An effective, template-free synthesis methodology has been developed for preparing mesoporous nitrogen-doped SrTiO 3 (meso-STON) using glycine as both a nitrogen source and a mesopore creator. The N-doping, large surface area and developed porosity endow meso-STON with excellent activity in visible-light-responsive photodegradation of organic dyes.The exceptional electro-optical properties and physicochemical stability of the perovskite SrTiO 3 (STO) give rise to its attractive performance in photocatalytic applications of solar power, including photocatalytic degradation of organic pollutants, water splitting and photoreduction of CO 2 .1-3 However, the intrinsic large bandgap energy (E g = 3.2 eV) of SrTiO 3 allows only the utilization of UV light, encompassing approximately 5.0% energy of the sunlight. 4 A variety of transition metals (TM) have been doped into a STO's crystal matrix in efforts to tune its electronic bandgap for harvesting visible light. 5,6Unfortunately, TM-doping can also bring about either phase impurity or fast recombination of photogenerated charge carriers. Nonmetal-doping represents another effective strategy to realize visible-light response.7-9 Indeed, it was found that N-doped SrTiO 3 (SrTiO 3Àx N x , STON) exhibited excellent photoreactivity and stability under visible-light irradiation. 10Mesoporous-structured photocatalysts are highly desirable in photocatalysis since their large specific surface area (SSA) and mesoporous channels greatly facilitate adsorption, diffusion and surface reaction of the reactants.11 STO perovskite belongs to the cubic crystal system, and typically has low SSA and poor porosity. Moreover, the porosity of STO could be further destroyed by the known processes of nitriding STO to STON. 5,12Although mesoporous STO has been prepared via templatedirected synthesis using various soft (e.g. surfactant or polymer 13 ) and hard (e.g. inorganic salts 14 ) templates, the synthesis of mesoporous STON has rarely been achieved.Here we report a novel, template-free synthesis methodology to prepare mesoporous STON using glycine as both a nitrogen source and a mesopore creator. Aqueous solution of glycine and Sr(NO 3 ) 2 was dropped into ethanol solution of titanium butoxide under stirring, followed by solvent evaporation and subsequent calcinations at 550 1C for 2 hours. The obtained STON was characterized by XRD, TEM, FTIR, UV-vis, and XPS techniques and used for the photodegradation of three refractory organic dyes under visible-light irradiation.Only a strong single peak appears in the small angle XRD pattern (Fig. 1) of the STON sample, suggesting that it possesses disordered wormlike mesopores. 15 The TEM image in Fig. 2A nicely confirms such mesoporosity. The HRTEM image inserted in Fig. 2A reveals that the walls of the mesopores are comprised of single crystal perovskite STON. The labelled lattice distances are consistent with those of (100) and (110) diffractions obtained from XRD tests (Fig. S1, ESIw). In contrast, the STO sample presents poor mesoporous featu...

No abstract

Cis-dichlorodiammineplatinum(II) (CDDP, cisplatin), a widely used anticancer drug, is successfully loaded onto nanodiamond (ND) by adsorption and complexation. The CDDP-ND composite is characterized by IR spectroscopy, atomic absorption spectroscopy, thermogravimetric analysis, energy-dispersive X-ray spectroscopy, and X-ray photoelectron spectroscopy. CDDP is released from the composite in phosphate-buffered saline (PBS) of pH 6.0 at a rate higher than in PBS of pH 7.4. Therefore, it is predicted that the ND vehicle would deliver low concentrations of CDDP in the blood, but release much more drug after integration into the acidic cytoplasm, thereby reducing toxic side effects. The complexation between CDDP and the carboxyl groups on the ND surface is responsible for the pH-responsive release property. The drug released from the composite retains the same cytotoxicity as free CDDP against human cervical cancer cells.

No abstract

In this paper, for the first time, the boundary element method (BEM) is used for modelling smart structures instrumented with piezoelectric actuators and sensors. The host structure and its cracks are formulated with the 3D dual boundary element method (DBEM), and the modelling of the piezoelectric transducers implements a 3D semi-analytical finite element approach. The elastodynamic analysis of the structure is performed in the Laplace domain and the time history is obtained by inverse Laplace transform. The sensor signals obtained from BEM simulations show excellent agreement with those from FEM simulations and experiments. This work provides an alternative methodology for modelling smart structures in structural health monitoring (SHM) applications.

Novel thiourethane bridged polysilsesquioxane aerogels prepared by a sol–gel process and vacuum drying method exhibit extraordinary mechanical properties and low thermal conductivity.

According to the International Energy Agency, biorefinery is “the sustainable processing of biomass into a spectrum of marketable bio-based products (chemicals, materials) and bioenergy (fuels, power, heat)”. In this review, we survey how the biorefinery approach can be applied to highly porous and nanostructured materials, namely aerogels. Historically, aerogels were first developed using inorganic matter. Subsequently, synthetic polymers were also employed. At the beginning of the 21st century, new aerogels were created based on biomass. Which sources of biomass can be used to make aerogels and how? This review answers these questions, paying special attention to bio-aerogels’ environmental and biomedical applications. The article is a result of fruitful exchanges in the frame of the European project COST Action “CA 18125 AERoGELS: Advanced Engineering and Research of aeroGels for Environment and Life Sciences”.

No abstract