-MYC Pu22 G-quadruplex and their application in live mice imaging
-
Several probes containing benzothiazole-guided conjugated systems (BGCS) were designed and synthesized, and two molecules (BGCS5 and BGCS6) of which were discovered as selective probes targeting c-MYC Pu22 G-quadruplex DNA. The fluorescence intensity of BGCS5 and BGCS6 in the presence of c-MYC Pu22 far exceeds that of the typical G4 probe TO1. Especially, the fluorescence of BGCS6 increased almost 193-fold in the presence of c-MYC Pu22 G4 compared to that alone in aqueous buffer condition with almost no fluorescence and 10–30 folds than those in the presence of other DNAs, which will be useful tools for disease detection in mammals.
- Huang, Wenbo,Ke, Shaoyong,Shi, Liqiao,Xu, Shengzhen,Yu, Zhuo
-
supporting information
(2021/10/29)
-
- Synthesis of novel colorants for DSSC to study effect of alkyl chain length alteration of auxiliary donor on light to current conversion efficiency
-
Five (MA1-MA5) hemicyanine based sensitizer having N, N-diethyl aniline as a primary donor and hydroxy or alkoxy as an auxiliary donor have been synthesized to establish a correlation between amphiphilic nature of the sensitizer and charge recombination. A strong electron withdrawing 3-(carboxymethyl)-2-methylbenzo[d]thiazol-3-ium bromide has been explored as an acceptor. All the dyes were characterized by 1H-NMR, 13C-NMR and CHN analysis. The photophysical properties of these dyes were recorded in seven different solvents which do not show any significant impact on absorption and emission maxima while molar absorptivity coefficient decreases with increase in alkyl chain length. These dyes show very poor emission in all the solvents. Nano-crystalline mesoporous TiO2 based dye-sensitized solar cells were fabricated using MA1 to MA5 sensitizers to evaluate their photovoltaic performance. MA5 having six carbon alkyl chain shows maximum efficiency of 4.97% while MA1 without any alkyl chain shows the lowest efficiency of 3.40%. As the length of alkyl chain increase efficiency increase due to increment in short circuit current (Jsc) and retardation in the recombination process. Density functional theory (DFT) and time-dependent density functional theory (TD-DFT) were explored to obtain vertical excitation, HOMO-LUMO energy and electron density distribution.
- Jadhav, Manoj M.,Vaghasiya, Jayraj V.,Patil, Dinesh,Soni, Saurabh S.,Sekar, Nagaiyan
-
p. 119 - 129
(2019/04/05)
-
- A new ratiometric and colorimetric chemosensor for cyanide anion based on Coumarin-hemicyanine hybrid
-
A hybrid coumarin-hemicyanine dye, Cou-BT, was developed as a new ratiometric and colorimetric sensor for cyanide with a sensing mechanism via nucleophilic addition of cyanide anion to the benzothiolium group. Cou-BT shows high sensitivity and selectivity for cyanide detection over other common anion species in aqueous acetonitrile solution. The calculated pseudo-first-order rate constant for cyanide anion addition was (2.13 ± 0.08) × 10 -2 s-1 at 298 K, and the detection limit was estimated to be 0.64 μM. The DFT and TDDFT calculation results suggest that the ratiometric and colorimetric sensing behavior of Cou-BT upon its reaction with cyanide was due to the interrupted π-conjugation and blocked ICT progress.
- Yang, Zhenghao,Liu, Zhipeng,Chen, Yuncong,Wang, Xiaoqing,He, Weijiang,Lu, Yi
-
supporting information; scheme or table
p. 5073 - 5076
(2012/08/08)
-
- Westphal Reaction in Solid-Phase
-
(Equation presented) A library of cycloimonium salts has been prepared through Westphal reaction in solid-phase. By reaction of solid-support-bound azolium or azinium acetates 2, 1,2-diketones 4, and base, cycloimonium salts 5 were synthesized in good to high yield and purities.
- Delgado, Francisca,Linares, M. Lourdes,Alajarin, Ramon,Vaquero, Juan J.,Alvarez-Builla, Julio
-
p. 4057 - 4060
(2007/10/03)
-