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Here we developed an ensemble of Nickel-Based nano-Composites (NBCs) to investigate the branching phenomena in solution-phase synthesis with precision and in depth.

Two effective processes have been developed for the preparation of sitagliptin phosphate. The approach of chemical resolution obtained R-sitagliptin in five steps from commercially available starting materials using the inexpensive NaBH4 to reduce the enamine and then using (−)-di-p-toluoyl-L-tartaric acid to resolve racemates in 11% yield overall. The route successfully avoids the use of expensive noble metal as catalysts compared with traditional synthesis methods, resulting in greatly reduced costs and simplified synthetic routes. Other alternative asymmetric hydrogenation of β-ketomide routes for the synthesis of sitagliptin were found, two of the intermediates were synthesized for the first time.

Driven by excellent CO oxidation capability of gold nanoparticles at room temperature, a TiO2 supported Au nanoparticles (Au/TiO2) is synthesized by deposition-precipitation with urea (DPU). To solve the sintering issue of gold nanoparticles during activation process, atmospheric-pressure cold O2 plasma is employed to activate the Au/TiO2 catalysts and compared with the conventional calcination. The plasma activated one (S-P) shows poorer activity compared to the calcined one (S-C). However, S-P with further TPD treatment (S-PT) shows the best catalytic activity among above-mentioned samples. To elucidate the plasma effect, TEM, XPS, UV–vis spectroscopy and in situ DRIFTS techniques are used for catalyst characterization. Based on TEM results, S-P sample has smaller particle size and narrower size distribution compared to S-C sample, while the high content of low-coordinated Au atoms and the poisoning nitrate species over S-P are revealed by in situ DRIFTS. Upon further TPD treatment, the poisoning species occupying the active sites is desorbed from catalyst surface and the improvements in Au particle size and size distribution are maintained. The mechanism for plasma effect on activation of Au/TiO2 prepared by DPU is also discussed.

N-doped TiO2 was synthesized by a facile so-gel method using urea as nitrogen resource. To seek the efficient N doping of TiO2 photocatalysts, non-thermal N2 plasma was employed to treat N-doped TiO2 followed by calcination (N-TiO2 (NTP)) and compared with the conventional calcination (N-TiO2). The samples were evaluated under visible light irradiation for photocatalytic degradation of methyl orange (MO). To elucidate the plasma treatment effect, XRD, SEM, EDS, TEM, BET, UV–vis DRS, FT-IR and XPS techniques were used for catalyst characterization. N-TiO2 (NTP) possessed small particle size of 4.9 nm with better dispersion and narrow band gap of 1.6 eV. The visible-light photocatalytic activity of N-TiO2 (NTP) was much better than that of N-TiO2. And the photocatalytic degradation kinetics of the MO fitted with the Langmuir-Hinshelwood equation. The apparent reaction rate constant of N-TiO2 (NTP) was about 2.8 times as high as that of N-TiO2. The enhancement was ascribed to small particle size of N-doped TiO2 offering more surface active sites and high content of surface oxygen.

Here, we prepared Bi-metal modified defective Bi5O7Br nanotubes (Bi/Bi5O7Br–OV) by hydrothermal synthesis to be an efficient photocatalyst. Density function theory (DFT) revealed that oxygen vacancies in Bi5O7Br could form an intermediate level, which could allow electron transfer to a new intermediate level, and finally move to the conduction band. The Bi/Bi5O7Br–OV nanotubes demonstrate superior photocatalytic degradation of phenol, showing 3 times higher than that of pristine Bi5O7Br. The defects and Bi endow Bi5O7Br nanotubes with abundant active sites and improve the solar absorption. The increased and more dispersed charge density allow enhanced electronic conductivity and the separation of photogenerated carriers. Furthermore, more ·OH radicals are generated during photochemical reaction, which is beneficial in improving the photocatalytic performance. This work will play significant roles and create opportunities in modifying Bi-based materials for promoting photocatalysis.

SnS2 material is considered as a promising anode material for Na-ion batteries (NIBs) because of its unique layered structure and high theoretical capacity. However, SnS2 nanosheets are easily overlapped during synthesis and cycling process. Also, they have to experience large volume change during repeated sodiation-desodiation processes. A promising concept is the application of hierarchical hollow structures for improving electrode stability upon cycling. However, they usually rely on template methods that require complex procedures such as chemical etching or calcination to remove inner template. Here, we demonstrate a simple and innovative strategy for fabricating the SnS2 nanosheets assembled hierarchical tubular structures (SnS2 NS ⊂ HTSs) by using cobalt-nitrilotriacetic acid chelate nanowires as soluble template, which makes shell growth and core template dissolution occur simultaneously in one step reaction. Owing to the hollow interior and well separated nanosheets with maximally exposed edges, the SnS2 NS ⊂ HTSs exhibit excellent electrochemical performance. When evaluated as the anode material for NIBs, it delivers a high discharge capacity of 708 mAh g−1 at 50 mA g−1 and still remains up to 414 mAh g−1 after 50 cycles.

Activation of chrysocolla by organic Cu-chelating agents was studied using flotation tests, instrumental analytical techniques, and computational methods, revealing that the performance of these agents was related to their chemical activity and chrysocolla dissolution properties. The above activation was mainly ascribed to the high chemical activity of organic chelators, which significantly increased collector adsorption capacity.

One of the main drawbacks with applying the most promising electrode materials in lithium-ion batteries is their intrinsic poor electronic conductivity. Many approaches which include mixing them with good electrical conductors have been developed to solve this problem, yet they do not improve the lattice electronic conductivity within the crystal. Here we present a one-step hydrothermal route for fabricating the core–shell heterostructures through sequential growth of the core and shell materials. The cores are Nb-doped TiO2 rods with improved conductivity that can deliver high capacity, yet the Nb2O5 nanosheets shells can act as a protective layer to prevent electrode dissolution and maintain the electrode integrity over long term cycles and contribute additional lithium storage capacity. When employed as an anode material in lithium-ion batteries, it exhibits an outstanding cycle stability of 189 mA h g−1 at 170 mA g−1 for more than 700 cycles. This work provides an important strategy to improve the conductivity of the host and construct a protective layer by simply adding a guest ion in reaction.

The search for a facile and energy-saving nanomaterial fabrication technology is of great significance in the area of energy conversion and storage. However, most approaches require high temperature heat treatment to transform nanomaterials from amorphous to crystalline phase or improve their crystallinity. This paper reports a hydrothermal approach for the synthesis of well-crystallized CuO hierarchical structures assembled by intercrossed nanosheets. Time dependent experiments suggest that CuO hierarchical structures followed a rapid nucleation and crystal growth mechanism. Therefore, well-crystallized CuO hierarchical structures can be directly applied as anode for lithium-ion batteries without further calcination. The results show that the uncalcined CuO hierarchical structures could deliver discharge capacities of 575 mA h g−1 at 1C over 100 cycles and 504 mA h g−1 at 2C over 100 cycles, respectively, which were much better than those of calcined ones. This excellent performance can be ascribed to a synergistic effect of their high crystallinity and hierarchical structure containing micro and nano features.

A promising new concept is to apply additive/binder-free electrodes for lithium-ion batteries by directly growing active materials on current collectors, however, they still suffer from the low quality electronic contact and poor mechanical stability due to the lattice mismatch between active materials and substrates. Here we present the direct growth of vertically aligned MoS2 nanosheets on a Ti substrate through a self-supported TiO2 bonding interface route, thereby preferentially exposing the edges on the film surface. In this unique structure, MoS2 nanosheets are interconnected with each other and create a strong adhesion to the Ti substrate through the TiO2 bonding interface, which would allow electrons to easily transport throughout the whole electrode. Furthermore, their edge-terminated structure can provide more sites for Li-ion intercalation. By using this additive/binder-free electrode, it can deliver a discharge capacity as high as 1189 mA h g−1 at a current density of 1000 mA g−1 after 600 cycles. Importantly, our synthetic approach, based on this metal surface dissolution–crystallization produced bonding interface, can provide a general strategy for the direct growth of other metal sulphides such as NiS and CoS nanosheets on the Ti substrate with great promise for various applications.

Transition metal oxides are very promising anode materials for high-performance lithium-ion batteries (LIBs). However, they experience large volume expansion upon cycling, resulting in electrode pulverization and poor cycling stability. Here, we demonstrate a rational design and synthesis of graphene-wrapped ZnO nanotubes, and graphene oxide nanosheets in the reaction form a “soft” sealing layer to confine the crystal growth within a small space, which enables the nanotubes to be tightly bound with the graphene matrix. It is interesting to find that electrode pulverization upon cycling is not so much a drawback but a blessing in disguise, which reconstructs the starting nanotubes into quantum dots with an average size of ∼2.3 nm within the graphene matrix in the form of a tubular structure. The formed quantum dots not only provide a high contact area with the electrolyte but also shorten the solid-phase ion diffusion. Meanwhile, the graphene nanosheets are still tightly bound with the quantum dot assembled tubular structure, which can accommodate volume change and facilitate efficient electron transport and lithium-ion diffusion in electrodes. When used as an anode in LIBs, they demonstrate excellent cycling stability with a high reversible specific capacity of 891 mA h g−1 over 1000 cycles at 2000 mA g−1.

Synthesis of methylated epigallocatechin gallate from (–)-epigallocatechin gallate and propylgallate was accomplished using a benzyl (Bn) group as a protecting group for phenols. This methodology provided (–)-epigallocatechin-3-(4-O-methylgallate), which are naturally scarce catechin derivatives.

Here we report a facile and environmentally friendly approach for the synthesis of CuO submicron rods through the polymer-assisted oriented attachment of nanocrystal building blocks along with calcination. The results show that the CuO submicron rods were formed with average diameter of 543 nm and length of 23.9 μm, giving a high aspect ratio of 44, which would enhance electron transfer and lithium ion diffusion rates. When CuO submicron rods were applied as an anode material in lithium-ion batteries, they can deliver a discharge capacity as high as 243 mA h g−1 at current density of 670 mA g−1 after 70 cycles.

Ferroferric oxide, Fe3O4, is a highly promising anode material for lithium-ion batteries (LIBs) owing to its excellent electrochemical properties. High resolution transmission electron microscopy (HRTEM) was used to correlate the morphological features of the Fe3O4 nanoparticles (NPs) with their electrochemical properties. The co-precipitately synthesized Fe3O4 NPs were composed of 14-facet truncated octahedrons containing 6 {100} and 8 {111} planes, and 26-facet polyhedrons containing 6 {100}, 12 {110} and 8 {111} planes, indicating that the shape of NPs is changeable from 14-facet truncated octahedrons to 26-facet polyhedrons. As the anode for LIBs, the NPs delivered a high initial discharge capacity of 1067 mA h g−1, which could be attributed to their small size and abundant exposure of edges and corners in the multi-faceted polyhedral structures, offering low-coordinated atoms that act as active sites for lithium storage.

In this work, we report the facile synthesis of Fe3O4/reduced graphene oxide (RGO) nanocomposites and their improved lithium storage capability. Fe3O4/RGO composites synthesized by a facile co-precipitation method exhibited outstanding electrochemical performance with good cycling stability. As an anode material for lithium ion batteries (LIBs), the Fe3O4/RGO composites achieved a high reversible capacity of 1637 mA h g−1 (0.1 A g−1) at the 10th cycle, which still remained at 1397 mA h g−1 after 100 cycles. Moreover, the Fe3O4/RGO composites have excellent rate capability. Characterization results reveal that such a large reversible capacity is attributed to the synergistic effect between Fe3O4 and RGO, with the Fe3O4 nanoparticles (NPs) with surface step atoms offering abundant electrochemical active sites for lithium storage. In addition, RGO acts as a volume buffer and electron conductor, and more importantly preserves the electrochemically active surface and avoids the aggregation of the Fe3O4 NPs.

In this work, we fabricated a lightweight (1.25 g cm−3) N doped reduced graphene (N-RGO) paper through a combined method of vacuum filtration and thermal treatment under an ammonia atmosphere. 0.48% of N has been uniformly incorporated into the graphene sheets, which results in an inherent improvement in conductivity. Simultaneously, the as-fabricated N-RGO paper possesses excellent flexibility without any effect on its electronic properties. Furthermore, the good performance of N-RGO as a supercapacitor electrode was also demonstrated with a high specific capacitance of 280 F g−1 at 5 mV s−1. The N-RGO electrode also exhibited a remarkable long-term cycling stability with 99.4% capacitance retention after 40000 cycles. This work constitutes the first attempt of applying N-doping to improve the electronic properties and electrochemical performance for graphene paper.

In this paper, an environmentally friendly etching system containing H2SO4–MnO2 colloid was used to investigate surface etching for polycarbonate (PC). The effects of swelling condition, H2SO4 concentrations and etching times on surface topography and surface roughness were studied. With the etching treatment, the surface average roughness (R a) of PC substrates increased from 3 to 76 nm and the adhesion strength between the electroless copper and PC substrate reached 1.08 KN/m. Surface chemistry of PC substrates was investigated by the contact angle measurement and X-ray photoelectron spectroscopy spectra (XPS). After the etching treatment, PC surface became hydrophilic and the contact angle decreased from 95.2 to 39.6o. XPS analyses indicate that hydroxyl and carboxyl groups are formed on the PC surface as a result of the etching treatment, which improve the adhesion strength between PC substrate and electroless copper film.

A flexible and solid-state supercapacitor device based on TiO2@C core–shell nanowires has been developed and exhibited excellent flexibility—it can even be folded and twisted without sacrificing electrochemical properties—and good electrochemical performance with a maximum energy density of 0.011 mW h cm−3.

We present a new type of highly hierarchical but nonporous nanostructure with a unique "dandelion" morphology. Based on the time evolution of these Ni3 C nanostructures, we suggest a mechanism for their formation. This type of hierarchical nanocrystal, with high accessible specific surface area in a relatively large (ca. 750 nm overall diameter) stable structure, can be valuable in catalysis and related applications.

Porous Pt-Ni-P composite nanotube arrays (NTAs) on a conductive substrate in good solid contact are successfully synthesized via template-assisted electrodeposition and show high electrochemical activity and long-term stability for methanol electrooxidation. Hollow nanotubular structures, porous nanostructures, and synergistic electronic effects of various elements contribute to the high electrocatalytic performance of porous Pt-Ni-P composite NTA electrocatalysts.

A layer-by-layer assemble method was used to fabricate CdS quantum dots (QDs) sensitized electrodes. Scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), and transmission electron microscopy (TEM) have been utilized to characterize the samples. The absorption spectra and photovoltaic measurement confirmed that much more effective deposition of QDs inTiO2matrix and much better power conversion performance were achieved for these multilayer electrodes compared with the ones fabricated by traditional single-layer assembly method.

Glycogen synthase kinase 3β (GSK-3β) is a potential therapeutic target for cancer, type-2 diabetes, and Alzheimer's disease. This paper proposes a new lead identification protocol that predicts new GSK-3β ATP competitive inhibitors with topologically diverse scaffolds. First, three-dimensional quantitative structure-activity relationship (3D QSAR) models were built and validated. These models are based upon known GSK-3β inhibitors, benzofuran-3-yl-(indol-3-yl) maleimides, by means of comparative molecular field analysis (CoMFA) and comparative molecular similarity indices analysis (CoMSIA). Second, 28 826 maleimide derivatives were selected from the PubChem database. After filtration via Lipinski's rules, 10 429 maleimide derivatives were left. Third, the FlexX-dock program was employed to virtually screen the 10 429 compounds against GSK-3β. This resulted in 617 virtual hits. Fourth, the 3D QSAR models predicted that from the 617 virtual hits, 93 compounds would have GSK-3β inhibition values of less than 15 nM. Finally, from the 93 predicted active hits, 23 compounds were confirmed as GSK-3β inhibitors from literatures; their GSK-3β inhibition ranged from 1.3 to 480 nM. Therefore, the hits rate of our virtual screening protocol is greater than 25%. The protocol combines ligand- and structure-based approaches and therefore validates both approaches and is capable of identifying new hits with topologically diverse scaffolds.

Here we report on the growth of TiO2 nanotube arrays (TNAs) on Ti foil with laser-drilled microhole arrays (MHAs). The MHAs promoted the adhesion of the TNA film to Ti substrate, which is well suited for flexible dye-sensitized solar cells (DSSCs). The MHA photoanode and TNAs were characterized by SEM, 3D optical profiling, XRD and TEM. For such a flexible MHA photoanode, the TNA-based DSSC was assembled using a platinized conductive glass counter electrode, and a conversion efficiency of 3.45% was achieved under AM 1.5 condition. A flexible TNA-based DSSC was also fabricated using a flexible MHA photoanode combined with a platinized indium tin oxide-polyethylene naphthalate counter electrode, which achieved 2.67% photovoltaic conversion efficiency under simulated AM 1.5 sunlight.

To improve the photocatalytic application performances of TiO2, in this work, firstly CdS modified Degussa P25 TiO2 (CdS/TiO2) composites were prepared by two methods, sol–gel method and precipitation method. Next they, sol–gel-CdS/TiO2 (sg-CdS/TiO2) and precipitation-CdS/TiO2 (pp-CdS/TiO2), were loaded on activated carbon fibers (ACFs) by dip-coating method using the sodium carboxymethyl cellulose as adhesives. The composites were characterized by XRD, UV–vis absorbance spectra, SEM, EDS and BET. The photocatalytic activities under sunlight were investigated by the degradation of methylene blue. The results showed that CdS/TiO2 composites were mainly composed of anatase-TiO2 and little CdS cubic phases. The absorption wavelengths of sg-CdS/TiO2 and pp-CdS/TiO2 composites were extended to 590 nm and 740 nm, respectively. The absorption edge had a pronounced ‘red shift’. From EDS analysis, the elemental contents of CdS/TiO2 were mainly Ti and O and a small quantity of S and Cd. CdS/TiO2 loaded on ACFs were in the form of small clusters, but not very uniform; compared with the original ACFs, the surface area and pore volume of CdS/TiO2/ACFs decreased slightly, respectively, while the average pore diameter was not changed. The photodegradation rate of methylene blue under sunlight with CdS/TiO2/ACFs composites was markedly higher than that of P25-TiO2/ACFs, and the effect of pp-CdS/TiO2/ACFs composites was better than that of sg-CdS/TiO2/ACFs, when irradiated for 180 min, and the photodegradation rate of methylene blue reached to 90.1%. The photodegradation kinetics of the methylene blue fitted with the Langmuir–Hinshelwood equation. The apparent reaction rate constants of sg-CdS/TiO2/ACFs and pp-CdS/TiO2 were 0.0105 min−1 and 0.0146 min−1, respectively, which were about 1.3–1.7 times as large as that of P25-TiO2/ACFs.

The controllable electrochemical synthesis of Ce4+-doped ZnO nanostructures from nanotubes to nanorods and nanocages is reported. The electrochemical route for the preparation of Ce4+-doped ZnO nanostructures represents a simple, quick, and economical method. The growth mechanisms for Ce4+-doped ZnO nanotubes, nanorods, and nanocages are proposed here. Ce4+-doped ZnO nanotubes and nanocages formed when the crystal growth was only proceeded on the sides of six (1010) facets of a hexagonal planar nucleus with preferential growth in the (0001) direction. The hexagonal Ce4+-doped ZnO nanorods were formed when the crystal growth proceeded on the whole hexagonal planar nucleus with preferential growth in the (0001) direction. The X-ray diffraction, energy dispersive spectroscopy, X-ray photoelectron spectroscopy, transmission electron microscopy, high-resolution transmission electron microscopy, and selected area electron diffraction were used to characterize the phase, composition, and qualities of the prepar...

A web-like-structured ZnO cluster (WLSZC) has been prepared by applying ultrasonic treatment for 70 min during the co-precipitation process. These samples were subsequently characterized by high-resolution transmission electron microscopy (TEM) and photoluminescence (PL) spectroscopy. In WLSZC, we observed homogeneous polygons, which consist of one single-crystal particle at each side. The PL intensity of the WLSZC is 8–14 times greater than that of nano-particle samples, most likely due to the resonant effect of the polygonal pores (about 100 nm wide). In addition, four blue peaks appeared in the prepared samples indicates that variable defects may be produced during the ultrasonic treatment.

High cholesterol levels contribute to hyperlipidemia. Liver X receptors (LXRs) are the drug targets. LXRs regulate the cholesterol absorption, biosynthesis, transportation, and metabolism. Novel agonists of LXR, especially LXRβ, are attractive solutions for treating hyperlipidemia. In order to discover novel LXRβ agonists, a three-dimensional pharmacophore model was built based upon known LXRβ agonists. The model was validated with a test set, a virtual screening experiment, and the FlexX docking approach. Results show that the model is capable of predicting a LXRβ agonist activity. Ligand-based virtual screening results can be refined by cross-linking by structure-based approaches. This is because two ligands that are mapped in the same way to the same pharmacophore model may have significantly different binding behaviors in the receptor’s binding pocket. This paper reports our approach to identify reliable pharmacophore models through combining both ligand- and structure-based approaches.

As a new graphene derivative, graphene fluoroxide (GFO) has not been fully studied because of its complex preparation process. In this paper, two simple methods, a modified Hummers' method and an improved method, were adopted to oxidize unsaturated commercial graphite fluoride (GIF) to prepare graphite fluoroxide (GIFO), the precursor of GFO. GFO was finally obtained via liquid-phase ultrasonic exfoliation of GIFO in organic solvents. Multiple spectroscopic techniques were used to characterize GIFO and GFO. The test results indicate that both of the two methods can covalently bond oxygen functional groups to graphene fluoride (GF) sheets successfully, but the modified Hummers' method gives higher yield and oxidizability. The structure of the GFO sheet is confirmed as few-layer by its atomic force microscopy results and transmission electron microscopy images. UV-vis and fluorescence emission measurements suggest that introducing oxygen groups into GF sheets can change their optoelectronic properties. Based on this, GFO with tunable optoelectronic properties might be facilely obtained in large batches through oxidization and liquid-phase exfoliation of unsaturated GIF with different fluorine coverage.

In this study, we report a facile one-step solvothermal approach for growing nanoparticle aggregates–texture nanosheets hierarchical TiO2 core–shell structure (HTCSS) via the synergistic interaction of butylamine and ethanol. Under specific conditions, the products obtained in ethanol tended to aggregate into spherical structures, but in butylamine preferred to form nanosheet structures. Optimal cooperation between butylamine and ethanol leads to the formation of a core–shell structure with nanoparticle aggregates as the core and texture nanosheets as the shell. The HTCSSs cover a wide radius range from 150 to 800 nm, which is comparable to the wavelength of visible light. Therefore, they can be effectively used as light scattering materials to improve light harvesting in dye-sensitized solar cells (DSCs). Furthermore, the HTCSSs possess a very high surface area of 228.5 m2 g−1 and main pore size centered at 2.0 nm. DSCs using HTCSSs with bifunctional character of light scattering and high surface area properties showed an photoconversion efficiency of 8.90% under AM1.5 illumination, which was much higher than that derived from P25 nanoparticles of an optimized film thickness (6.09%).