Graphitic Carbon Conformal Coating of Mesoporous TiO₂ Hollow Spheres for High-Performance Lithium Ion Battery Anodes

Rational design and controllable synthesis of TiO₂ based materials with unique microstructure, high reactivity, and excellent electrochemical performance for lithium ion batteries are crucially desired. In this paper, we developed a versatile route to synthesize hollow TiO₂/graphitic carbon (H-TiO₂/GC) spheres with superior electrochemical performance. The as-prepared mesoporous H-TiO₂/GC hollow spheres present a high specific surface area (298 m² g^–1), a high pore volume (0.31 cm³ g^–1), a large pore size (∼5 nm), well-defined hollow structure (monodispersed size of 600 nm and inner diameter of ∼400 nm, shell thickness of 100 nm), and small nanocrystals of anatase TiO₂ (∼8 nm) conformably encapsulated in ultrathin graphitic carbon layers. As a result, the H-TiO₂/GC hollow spheres achieve excellent electrochemical reactivity and stability as an anode material for lithium ion batteries. A high specific capacity of 137 mAh g^–1 can be achieved up to 1000 cycles at a current density of 1 A g^–1 (5 C). We believe that the mesoporous H-TiO₂/GC hollow spheres are expected to be applied as a high-performance electrode material for next generation lithium ion batteries

Achieving <i>In Situ</i> Dynamic Fluorescence in the Solid State through Synergizing Cavities of Macrocycle and Channels of Framework

To achieve in situ dynamic fluorescence in the solid state and unveil the mechanism remain a formidable challenge. Herein, through synergizing the cavities of macrocycles for dynamic complexing and the channels of frameworks for facile transit, we construct intrinsic channels from an emissive cyclophane and realize precisely tunable emission in the solid state through the sequential guests’ exchange. Specifically, two design criteria involve (1) The twisted cyanostilbene units not only endow the systems with solid-state fluorescence but also tailor the π–π interactions in the complex to generate the desired emission and (2) the large cavity of cyclophane results in the formation of ternary complexes with controllable binding affinity which further assemble into robust channels for the guests’ exchange in the bulky state. This strategy unifies the advantages of both macrocycle and framework in one system, achieving visualization, recyclability, and easy processability simultaneously. The present study paves an easy, efficient, and general platform for constructing dynamic optical materials

Achieving <i>In Situ</i> Dynamic Fluorescence in the Solid State through Synergizing Cavities of Macrocycle and Channels of Framework

To achieve in situ dynamic fluorescence in the solid state and unveil the mechanism remain a formidable challenge. Herein, through synergizing the cavities of macrocycles for dynamic complexing and the channels of frameworks for facile transit, we construct intrinsic channels from an emissive cyclophane and realize precisely tunable emission in the solid state through the sequential guests’ exchange. Specifically, two design criteria involve (1) The twisted cyanostilbene units not only endow the systems with solid-state fluorescence but also tailor the π–π interactions in the complex to generate the desired emission and (2) the large cavity of cyclophane results in the formation of ternary complexes with controllable binding affinity which further assemble into robust channels for the guests’ exchange in the bulky state. This strategy unifies the advantages of both macrocycle and framework in one system, achieving visualization, recyclability, and easy processability simultaneously. The present study paves an easy, efficient, and general platform for constructing dynamic optical materials

Achieving <i>In Situ</i> Dynamic Fluorescence in the Solid State through Synergizing Cavities of Macrocycle and Channels of Framework

To achieve in situ dynamic fluorescence in the solid state and unveil the mechanism remain a formidable challenge. Herein, through synergizing the cavities of macrocycles for dynamic complexing and the channels of frameworks for facile transit, we construct intrinsic channels from an emissive cyclophane and realize precisely tunable emission in the solid state through the sequential guests’ exchange. Specifically, two design criteria involve (1) The twisted cyanostilbene units not only endow the systems with solid-state fluorescence but also tailor the π–π interactions in the complex to generate the desired emission and (2) the large cavity of cyclophane results in the formation of ternary complexes with controllable binding affinity which further assemble into robust channels for the guests’ exchange in the bulky state. This strategy unifies the advantages of both macrocycle and framework in one system, achieving visualization, recyclability, and easy processability simultaneously. The present study paves an easy, efficient, and general platform for constructing dynamic optical materials

Achieving <i>In Situ</i> Dynamic Fluorescence in the Solid State through Synergizing Cavities of Macrocycle and Channels of Framework

To achieve in situ dynamic fluorescence in the solid state and unveil the mechanism remain a formidable challenge. Herein, through synergizing the cavities of macrocycles for dynamic complexing and the channels of frameworks for facile transit, we construct intrinsic channels from an emissive cyclophane and realize precisely tunable emission in the solid state through the sequential guests’ exchange. Specifically, two design criteria involve (1) The twisted cyanostilbene units not only endow the systems with solid-state fluorescence but also tailor the π–π interactions in the complex to generate the desired emission and (2) the large cavity of cyclophane results in the formation of ternary complexes with controllable binding affinity which further assemble into robust channels for the guests’ exchange in the bulky state. This strategy unifies the advantages of both macrocycle and framework in one system, achieving visualization, recyclability, and easy processability simultaneously. The present study paves an easy, efficient, and general platform for constructing dynamic optical materials

Achieving <i>In Situ</i> Dynamic Fluorescence in the Solid State through Synergizing Cavities of Macrocycle and Channels of Framework

To achieve in situ dynamic fluorescence in the solid state and unveil the mechanism remain a formidable challenge. Herein, through synergizing the cavities of macrocycles for dynamic complexing and the channels of frameworks for facile transit, we construct intrinsic channels from an emissive cyclophane and realize precisely tunable emission in the solid state through the sequential guests’ exchange. Specifically, two design criteria involve (1) The twisted cyanostilbene units not only endow the systems with solid-state fluorescence but also tailor the π–π interactions in the complex to generate the desired emission and (2) the large cavity of cyclophane results in the formation of ternary complexes with controllable binding affinity which further assemble into robust channels for the guests’ exchange in the bulky state. This strategy unifies the advantages of both macrocycle and framework in one system, achieving visualization, recyclability, and easy processability simultaneously. The present study paves an easy, efficient, and general platform for constructing dynamic optical materials

Achieving <i>In Situ</i> Dynamic Fluorescence in the Solid State through Synergizing Cavities of Macrocycle and Channels of Framework

To achieve in situ dynamic fluorescence in the solid state and unveil the mechanism remain a formidable challenge. Herein, through synergizing the cavities of macrocycles for dynamic complexing and the channels of frameworks for facile transit, we construct intrinsic channels from an emissive cyclophane and realize precisely tunable emission in the solid state through the sequential guests’ exchange. Specifically, two design criteria involve (1) The twisted cyanostilbene units not only endow the systems with solid-state fluorescence but also tailor the π–π interactions in the complex to generate the desired emission and (2) the large cavity of cyclophane results in the formation of ternary complexes with controllable binding affinity which further assemble into robust channels for the guests’ exchange in the bulky state. This strategy unifies the advantages of both macrocycle and framework in one system, achieving visualization, recyclability, and easy processability simultaneously. The present study paves an easy, efficient, and general platform for constructing dynamic optical materials

Achieving <i>In Situ</i> Dynamic Fluorescence in the Solid State through Synergizing Cavities of Macrocycle and Channels of Framework

To achieve in situ dynamic fluorescence in the solid state and unveil the mechanism remain a formidable challenge. Herein, through synergizing the cavities of macrocycles for dynamic complexing and the channels of frameworks for facile transit, we construct intrinsic channels from an emissive cyclophane and realize precisely tunable emission in the solid state through the sequential guests’ exchange. Specifically, two design criteria involve (1) The twisted cyanostilbene units not only endow the systems with solid-state fluorescence but also tailor the π–π interactions in the complex to generate the desired emission and (2) the large cavity of cyclophane results in the formation of ternary complexes with controllable binding affinity which further assemble into robust channels for the guests’ exchange in the bulky state. This strategy unifies the advantages of both macrocycle and framework in one system, achieving visualization, recyclability, and easy processability simultaneously. The present study paves an easy, efficient, and general platform for constructing dynamic optical materials

Successive Layer-by-Layer Strategy for Multi-Shell Epitaxial Growth: Shell Thickness and Doping Position Dependence in Upconverting Optical Properties

One pot successive layer-by-layer (SLBL) strategy is introduced to fabricate the core/shell upconversion nanoparticles (NPs) for the first time by using high boiling-point Re-OA (rare-earth chlorides dissolved in oleic acid at 140 °C) and Na-TFA-OA (sodium trifluoroacetate dissolved in oleic acid at room temperature) as shell precursor solutions. This protocol is flexible to deposit uniform multishell on both hexagonal (β) and cubic (α) phase cores by successive introducing of the shell precursor solutions. Shell thickness of the obtained NPs with narrow size distribution (σ < 10%) can be well controlled from 1 monolayer (∼0.36 nm) to more than 20 monolayers (∼8 nm) by simply tuning the amounts of the shell precursors. Furthermore, the tunable doping positions (core doping and shell doping) can also be achieved by adjusting the species and addition sequence of the shell precursors. As a result of the high quality uniform shell and advanced core/shell structures, the optical properties of the obtained core/shell NPs could be improved in upconversion luminescence efficiency (up to 0.51 ± 0.08%), stability (more resistant to quenching by water) and multicolor luminescence emission

Achieving <i>In Situ</i> Dynamic Fluorescence in the Solid State through Synergizing Cavities of Macrocycle and Channels of Framework

To achieve in situ dynamic fluorescence in the solid state and unveil the mechanism remain a formidable challenge. Herein, through synergizing the cavities of macrocycles for dynamic complexing and the channels of frameworks for facile transit, we construct intrinsic channels from an emissive cyclophane and realize precisely tunable emission in the solid state through the sequential guests’ exchange. Specifically, two design criteria involve (1) The twisted cyanostilbene units not only endow the systems with solid-state fluorescence but also tailor the π–π interactions in the complex to generate the desired emission and (2) the large cavity of cyclophane results in the formation of ternary complexes with controllable binding affinity which further assemble into robust channels for the guests’ exchange in the bulky state. This strategy unifies the advantages of both macrocycle and framework in one system, achieving visualization, recyclability, and easy processability simultaneously. The present study paves an easy, efficient, and general platform for constructing dynamic optical materials