The phosphoric acid-based metakaolin geopolymers were prepared by regulating H 3 PO 4 /Al 2 O 3 ratios. X-ray diffraction (XRD), thermogravimetry and differential scanning calorimeter (TG-DSC), Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM) were used to determine the reaction process and phase formation. The results showed that the metakaolin calcined from Kaolinite mainly consisted of quartz crystalline phase and amorphous phase. The diffraction peak for quartz obviously became lower with the increasing of H 3 PO 4 /Al 2 O 3 ratios. The excessive quartz from metakaolin did not totally take part in the chemical reaction. The polymeric structure of -P-O-Si-O-Al-O constitutes the main building block of phosphoric acid-based metakaolin geopolymeric structure. The optimized compressive strength was 29 AE 2 MPa with H 3 PO 4 /Al 2 O 3 molar ratio ¼ 1.3:1. The simulation of the total deformation under 29 MPa load and the total heat flux at 1400 C of the phosphoric acid-based metakaolin geopolymers with H 3 PO 4 /Al 2 O 3 molar ratio of 1.3:1 based on finite element method verified the failure mechanism and the excellent thermal stability at high temperature.

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Triacetone triperoxide (TATP) is a new terrorist explosive, and most nitrogen-based sensors fail to detect TATP. Herein, a sea urchin-like TiO2-covered TiO2 nanoarray is constructed as a TATP-sensitive homojunction (HJ) by one step hydrothermal method. By taking fluorine-doped tin oxide (FTO) and indium tin oxide (ITO) conducting glass as the substrate, the conducting glass is horizontally and vertically put in the reactor to epitaxially grow TiO2–FTO, TiO2–ITO, TiO2–FTO–HJ and TiO2–ITO–HJ. TiO2–FTO–HJ shows a broad absorption band edge in the visible region and high sensitivity to TATP under the simulating natural light compared with TiO2–FTO, TiO2–ITO, and TiO2–ITO–HJ. E-field intensity distribution simulation reveals that constructing homojunctions between the urchin-shaped TiO2 nanosphere and TiO2 nanoarrays can enhance the localized electromagnetic field intensity at the interface of junctions, which may provide photocatalysis active sites to reduce TATP molecules by promoting charge separation. Moreover, the TiO2–FTO–HJ shows high selectivity to TATP among ammonium nitrate, urea and sulfur, which are common homemade explosive raw materials.

Building novel functional nanomaterials with a polymer is one of the most dynamic research fields at present. Here, three amphiphilic block copolymers of 8-hydroxyquinoline derivative motifs (MQ) with excellent coordination function were synthesized by Reversible Addition-Fragmentation Chain Transfer Polymerization (RAFT) polymerization. The coordination micelles were prepared through the self-assembly process, which the MQ motifs were dispersed in the hydrophobic polystyrene (PSt) blocks and hydrophilic Poly(N-isopropylacrylamide (PNIPAM)) blocks, respectively. The dual-emission micelles including the intrinsic red light emission of quantum dots (QDs) and the coordination green light emission of Zn2+-MQ complexes were built by introducing the CdSe/ZnS and CdTe/ZnS QDs in the core and shell precisely in the coordination micelles through the coordination-driven self-assembly process. Furthermore, based on the principle of three primary colors that produce white light emission, vinyl carbazole units (Polyvinyl Carbazole, PVK) with blue light emission were introduced into the hydrophilic PNIPAM blocks to construct the white light micelles that possess special multi-emission properties in which the intrinsic red light emission of QDs, the coordination green light of Zn2+-MQ complexes, and the blue light emission of PVK were synergized. The dual and multi-emission hybrid micelles have great application prospects in ratiometric fluorescent probes and biomarkers.

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