Search

Lanthanum-modified mesoporous graphite nitride carbon composites (La-g-C3N4) were synthesized using a thermal shrinkage polymerization method. The samples underwent characterization through X-ray diffraction (XRD), Fourier transform infrared (FT-IR) spectroscopy, scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), and Brunauer–Emmet–Teller (BET) analysis. The results revealed that the La30-g-C3N4 sample displayed a more porous layered morphology with a uniform pore structure. The BET surface area of the sample was found to be 38.6 m2 g−1, which is 5.8 times higher than that of the undoped sample g-C3N4. The sample exhibited a type IV isotherm, indicating its mesoporous nature with a pore size distribution ranging from 3 to 20 nm. The application of these materials was investigated for the degradation of tetracycline (TC) and acidic fuchsin (AF) in simulated wastewater. The results demonstrated that the La30-g-C3N4 sample exhibited rapid and efficient degradation, along with excellent adsorption capacity for both TC and AF. Within 5 minutes, the degradation efficiency of the La30-g-C3N4 sample for TC and AF was measured to be 83.1% and 74.1%, respectively, with corresponding adsorption capacities of 63.9 mg g−1 and 129.4 mg g−1. The kinetic and thermodynamic analysis of the adsorption process revealed that the adsorption of TC and AF by La30-g-C3N4 followed the quasi-second-order kinetics and Langmuir adsorption isotherm model, indicating a predominantly single-layer chemical adsorption process. Furthermore, the composite material exhibited good cycling stability and maintained excellent adsorption performance even after six repeated uses. [ABSTRACT FROM AUTHOR]

The electrocatalytic reduction of CO2 using electricity produced from renewable resources is a strategy for achieving CO2 emission reduction and sustainable energy development. Further, the reaction has a large number of industrial practical applications, since CO2 can be converted to fuels via downstream chemical processing of the CO product. Herein, we successfully synthesized a low Mn-content single-atom catalyst (SAC) with Mn–N2O2 sites, covalently integrated into carbon nanosheets (Mn–NO/CNs) using a one-pot synthesis method. The Mn–NO/CN catalyst displays efficient electrocatalytic performance for the CO2 reduction reaction (CO2RR). Using an H-type electrolytic cell, the maximum CO Faraday efficiency (FE) at −0.460 V (V vs. RHE) reaches 96.0% in 0.5 M KHCO3 electrolyte. In the flow cell measurements, Mn–NO/CNs exhibits a current density of 28 mA cm−2 at a very low potential of −0.425 V (V vs. RHE) for the CO2RR with 1.0 M KOH as the mobile phase. The FECO remains above 80% even after 70 h, demonstrating the excellent durability of the catalyst even at a very low potential. The X-ray absorption spectra (XAS) and DFT calculations show that the Mn–N2O2 site is the active catalytic center, which facilitates the adsorption of CO2 and significantly lowers the free energy barrier leading to the formation of the critical intermediate *COOH. The presence of dual N and O coordinated to the single atom metal sites embedded in the 2D carbon nanosheet significantly improves catalytic activity for the reduction of CO2. Therefore, the catalytic performance of the single atom metal catalyst can be enhanced by adjusting the coordination environment. [ABSTRACT FROM AUTHOR]

Specific targeted drug delivery and controllable release of drugs at tumor regions are two of the main challenges for hepatocellular carcinoma (HCC) therapy, particularly post metastasis. Herein, we present a platelet membrane-facilitated local chemo-photothermal therapy strategy, in which polypyrrole (PPy) nanoparticles act as photothermal agents and along with antitumor drug doxorubicin (DOX) are encapsulated into platelet membranes (PLT-PPy–DOX). The particles are endowed with immune evasiveness and tumor targeting abilities from platelet membranes, and are then intravenously injected into an orthotopic mouse model of HCC. As expected, the PLT-PPy–DOX nanoplatforms were abundant in the tumor tissues. Hyperthermia was generated under laser irradiation (808 nm) not only to ablate tumor cells directly but also to increase the triggered release of DOX. This combination of local chemotherapy and photothermal therapy demonstrated excellent antitumor efficiency in suppressing primary tumor growth and inhibiting tumor metastases. This localized therapy which adopts biocompatible natural cell membranes and good biodegradable organic photothermal agents may provide new insights into designing biomimetic nano-vehicles for personalized therapy of HCC. [ABSTRACT FROM AUTHOR]