Dye sensitized solar cells prepared by flames stabilized on a rotating surface

A previously developed flame synthesis method was applied to the preparation of mesoporous titania films for application in dye sensitized solar cells (DSSC). The method combines the synthesis of narrowly sized, ultrafine metal oxide particles with controllable chemical and phase purity and the deposition of these particles into a uniform, porous thin film in a single step. The current work used a series of ethylene–oxygen–argon flames to produce DSSC anode films of wide ranging properties. The performance of the solar cells prepared with these anode films was studied at the fundamental level with respect to variations of the titania crystal phase purity and content resulting from changes primarily from flame stoichiometry changes. Based on the basic relationship established among flame synthesis condition-material property-cell performance, a highly efficient DSSC was designed, which shows photocurrent densities better than some of the best performing cells reported to date. Additional studies have focused on a demonstration of the suitability of the flame process in engineering TiO₂ films structurally and chemically with the potential of further improved DSSC efficiency.     

On the non-symmetric planar aligned NLC cell

The planar aligned nematic liquid crystal cell with different anchoring for the two substrates (i.e. a non-symmetric NLC cell) is investigated by an analytical method. We deduce the basic equations and the boundary conditions of the tilt angle θ of the LC director. Expressions for threshold and saturation magnetic field are obtained, and numerical results of these two quantities with variation in anchoring parameters of the two substrates are given. A symmetry breaking parameter Δ is introduced and the relations between Δ and applied field, as well as the two sets of anchoring parameters are discussed in detail. A feasible experimental plan for measurement of anchoring strengths of a series of different substrates is proposed.     

Protein Staining Agents from Cationic and Neutral Luminescent Iridium(III) Complexes

Seven luminescent iridium(III) complexes were prepared to investigate the relationships between chemical structures and properties of protein staining. For the first time, the effect of the main ligand, the π conjugation effect of the ancillary ligand, and the charge effect of organometallic complexes on protein staining has been revealed. Most importantly, this study gives the first experimental evidence of the potential applications of charge‐neutral organometallic complexes in protein staining, which could open an avenue of exploiting novel protein staining agents in the future.     

Site‐Resolved Two‐Step Relaxation Process in an Asymmetric Dy2 Single‐Molecule Magnet

Elaborate chemical design is of utmost importance in order to slow down the relaxation dynamics in single‐molecule magnets (SMMs) and hence improve their potential applications. Much interest was devoted to the study of distinct relaxation processes related to the different crystal fields of crystallographically independent lanthanide ions. However, the assignment of the relaxation processes to specific metal sites remains a challenging task. To address this challenge, a new asymmetric Dy₂ SMM displaying a well‐separated two‐step relaxation process with the anisotropic centers in fine‐tuned local environments was elaborately designed. For the first time a one‐to‐one relationship between the metal sites and the relaxation processes was evidenced. This work sheds light on complex multiple relaxation and may direct the rational design of lanthanide SMMs with enhanced magnetic properties.     

Mesoporous chitosan‐immobilized iron tetrakis(4‐carboxyphenyl)porphyrin as a model of cytochrome P‐450 enzyme for oxidation of ethylbenzene

Mesoporous chitosan‐grafted iron tetra (4‐carboxyphenyl) porphyrin catalyst (Fe TCPP/mesp‐CTS) was prepared and investigated as a practical model for the nano‐cavity and coordinate regulation‐catalysis(CRC) function in cytochrome P‐450 enzyme. Fe TCPP/mesp‐CTS was characterized by X‐ray Diffraction (XRD), Thermogravimetry (TG), Ultraviolet–visible spectroscopy(UV‐Vis), Ultraviolet–visible– Diffuse reflectance spectroscopy (UV‐DRS), Scanning electron microscope (SEM), Fourier transform infrared spectroscopy (FT‐IR), and X‐ray photoelectron spectroscopy (XPS) techniques. The catalytic activity of Fe TCPP/mesp‐CTS for ethylbenzene oxidation was investigated and it was proved to be a better catalyst than Fe TCPP/macp‐CTS based on the ethylbenzene conversion, turnover numbers(TON), and the reusability. These results are attributed to the mesocavity and CRC of amino group in Fe TCPP/mesp‐CTS. The highest ethylbenzene conversion and yields of ketone and alcohol were 24.4% and 18.2%, respectively.     

Efficient Synthesis of Spirooxindole Pyrrolones by a Rhodium(III)‐Catalyzed C−H Activation/Carbene Insertion/Lossen Rearrangement Sequence

A rhodium(III)‐catalyzed domino annulation of simple olefins with diazo oxindoles to give spirooxindole pyrrolone products is described. This reaction can be formally viewed as the result of an anomalous tandem C?H activation, carbene insertion, Lossen rearrangement, and a nucleophilic addition process. The potential utility of this reaction was further demonstrated by the late‐stage diversification of drug molecules.