Effects of CaO and CaCO₃ on Heavy Metal Capture in Bottom Ash during Municipal Solid Waste Combustion under a CO₂/O₂ Atmosphere

Experiments were conducted to investigate the influence of CaO and CaCO₃ on the capture efficiency of heavy metals during the combustion of municipal solid waste (MSW) in CO₂/O₂ and N₂/O₂ atmospheres. Six heavy metal elements were studied in this paper, including Pb, Cd, Cu, Cr, Ni, and Zn. On the basis of the results, the operating temperature has a great effect on the transformation of Pb and Cd, while the amount of Cu, Cr, and Ni in the bottom ash are affected only slightly by changes in the temperature and atmosphere. The volatilization of Cd, Cu, Cr, and Zn marginally decreased with the addition of CaCO₃ or in a CO₂/O₂ atmosphere (oxy-fuel combustion). The X-ray diffraction results show that CaO and CaCO₃ have the same ability to capture heavy metals under CO₂/O₂ and N₂/O₂ atmospheres as a result of the reaction of CaO with CO₂. Thermodynamic equilibrium calculations indicate that CaO or CaCO₃ could barely hinder the volatilization of heavy metals by chemical reactions with the heavy metals but might hinder their volatilization by their physical adsorption. The initial forms of the heavy metals in the MSW may be another factor that affects the volatilization of the heavy metals. The importance of these forms is indicated by these six heavy metals having similar enrichment behaviors in both the CO₂/O₂ and N₂/O₂ atmospheres with CaO or CaCO₃ additives; the calculations predict that these heavy metals have the same main species, except for a slight change in the content of these species

Janus Silver/Silica Nanoplatforms for Light-Activated Liver Cancer Chemo/Photothermal Therapy

Stimuli-triggered nanoplatforms have become attractive candidates for combined strategies for advanced liver cancer treatment. In this study, we designed a light-responsive nanoplatform with folic acid-targeting properties to surmount the poor aqueous stability and photostability of indocyanine green (ICG). In this Janus nanostructure, ICG was released on-demand from mesoporous silica compartments in response to near-infrared (NIR) irradiation, exhibiting predominant properties to convert light to heat in the cytoplasm to kill liver cancer cells. Importantly, the silver ions released from the silver compartment that were triggered by light could induce efficient chemotherapy to supplement photothermal therapy. Under NIR irradiation, ICG-loaded Janus nanoplatforms exhibited synergistic therapeutic capabilities both in vitro and in vivo compared with free ICG and ICG-loaded mesoporous silica nanoparticles themselves. Hence, our Janus nanoplatform could integrate ICG-based photothermal therapy and silver ion-based chemotherapy in a cascade manner, which might provide an efficient and safe strategy for combined liver cancer therapy

MIL-125-NH₂@TiO₂ Core–Shell Particles Produced by a Post-Solvothermal Route for High-Performance Photocatalytic H₂ Production

Metal–organic frameworks (MOFs) have proven to be an interesting class of sacrificial precursors of functional inorganic materials for catalysis, energy storage, and conversion applications. However, the controlled synthesis of MOF-derived materials with desirable compositions, structures, and properties still remains a big challenge. Herein, we propose a post-solvothermal route for the outer-to-inner loss of organic linkers from MOF, which is simple, rapid, and controllable and can be operated at temperature much lower than that of the commonly adopted pyrolysis method. By such a strategy, the MIL-125-NH₂ particles coated by TiO₂ nanosheets were produced, and the thickness of TiO₂ shell can be easily tuned. The MIL-125-NH₂@TiO₂ core–shell particles combine the advantages of highly active TiO₂ nanosheets, MIL-125-NH₂ photosensitizer, plenty of linker defects and oxygen vacancies, and mesoporous structure, which allows them to be utilized as photocatalysts for the visible-light-driven hydrogen production reaction. It is remarkable that the hydrogen evolution rate by MIL-125-NH₂@TiO₂ can be enhanced 70 times compared with the pristine MIL-125-NH₂. Such a route can be easily applied to the synthesis of different kinds of MOF-derived functional materials

Photocatalytic CO₂ Transformation to CH₄ by Ag/Pd Bimetals Supported on N‑Doped TiO₂ Nanosheet

To develop photocatalysts with desirable compositions and structures for improving the efficiency and selectivity of CO₂ conversion to CH₄ under mild conditions is of great importance. Here, we design an effective photocatalyst of bimetal (Ag/Pd) nanoalloys supported on nitrogen-doped TiO₂ nanosheet for CO₂ conversion. Such a novel photocatalyst combines multiple advantages of abundant Ti³⁺ ions, oxygen vacancies, and substitutional nitrogen that are favorable for catalyzing CO₂ reduction. It was found that CO₂ could be efficiently transformed to CH₄ under mild conditions, i.e., in aqueous solution and at atmospheric pressure and room temperature. The maximum production rate of CH₄ can reach 79.0 μmol g^–1 h^–1. Moreover, the Ag/Pd bimetals supported on N-doped TiO₂ nanosheet exhibit high selectivity to CH₄. The as-synthesized photocatalyst can be well recycled for CO₂ reduction

Janus Silver-Mesoporous Silica Nanocarriers for SERS Traceable and pH-Sensitive Drug Delivery in Cancer Therapy

A facile and cheap strategy was used to fabricate the novel Janus silver-mesoporous silica nanoparticles with excellent SPR and mesoporous properties for simultaneous SERS imaging and pH-responsive drug release, leading to the efficient cancer theranostic with less toxic effects

Janus Gold Nanoplatform for Synergetic Chemoradiotherapy and Computed Tomography Imaging of Hepatocellular Carcinoma

There is a pressing need to develop nanoplatforms that integrate multimodal therapeutics to improve treatment responses and prolong the survival of patients with unresectable hepatocellular carcinoma (HCC). Mesoporous silica-coated gold nanomaterials have emerged as a novel multifunctional platform combining tunable surface plasmon resonance and mesoporous properties that exhibit multimodality properties in cancer theranostics. However, their reduced radiation-absorption efficiency and limited surface area hinder their further radiochemotherapeutic applications. To address these issues, we designed Janus-structured gold-mesoporous silica nanoparticles using a modified sol–gel method. This multifunctional theranostic nanoplatform was subsequently modified <i>via</i> the conjugation of folic acid for enhanced HCC targeting and internalization. The loaded anticancer agent doxorubicin can be released from the mesopores in a pH-responsive manner, facilitating selective and safe chemotherapy. Additionally, the combination of chemotherapy and radiotherapy induced synergistic anticancer effects <i>in vitro</i> and exhibited remarkable inhibition of tumor growth <i>in vivo</i> along with significantly reduced systematic toxicity. Additionally, the Janus NPs acted as targeted computed tomography (CT)-imaging agents for HCC diagnosis. Given their better performance in chemoradiotherapy and CT imaging as compared with that of their core–shell counterparts, this new nanoplatform designed with dual functionalities provides a promising strategy for unresectable HCC theranostics

Metal–Organic Framework-Stabilized CO₂/Water Interfacial Route for Photocatalytic CO₂ Conversion

Here, we propose a CO₂/water interfacial route for photocatalytic CO₂ conversion by utilizing a metal–organic framework (MOF) as both an emulsifier and a catalyst. The CO₂ reduction occurring at the CO₂/water interface produces formate with remarkably enhanced efficiency as compared with that in conventional solvent. The route is efficient, facile, adjustable, and environmentally benign, which is applicable for the CO₂ transformation photocatalyzed by different kinds of MOFs

Superelastic, Highly Conductive, Superhydrophobic, and Powerful Electromagnetic Shielding Hybrid Aerogels Built from Orthogonal Graphene and Boron Nitride Nanoribbons

Three-dimensional (3D) elastic aerogels enable diverse applications but are usually restricted by their low thermal and electrical transfer efficiency. Here, we demonstrate a strategy for fabricating the highly thermally and electrically conductive aerogels using hybrid carbon/ceramic structural units made of hexagonal boron nitride nanoribbons (BNNRs) with in situ-grown orthogonally structured graphene (OSG). High-aspect-ratio BNNRs are first interconnected into a 3D elastic and thermally conductive skeleton, in which the horizontal graphene layers of OSG provide additional hyperchannels for electron and phonon conduction, and the vertical graphene sheets of OSG greatly improve surface roughness and charge polarization ability of the entire skeleton. The resulting OSG/BNNR hybrid aerogel exhibits very high thermal and electrical conductivity (up to 7.84 W m–1 K–1 and 340 S m–1, respectively) at a low density of 45.8 mg cm–3, which should prove to be vastly advantageous as compared to the reported carbonic and/or ceramic aerogels. Moreover, the hybrid aerogel possesses integrated properties of wide temperature-invariant superelasticity (from −196 to 600 °C), low-voltage-driven Joule heating (up to 42–134 °C at 1–4 V), strong hydrophobicity (contact angel of up to 156.1°), and powerful broadband electromagnetic interference (EMI) shielding effectiveness (reaching 70.9 dB at 2 mm thickness), all of which can maintain very well under repeated mechanical deformations and long-term immersion in strong acid or alkali solution. Using these extraordinary comprehensive properties, we prove the great potential of OSG/BNNR hybrid aerogel in wearable electronics for regulating body temperature, proofing water and pollution, removing ice, and protecting human health against EMI

Real-Time Visualizing and Tracing of HSV-TK/GCV Suicide Gene Therapy by Near-Infrared Fluorescent Quantum Dots

Exploring intracellular behavior of suicide gene is significant for improving the efficacy and safety of herpes simplex virus thymidine kinase gene/ganciclovir (HSV-TK/GCV) system in cancer therapy. Molecular imaging represents a powerful tool to understand gene transportation and function dynamics. In this work, we reported a quantum-dot-based technique for revealing the procedure of HSV-TK/GCV suicide gene therapy by constructing covalent linkage between near-infrared fluorescent quantum dots (QDs) and TK gene. This stable QD labeling did not influence either the QDs fluorescence or the biological activity of TK gene. Furthermore, we visualized and dynamically traced the intracellular behavior antitumor effect of TK gene in vitro and in vivo. It is demonstrated that TK gene was shuttled to the nucleus after a-24 h treatment; at that time the single dose of GCV administration exerts the gradually increasing lethal effect until to 72 h. Real-time tracing the formation of hepatocellular carcinoma treated with HSV-TK/GCV suicide gene system in vivo by QD-based NIR fluorescence imaging provides useful insight toward QD-based theranostics in future cancer therapy

Shape Engineering Boosts Magnetic Mesoporous Silica Nanoparticle-Based Isolation and Detection of Circulating Tumor Cells

Magnetic mesoporous silica nanoparticles (M-MSNs) are attractive candidates for the immunomagnetic isolation and detection of circulating tumor cells (CTCs). Understanding of the interactions between the effects of the shape of M-MSNs and CTCs is crucial to maximize the binding capacity and capture efficiency as well as to facilitate the sensitivity and efficiency of detection. In this work, fluorescent M-MSNs were rationally designed with sphere and rod morphologies while retaining their robust fluorescence and uniform surface functionality. After conjugation with the antibody of epithelial cell adhesion molecule (EpCAM), both of the differently shaped M-MSNs-EpCAM obtained achieved efficient enrichment of CTCs and fluorescent-based detection. Importantly, rodlike M-MSNs exhibited faster immunomagnetic isolation as well as better performance in the isolation and detection of CTCs in spiked cells and real clinical blood samples than those of their spherelike counterparts. Our results showed that shape engineering contributes positively toward immunomagnetic isolation, which might open new avenues to the rational design of magnetic-fluorescent nanoprobes for the sensitive and efficient isolation and detection of CTCs