Vectored non-covalent interactions—mainly hydrogen bonding and aromatic interactions—extensively contribute to(bio)-organic self-assembling processes and significantly impact the physicochemical properties of the as...Vectored non-covalent interactions—mainly hydrogen bonding and aromatic interactions—extensively contribute to(bio)-organic self-assembling processes and significantly impact the physicochemical properties of the associated superstructures.However,vectored non-covalent interaction-driven assembly occursmainly along one-dimensional(1D)or three-dimensional(3D)directions,and a two-dimensional(2D)orientation,especially that of multilayered,graphene-like assembly,has been reported less.In this present research,by introducing amino,hydroxyl,and phenyl moieties to the triazine skeleton,supramolecular layered assembly is achieved by vectored non-covalent interactions.The planar hydrogen bonding network results in high stability,with a thermal sustainability of up to about 330°C and a Young’s modulus of up to about 40 GPa.Upon introducing wrinkles by biased hydrogen bonding or aromatic interactions to disturb the planar organization,the stability attenuates.However,the intertwined aromatic interactions prompt a red edge excitation shift effect inside the assemblies,inducing broad-spectrum fluorescence covering nearly the entire visible light region(400–650 nm).We show that bionic,superhydrophobic,pillar-like arrays with contact angles of up to about 170°can be engineered by aromatic interactions using a physical vapor deposition approach,which cannot be realized through hydrogen bonding.Our findings show the feasibility of 2D assembly with engineerable properties by modulating vectored non-covalent interactions.展开更多
Polystyrene （PS） @SiO2 core-shell microbeads with large pore and large particle size were prepared via layer-by-layer（LBL）assembly technique for potential applications in nano-micro composites. Negative silica nan...Polystyrene （PS） @SiO2 core-shell microbeads with large pore and large particle size were prepared via layer-by-layer（LBL）assembly technique for potential applications in nano-micro composites. Negative silica nanoparticles synthesized via modified St6ber method and cationic poly （diallyldimethylammonium chloride） were alternately adsorbed on the surface of microbeads. Zeta potential, size, and morphology of the microbeads were monitored during LBL assembly process to ensure the successful deposition of silica nanoparticles. The porous shell was characterized using nitrogen adsorption and desorption analyses, and the surface area, volume and diame- ter of the pores were derived. It is found that the porous shell thickness and the pore size can be tuned by changing the coating times of silica nanoparticles. Finally, PS@SiO2 core-shell microbeads with 5 grn PS solid core and 350 nm mesoporous shell （mean BJH pore diameter is ~27 nm） were used to load CdSe/ZnS quantum dots （QDs）. The fluorescence microscopic image and the optical amplification of the QDs-embedded microbeads （QDBs） indicate that the as-prepared core-shell microbeads can provide adequate space for QDs and may be useful for further application of nano-micro composites.展开更多
To achieve a stable, sensitive, and high-efficiency biological probe, a novel NaYF4：Yb,Er nanocrystals/TiO2 inverse opal composite film was designed by self-assembly and solvent evaporation methods. 32-fold enhanced ...To achieve a stable, sensitive, and high-efficiency biological probe, a novel NaYF4：Yb,Er nanocrystals/TiO2 inverse opal composite film was designed by self-assembly and solvent evaporation methods. 32-fold enhanced upconversion（UC） emission was investigated under 980 nm excitation. According to size-dependency, excitation power density-dependency as well as photonic stop band（PSB）-dependency upconversion spectra, the enhancement mechanism of the composite film was put down to the stochastical diffraction of IOPCs multi-layered structure to the excitation laser. On the basis of the enhancement effect of the composite film, energy transfer between upconversion nanoparticles（UCNPs） and quantum dots（QDs）, and the sensitive sensing of CdTe QDs on mercury, the UC composite film was used for sensing of Hg^2＋ in serum. The solid sensor as a mercury detector owns lots of superiorities such as feasible operation, good linear relationship（R=0.997）, low limit of detection（70.5 nmol/L） and thus may have broad prospects in the biosensing field.展开更多
基金supported by the Fund for Creative Research Groups of National Natural Science Foundation of China (No. 51821093)the National Natural Science Foundation of China (Nos. 52175551, 52075484)(KT and DM)+2 种基金the National Key Research and Development Program (SQ2021YFE010405)(KT)Science Foundation Ireland (SFI) through awards Nos. 15/CDA/3491and 12/RC/2275_P2 (DT)computing resources at the SFI/Higher Education Authority Irish Center for High-End Computing (ICHEC)(SG and DT)
文摘Vectored non-covalent interactions—mainly hydrogen bonding and aromatic interactions—extensively contribute to(bio)-organic self-assembling processes and significantly impact the physicochemical properties of the associated superstructures.However,vectored non-covalent interaction-driven assembly occursmainly along one-dimensional(1D)or three-dimensional(3D)directions,and a two-dimensional(2D)orientation,especially that of multilayered,graphene-like assembly,has been reported less.In this present research,by introducing amino,hydroxyl,and phenyl moieties to the triazine skeleton,supramolecular layered assembly is achieved by vectored non-covalent interactions.The planar hydrogen bonding network results in high stability,with a thermal sustainability of up to about 330°C and a Young’s modulus of up to about 40 GPa.Upon introducing wrinkles by biased hydrogen bonding or aromatic interactions to disturb the planar organization,the stability attenuates.However,the intertwined aromatic interactions prompt a red edge excitation shift effect inside the assemblies,inducing broad-spectrum fluorescence covering nearly the entire visible light region(400–650 nm).We show that bionic,superhydrophobic,pillar-like arrays with contact angles of up to about 170°can be engineered by aromatic interactions using a physical vapor deposition approach,which cannot be realized through hydrogen bonding.Our findings show the feasibility of 2D assembly with engineerable properties by modulating vectored non-covalent interactions.
基金Supported by the National Natural Science Foundation of China(No.51202160)
文摘Polystyrene （PS） @SiO2 core-shell microbeads with large pore and large particle size were prepared via layer-by-layer（LBL）assembly technique for potential applications in nano-micro composites. Negative silica nanoparticles synthesized via modified St6ber method and cationic poly （diallyldimethylammonium chloride） were alternately adsorbed on the surface of microbeads. Zeta potential, size, and morphology of the microbeads were monitored during LBL assembly process to ensure the successful deposition of silica nanoparticles. The porous shell was characterized using nitrogen adsorption and desorption analyses, and the surface area, volume and diame- ter of the pores were derived. It is found that the porous shell thickness and the pore size can be tuned by changing the coating times of silica nanoparticles. Finally, PS@SiO2 core-shell microbeads with 5 grn PS solid core and 350 nm mesoporous shell （mean BJH pore diameter is ~27 nm） were used to load CdSe/ZnS quantum dots （QDs）. The fluorescence microscopic image and the optical amplification of the QDs-embedded microbeads （QDBs） indicate that the as-prepared core-shell microbeads can provide adequate space for QDs and may be useful for further application of nano-micro composites.
基金Project supported by National Natural Science Foundation of China(11374044)Fundamental Research Funds for the Central Universities(3132016333,3132017058)+1 种基金Doctor Start-up Funds of Liaoning Province(201601067)China Postdoctoral Science Foundation(2016M591420)
文摘To achieve a stable, sensitive, and high-efficiency biological probe, a novel NaYF4：Yb,Er nanocrystals/TiO2 inverse opal composite film was designed by self-assembly and solvent evaporation methods. 32-fold enhanced upconversion（UC） emission was investigated under 980 nm excitation. According to size-dependency, excitation power density-dependency as well as photonic stop band（PSB）-dependency upconversion spectra, the enhancement mechanism of the composite film was put down to the stochastical diffraction of IOPCs multi-layered structure to the excitation laser. On the basis of the enhancement effect of the composite film, energy transfer between upconversion nanoparticles（UCNPs） and quantum dots（QDs）, and the sensitive sensing of CdTe QDs on mercury, the UC composite film was used for sensing of Hg^2＋ in serum. The solid sensor as a mercury detector owns lots of superiorities such as feasible operation, good linear relationship（R=0.997）, low limit of detection（70.5 nmol/L） and thus may have broad prospects in the biosensing field.
