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Fluorescent carbon dots (CDs) have drawn significant attention due to their variable species and intriguing optical properties; however, spectrally tuning the fluorescence color of CDs, especially in a long-wavelength region, is still a challenge. In this study, CDs were synthesized through the hydrothermal reaction of 2,5-diaminobenzenesulfonate (DBS) and dodecyl sulfate (DS) in the confined interlayer space of layered double hydroxides (LDHs). Particularly, the emission color of the obtained CD/LDH phosphors could be spectrally tuned from greenish-yellow (λem = 537 nm) to red (λem = 597 nm) by simply changing the molar ratio of the intercalated DBS and DS. Through the detailed characterization of different interlayer CDs by Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy, elemental analysis, and X-ray photoelectron spectroscopy (XPS), a new route of modulating the absorption and emission wavelengths of CDs by regulating the content of graphitic nitrogen during heteroatom doping is presented. In addition, the stabilities of the solid-state luminescence against UV bleaching and temperature variation were improved by the rigid 2-dimensional (2D) LDH matrix, and prospective applications of the proposed CD/LDH phosphors were demonstrated in multicolour displays and in the fabrication of white light-emitting diodes (WLEDs).Photodynamic therapy (PDT) has been extensively used to treat cancer and other malignant diseases because it can offer many unique advantages over other medical treatments such as less invasive, fewer side effects, lower cost, etc. Despite great progress, the efficiency of PDT treatment, as an oxygen-dependent therapy, is still limited by the hypoxic microenvironment in the human tumor region. In this work, we have developed a near-infrared (NIR) activated theranostic nanoplatform based on upconversion nanoparticles (UCNPs), which incorporates PDT photosensitizer (curcumin) and NO donor (Roussin's black salt) in order to overcome hypoxia-associated resistance by reducing cellular respiration with NO presence in the PDT treatment. Our results suggest that the photo-released NO upon NIR illumination can greatly decrease the oxygen consumption rate and hence increase singlet oxygen generation, which ultimately leads to an increased number of cancer cell deaths, especially under hypoxic condition. It is believed that the methodology developed in this study enables to relieve the hypoxia-induced resistance in PDT treatment and also holds great potential for overcoming hypoxia challenges in other oxygen-dependent therapies.Oriented single-domain magnetic nanoparticles with a high remanence ratio Mr/Ms and maximum magnetic energy product (BH)max have attracted immense attention. However, nanoparticles easily agglomerate due to their extremely small size, which impedes the process of orientation. So manipulating the orientation of nanoparticles is still a key challenge. Here, L10-FePt single-domain nanoparticles were successfully synthesized by a chemical method in the liquid phase and nanoparticle-based anisotropic nanocomposites were obtained by dispersing the nanoparticles in liquid epoxy resin under an external magnetic field. The main factors that impact the orientation of L10-FePt single-domain nanoparticles were investigated further. It is found that the dispersibility of nanoparticles has a great impact on the degree of orientation, so do the applied magnetic field and the concentration of nanoparticles. Nanocomposites with homodisperse nanoparticles oriented under a suitable external magnetic field exhibit excellent magnetic performance, such as high coercivity Hc and remanence Mr, which gives the nanocomposites a higher (BH)max than the isotropic samples. The anisotropic nanocomposites show great potential in multifarious permanent magnet applications and fundamental research.To enable high-efficiency solar energy conversion, rational design and preparation of low cost and stable semiconductor photocatalysts with associated co-catalysts are desirable. [https://www.selleckchem.com/products/plx51107.html Selleckchem PLX51107] However preparation of efficient catalytic systems remains a challenge. Here, N-doped TiO2/ternary nickel-zinc nitride (N-TiO2-Ni3ZnN) nanocomposites have been shown to be a multi-functional catalyst for photocatalytic reactions. The particle size of Ni3ZnN can be readily tuned using N-TiO2 nanospheres as the active support. Due to its high conductivity and Pt-like properties, Ni3ZnN promotes charge separation and transfer, as well as reaction kinetics. The material shows co-catalytic performance relevant for multiple reactions, demonstrating its multifunctionality. Density functional theory (DFT) based calculations confirm the intrinsic metallic properties of Ni3ZnN. N-TiO2-Ni3ZnN exhibits evidently improved photocatalytic performances as compared to N-TiO2 under visible light irradiation.The first Fe-catalysed alkylation of 2-methyl and 4-methyl-azaarenes with a series of alkyl and hetero-aryl alcohols is reported (&gt;39 examples and up to 95% yield). Multi-functionalisation of pyrazines and synthesis of anti-malarial drug (±) Angustureine significantly broaden the scope of this methodology. Preliminary mechanistic investigation, deuterium labeling and kinetic experiments including trapping of the enamine intermediate 1a' are of special importance.Graphene nanobubbles (GNBs) have become the subject of recent research due to their novel physical properties. However, present methods to create them involve either extreme conditions or complex sample fabrication. We present a novel approach which relies on the intercalation of small molecules (NH3), their surface-mediated decomposition and the formation of larger molecules (N2) which are then entrapped beneath the graphene in bubbles. Our hypothesised reaction mechanism requires the copper substrate, on which our graphene is grown via chemical vapour deposition (CVD), to be oxidised before the reaction can occur. This was confirmed through X-ray photoelectron spectroscopy (XPS) data of both oxidised and reduced Cu substrate samples. The GNBs have been analysed through atomic force microscopy (AFM, after NH3 treatment) and XPS, which reveals the formation of five distinct N 1s peaks, attributed to N2 entrapment, N doping species and atomic nitrogen bonded with the Cu within the substrate. This method is simple, occurs at low temperatures (520 K) and integrates very easily with conventional CVD graphene growth, so presents an opportunity to open up this field of research further.