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Abstract: Hollow carbon nanospheres were prepared via a rapid detonation technique, by using negative-oxygen balance explosive trinitrotoluene and nickel powder as starting materials and inorganic acid as solvent. The carbon/metal nanocomposite particles precursor with core–shell structure was engendered firstly during detonation, and then the metal nickel core was dissolved through inorganic acid to attain the hollow carbon nanospheres. High-Resolution Transmission Electron Microscope, X-ray diffraction and Raman spectrum were used to characterize the precursor and the as-synthesized samples respectively. The results show that the external diameter of the hollow carbon nanospheres is 25–150 nm and the thickness of the wall is about 2–10 nm. The surface of hollow carbon nanosphere displays multilayer wall in structure with 0.35 nm space between the layers. Based on the experimental results, possible formation mechanism was also proposed. [Copyright &y& Elsevier]

Textile‐based generators that can convert low‐grade energy from the human body or environment into sustainable electricity have generated immense scientific interest in self‐powered wearable applications. However, their low power density and environmental suitability have extremely restricted their portable applications in complex and mutable environments. Herein, an asymmetric sandwich structure between molybdenum disulfide (MoS2)‐carbonized silks (MCs) and MoS2/MXene–Cottons (MMCs) to construct efficient thermo–hydroelectric generators (THEGs) that synergistically harvest heat‐moisture energy to generate considerable electricity is rationally designed. Notably, the large surface area of MoS2/MXene van der Waals heterojunctions (vdWhs) enables efficient charge collection, and the vertical MoS2 nanosheet arrays supply abundant nanochannels for a highly efficient hydration effect, generating an output power density of 32.26 µW cm−2 after wetting with deionized water. Combined with the sensitive temperature recognition ability with a Seebeck coefficient of 23.5 µV K−1, the application possibilities of these prepared THEGs in the mutual conversion of fingertip temperature/language, and the monitoring of the human physiological state is foresee. [ABSTRACT FROM AUTHOR]

Precise fabrication of organic micro/nanostructures with regular morphology has gained a considerable concern in developing high‐performance optoelectronic devices, which is still a huge challenge to realize tunable morphology without the dependence on molecule packing arrangement. Herein, a thermodynamic/kinetic controlled self‐assembly for triphenylene‐7,7,8,8‐tetracyanoquinodimethane (TP‐TCNQ) cocrystal, with well‐defined microwires and microplates based on the same crystal structure, is proposed. With the low solution concentration of C = 5 mm, the comparable growth rates along [011] driven by π–π interaction and along [100] driven by charge‐transfer (CT) interaction facilitate the formation of thermodynamically favored shape of microplates. In contrast, the prominent CT interaction along [100] leads to the construction of microwires at kinetic state under high‐concentration solution of C = 10 mm. Furthermore, the prepared TP‐TCNQ microwires and microplates demonstrate isotropic photonic transmissions with the low optical loss coefficient of 0.033 and 0.042 dB µm−1, respectively. This strategy provides a novel avenue to finely construct the organic microcrystals with desired morphology for potential optoelectronics. [ABSTRACT FROM AUTHOR]

Optical interconnects exhibit superior potential in the precise regulation of photon transmission for organic photonic circuits. However, the rational design of well‐defined organic heterostructures toward active optoelectronics remains challenging. Herein, we designed organic branched heterostructures (OBHs) with accurate spatial organization for optical interconnection. Notably, the precise regulation of OBHs has been controllably achieved including the trunk morphologies and the branched microwire number. Significantly, these as‐prepared OBHs inherently exhibit the multichannel coupling outputs and the excitation position‐dependent waveguide characteristics, leading to various outcoupling signals with tunable intensity and emission colors. The optical interconnects are realized due to the occurrence of exciton conversion and photon propagation between branch and trunk at the heterojunction, benefiting the application possibilities of two‐dimensional (2D) optical barcodes. [ABSTRACT FROM AUTHOR]

Optical interconnects exhibit superior potential in the precise regulation of photon transmission for organic photonic circuits. However, the rational design of well‐defined organic heterostructures toward active optoelectronics remains challenging. Herein, we designed organic branched heterostructures (OBHs) with accurate spatial organization for optical interconnection. Notably, the precise regulation of OBHs has been controllably achieved including the trunk morphologies and the branched microwire number. Significantly, these as‐prepared OBHs inherently exhibit the multichannel coupling outputs and the excitation position‐dependent waveguide characteristics, leading to various outcoupling signals with tunable intensity and emission colors. The optical interconnects are realized due to the occurrence of exciton conversion and photon propagation between branch and trunk at the heterojunction, benefiting the application possibilities of two‐dimensional (2D) optical barcodes. [ABSTRACT FROM AUTHOR]

Abstract: The Cd TiO2 nanorods were synthesized by the vapor transport method of water molecules, and urea was used as the carbon and nitrogen source. The samples were characterized by X-ray diffraction and photoelectron spectroscopy analysis. The scanning electron microscope images showed that as-prepared TiO2 powders were nanorods, which were formed by the stacking of nanoparticles with a uniform size around 40nm. The degradation of methylene blue with the prepared nanorods demonstrated the photocatalytic activities of TiO2 under visible light are improved by doping with C and N elements. The main reasons were discussed: doping with C and N elements could enhance the corresponding visible-light absorption of TiO2. On the other hand, doping C and N could create more oxygen vacancies in the TiO2 crystals, which could capture the photogenerated electrons more effectively. Thus, more photogenerated holes could be left to improve the photocatalytic activity of TiO2. [Copyright &y& Elsevier]

The solar thermoelectric (STE) generator is constituted by a high-thermopower thermocell and a NIR selective Cs 0.32 WO 3 -based photothermal membrane, which can provide a significant all-weather thermoelectric generation. This work demonstrates a novel strategy for STE devices with high solar-thermoelectric conversion, durability, adaptability, and low-cost, which provide an alternative resolution in terms of a continuous power supply of wearable electronics. [Display omitted] • A wearable solar thermoelectric generator with all-weather power output is prepared. • Selective NIR absorption of Cs 0.32 WO 3 benefits colouring and photothermal conversion. • Heat concentration of photothermal membrane promotes enhanced temperature gradient. • This work delivers a resolution of continuous power supply for wearable electronics. Harvesting heat or solar energy to directly generate affordable and sustainable electricity holds great promise toward both fundamental science and practical applications in self-powered wearable electronics. However, solar thermoelectric (STE) devices remain challenging in establishing a stable and significant temperature gradient (Δ T) across thermoelectric materials for cost-effective electricity generation. Herein, a wearable STE generator with all-weather and high-performance electricity generation was elaborately designed and synthesized sandwiched by a thermogalvanic cell and a large-area nanofiber membrane of Cs 0.32 WO 3 (CWO) nanoparticles with strong near-infrared (NIR) absorption. These prepared CWO membranes, which were prepared via an electrostatic spinning technique, present a high photothermal conversion efficiency of 42.7 % with no degradation after running for 10 cycles. Notably, a significant Δ T of 31.5 K across the thermoelectric modular was achieved for STE generation via the thermal concentration of these photothermal membranes under natural sunlight. Owing to the high thermopower of 2.87 mV K−1 for each p-n pair, STE generation demonstrates a maximum output voltage of 200 mV under natural solar irradiance during the time period of noon. This work explores a new strategy to achieve efficient heat management of STE devices for high electricity generation under all-weather conditions, which demonstrates great potential for self-powered wearable electronics. [ABSTRACT FROM AUTHOR]

• Urchin-liked nanoparticles were prepared by microwave-induced hydrolysis process. • Urchin-liked nanoparticles made up of CuO/Cu(OH) 2 substructure nanowires. • Urchin-liked nanoparticles present the porous structure with BET of 230.67 m2/g. • Maximum adsorption capacity for Cr(Ⅵ) on Cu-based nanoparticles is 357.25 mg/g. • The Cr(VI) adsorption was an endothermic and spontaneous process. The hierarchical CuO/Cu(OH) 2 urchin-like nanoparticles with branching nanowires were rationally constructed under the ultrasonic hydrolysis treatment based on the Cu-based hollow spheres by microwave treatment. Moreover, due to the novel hierarchical nanostructure with a high specific surface area (230.67 m2/g) and a porous structure (the average pore volume was 0.96 cm3/g), hierarchical CuO/Cu(OH) 2 urchin-like nanoparticles demonstrated an outstanding adsorbent properties for Cr(VI). The maximal adsorption proportion was 95.4% at 100 mg/L initial Cr(VI) concentrations, the maximum adsorption capacity at 298 K and pH 4.0 was 425.49 mg/g. [Display omitted] Hierarchical self-assembly nanomaterials with high spatial/angular precision have attracted intensive attention in the urgent research focus in industrial and environmental fields, such as the efficient removal of heavy metal ions from aqueous solution. Herein, we developed an facile microwave-induced ultrasonic hydrolysis approach for the fine synthesis of the hierarchical CuO/Cu(OH) 2 urchin-like nanoparticles, which is comprised by Cu-based substructure nanowires with an average diameter of ~5 nm. Benefiting from the high specific surface area of 230.67 m2/g, the urchin-like CuO/Cu(OH) 2 hierarchical nanoparticles demonstrated a high maximum adsorption capacity of 357.25 mg/g at pH = 6.0 and T = 298 K for Cr(VI). Furthermore, the corresponding removed approximately 95% can be achieved after the adsorption process for 30 min, suggesting the fast adsorption for Cr(VI). Thermodynamic and kinetic investigations revealed that the Cr(VI) adsorption on the urchin-like CuO/Cu(OH) 2 hierarchical nanoparticles was an endothermic and spontaneous process, which could be well fitted by the pseudo-second-order kinetic model. This approach provides new prospects for curbing heavy metal pollution in the environment based on the hierarchical self-assembly nanomaterials. [ABSTRACT FROM AUTHOR]

Abstract: AgI doped SnO2 nano-composites were prepared by the chemical coprecipitation method and were characterized by the X-ray diffraction, transmission electron microscopy and X-ray photoelectron spectroscopy. Results showed that main of the I− ions remained in the AgI lattice which is highly dispersed in the system. The photo-catalytic experiments performed under visible light irradiation using methylene blue as the pollutant revealed that not only the photo-catalytic activity but also the stability of SnO2 based photocatalyst could be improved by introduction of an appropriate amount of AgI, and the result was further supported by the UV–Vis diffuse reflection spectra and the electron spin-resonance spectra. Among all of the samples, AgI–SnO2 nano-composite with 2At% AgI exhibited the best catalytic efficiency and stability. [Copyright &y& Elsevier]