In the quest for mass production of hydrogen from water electrolysis, to develop highly efficient, stable and low-cost catalysts is still the central challenge.

The layered titanium oxide is a useful and unique precursor for the facile and rapid preparation of the peroxide layered titanium oxide H1.07Ti1.73O4·nH2O (HTO) crystal with enhanced visible light photoactivity. The H2O2 molecules as peroxide chemicals rapidly enter into the interlayers of HTO crystal, and coordinate with Ti within TiO6 octahedron to form a mass of Ti-O-O coordination bond in the interlayers. The introduction of these Ti-O-O coordination bonds result in lowering the band gap of HTO, and promoting the separation efficiency of the photo induced electron–hole pairs. Meanwhile, the photocatalytic investigation indicates that such peroxide HTO crystal has the enhanced photocatalytic performance for RhB degradation and water splitting to generate oxygen under visible light irradiating.

We demonstrate a facile approach to constructing aggregation induced emission (AIE) fluorescent vesicles assembled using a PEG-POSS-(TPE)7 polymer. The narrow wall thickness provides an ideal confined space for creating fluorescence resonance energy transfer (FRET) systems between TPE donors and encapsulated FITC or DOX acceptors.

A highly reactive thiourea-contained polycondensate, poly(dihydropyrimidin-2(1H)-thione) (poly-(DHPMT)) has been facilely synthesized via the Biginelli polycondensation using thiourea and a difunctional compound containing benzaldehyde and β-keto ester groups as monomers. The thiourea moiety in the polymer structure has similar reactivity as the thiourea, thus the poly(DHPMT) is an excellent polymer precusor for preparing new functional polymers through the postpolymerization modification (PPM) strategy. After simple reaction with functional haloalkanes, the parent poly(DHPMT) could be almost completely converted (>99%) to daughter polymers containing alkene or alkyne side groups. Then, the daughter polymers have been further transferred to granddaughter polymers through another PPM via thiol− ene or Cu(I)-catalyzed azide−alkyne cycloaddition (CuAAC) reactions. Besides, when 3-phenylpropargyl chloride was used as the reactant, a bright yellow fluorescent polymer could be simply achieved due to the in situ formed conjugated heterocycle in the polymer structure, further demonstrating the diversity of the functional polymers through PPM. Considering the easily available monomers, simple polycondensation, and the excellent reactivity of the thiourea moiety in the polymer structure, this thiourea-contained Biginilli polycondensate might be a versatile platform for new functional polymer preparation.S ince the middle of the twentieth century, the concept of a macromolecule has been formally accepted, and many strategies have been successfully developed to prepare polymers with designed functions. Among them, postpolymerization modification (PPM) might be one of the most important to prepare new functional polymers by modifying the reactive chain ends or side chains of polymer precursors. 1−5 The history of PPM could actually date back to 1840 when Hancock and Ludersdorf independently reported the first PPM by treating natural rubber with sulfur to produce a tough and elastic material. 6,7 Until now, some large-scale manufactured polymers, such as poly(vinyl alcohol) (PVA), chitosan, some functional resins, etc., are still produced through the PPM strategy. However, traditional modification reactions normally have low efficiency and are easily hampered by the steric hindrance of giant polymer chains, leading to polymers with undefined structure and properties. PPM has therefore been overshadowed by other strategies to synthesize clearly structured polymers. 8−11With the recent development of modern efficient modular reactions, such as the click reactions 12−19 and highly efficient multicomponent reactions (MCRs), 20−34 functional groups can be effectively introduced into the polymer chain once the polymer precursor containing corresponding reactive modules are obtained. 1,35,36 Thus, the PPM strategy has regained attention, and a series of elegant polymers with clear structure have been successfully prepared through this "old" method. 35−39 By now, how to synthesize highly reactive polymer precursors and how to choose e...

Ar hodium(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 CÀHactivation, carbene insertion, Lossen rearrangement, and an ucleophilic addition process.T he potential utility of this reaction was further demonstrated by the late-stage diversification of drug molecules.

An understanding of the photoisomerization mechanism of molecules bound to a metal surface at the molecular scale is required for designing photoswitches at surfaces. It has remained a challenge to correlate the surface structure and isomerization of photoswitches at ambient conditions. Herein, the photoisomerization of a self-assembled monolayer of azobenzene-thiol molecules on a Au surface was investigated using scanning tunneling microscopy and tip-enhanced Raman spectroscopy. The unique signature of the cis isomer at 1525 cm observed in tip-enhanced Raman spectra was clearly distinct from the trans isomer. Furthermore, tip-enhanced Raman images of azobenzene thiols after ultraviolet and blue light irradiation are shown with nanoscale spatial resolution, demonstrating a reversible conformational change. Interestingly, the cis isomers of azobenzene-thiol molecules were preferentially observed at Au grain edges, which is confirmed by density functional theory.

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Biothiols, such as glutathione (GSH), homocysteine (Hcy), and cysteine (Cys), coexist in biological systems with diverse biological roles. Thus, analytical techniques that can detect, quantify, and distinguish between multiple biothiols are desirable but challenging. Herein, we demonstrate the simultaneous detection and quantitation of multiple biothiols, including up to three different biothiols in a single sample, using electron paramagnetic resonance (EPR) spectroscopy and a trityl‐radical‐based probe (MTST). We term this technique EPR thiol‐trapping. MTST could trap thiols through its methanethiosulfonate group to form the corresponding disulfide conjugate with an EPR spectrum characteristic of the trapped thiol. MTST was used to investigate effects of l‐buthionine sulfoximine (BSO) and pyrrolidine dithiocarbamate (PDTC) on the efflux of GSH and Cys from HepG2 cells.