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N-rich organic materials bearing polyphenolic moieties in their building networks and nanoscale porosities are very demanding in the context of designing efficient biomaterials or drug carriers for the cancer treatment. Here, we report the synthesis of a new triazine-based secondary-amine- and imine-linked polyphenolic porous organic polymer material TrzTFPPOP and explored its potential for in vitro anticancer activity on the human colorectal carcinoma (HCT 116) cell line. This functionalized (-OH, -NH-, -C=N-) organic material displayed an exceptionally high BET surface area of 2140 m2 g−1 along with hierarchical porosity (micropores and mesopores), and it induced apoptotic changes leading to high efficiency in colon cancer cell destruction via p53-regulated DNA damage pathway. The IC30, IC50, and IC70 values obtained from the MTT assay are 1.24, 3.25, and 5.25 μg/mL, respectively.

In this study, high specific surface area ZnO nanoparticles (> 30 m 2 /g) were synthesized via the controlled aqueous carbonation of zinc ions using CO 2 gas, leading to the formation of hydrozincite (basic zinc hydroxycarbonate) as a precursor, followed by mild-temperature calcination and thermal decomposition. The response surface methodology (RSM) was utilized to statistically evaluate and optimize the effects of key process parameters, i.e. synthesis temperature, carbonation time, initial pH and liquid-to-solid ratio. The BET surface area analysis revealed that the synthesized ZnO nanoparticles possessed a high specific surface area with a porous structure consisting of both macropores and mesopores. The developed statistical model successfully predicted the optimum synthesis conditions (i.e. a synthesis temperature of 70 °C, a carbonation time of 1 h, an initial pH of 9 and a liquid-to-solid ratio of 20 mL/g) and its validity was confirmed by the strong agreement between predicted and experimental values (31.3 m 2 /g and 29.1 m 2 /g, respectively) with a relative error of 7%. The findings of this study demonstrated how statistical optimization could be employed to reproducibly tune the surface and textural properties of ZnO prepared via the carbonation-calcination route. The resulting high SSA ZnO nanoparticles show promise for surface-driven applications such as adsorption and heterogeneous catalysis.

Single-atom catalysts 1 make exceptionally efficient use of expensive noble metals and can bring out unique properties 1 – 3 . However, applications are usually compromised by limited catalyst stability, which is due to sintering 3 , 4 . Although sintering can be suppressed by anchoring the metal atoms to oxide supports 1 , 5 , 6 , strong metal–oxygen interactions often leave too few metal sites available for reactant binding and catalysis 6 , 7 , and when exposed to reducing conditions at sufficiently high temperatures, even oxide-anchored single-atom catalysts eventually sinter 4 , 8 , 9 . Here we show that the beneficial effects of anchoring can be enhanced by confining the atomically dispersed metal atoms on oxide nanoclusters or ‘nanoglues’, which themselves are dispersed and immobilized on a robust, high-surface-area support. We demonstrate the strategy by grafting isolated and defective CeO x nanoglue islands onto high-surface-area SiO 2 ; the nanoglue islands then each host on average one Pt atom. We find that the Pt atoms remain dispersed under both oxidizing and reducing environments at high temperatures, and that the activated catalyst exhibits markedly increased activity for CO oxidation. We attribute the improved stability under reducing conditions to the support structure and the much stronger affinity of Pt atoms for CeO x than for SiO 2 , which ensures the Pt atoms can move but remain confined to their respective nanoglue islands. The strategy of using functional nanoglues to confine atomically dispersed metals and simultaneously enhance their reactivity is general, and we anticipate that it will take single-atom catalysts a step closer to practical applications. Nanometre-sized ‘nanoglue’ islands of CeO x on high-surface-area SiO 2 are shown to suppress sintering and confine on average one Pt atom per island, leading to stable single-atom catalysts under oxidizing and reducing environments.

Single metal-organic frameworks (MOFs), constructed from the coordination between one-fold metal ions and organic linkers, show limited functionalities when used as precursors for nanoporous carbon materials. Herein, we propose to merge the advantages of zinc and cobalt metals ions into one single MOF crystal ( i.e. , bimetallic MOFs). The organic linkers that coordinate with cobalt ions tend to yield graphitic carbons after carbonization, unlike those bridging with zinc ions, due to the controlled catalytic graphitization by the cobalt nanoparticles. In this work, we demonstrate a feasible method to achieve nanoporous carbon materials with tailored properties, including specific surface area, pore size distribution, degree of graphitization and content of heteroatoms. The bimetallic-MOF-derived nanoporous carbon are systematically characterized, highlighting the importance of precisely controlling the properties of the carbon materials. This can be done by finely tuning the components in the bimetallic MOF precursors and thus designing optimal carbon materials for specific applications.

A TiO 2 heterostructure modified with carbon nitride nanosheets (CN-NSs) has been synthesized via a direct interfacial assembly strategy. The CN-NSs, which have a unique two-dimensional structure, were favorable for supporting TiO 2 nanoparticles (NPs). The uniform dispersion of TiO 2 NPs on the surface of the CN-NSs creates sufficient interfacial contact at their nanojunctions, as was confirmed by electron microscopy analyses. In comparison with other reported metal oxide/CN composites, the strong interactions of the ultrathin CN-NSs layers with the TiO 2 nanoparticles restrain their re-stacking, which results in a large specific surface area of 234.0 m 2 ·g –1 . The results indicate that the optimized TiO 2 /CN-NSs hybrid exhibits remarkably enhanced photocatalytic efficiency for dye degradation (with k of 0.167 min –1 under full spectrum) and H 2 production (with apparent quantum yield = 38.4% for λ = 400 ± 15 nm monochromatic light). This can be ascribed to the improved surface area and quantum efficiency of the hybrid, with a controlled ratio that reaches the appropriate balance between producing sufficient nanojunctions and absorbing enough photons. Furthermore, based on the identification of the main active species for photodegradation, and the confirmation of active sites for H 2 evolution, the charge transfer pathway across the TiO 2 /CN-NSs interface under simulated solar light is proposed.

A high surface area ZnO support (HSA-ZnO) has been fabricated in a unique thermal decomposition process using broken rice grains as a sacrificial template, zinc acetate trihydrate as ZnO precursor. As-prepared ZnO support exhibited a surface area of 145 m 2 /gm, which is six times higher than the commercial ZnO. Further, copper-supported HSA-ZnO catalysts with different copper loadings (4, 8, 12 and 16 wt%) were prepared by using wet impregnation method and characterized by physicochemical techniques such as X-ray diffraction (XRD), Thermal gravimetric analysis(TGA), BET surface area, CO 2 temperature programmed desorption of (CO 2 -TPD), temperature programmed reduction(TPR) and N 2 O pulse chemisorption measurements. The catalytic activity of all the prepared catalysts were tested in dehydrogenation of cyclohexanol in a continuous flow reactor. A variety of reaction factors were examined, including the impact of temperature, the influence of copper loadings, and the catalysts stability. Lab-made HSA ZnO presented better properties than the commercial and the one without sacrificial template preparation. Among all the catalysts, 12 wt% Cu/HSA-ZnO catalyst exhibited the highest conversion (75%) and cyclohexanone selectivity (89%). The high activity and stability of optimal 12 wt% Cu-loaded catalysts are due to highly dispersed copper particles, better reducibility, and the strong interactions between the Cu particles and rice-derived ZnO support.

In this work, Zn-Co@BTC was synthesized under environmentally friendly, economical, and green conditions. It was prepared by the solvothermal method using zinc nitrate hexahydrate and cobalt nitrate hexahydrate as the metals, with benzene-1,3,5-tricarboxylate (BTC) as the ligand. The formation of Zn-Co@BTC MOF was confirmed by Ultraviolet–Visible spectroscopy (UV–Vis), X-ray diffraction, Fourier transform infrared, thermogravimetric analysis, Raman spectroscopy, X-ray Photoelectron Spectroscopy, Brunauer–Emmett–Teller surface area analysis, scanning electron microscopy, and Transmission electron microscopy. It exhibited high thermal stability, a large surface area, and strong antibacterial activity. The antibacterial activity was evaluated against the Bacillus cereus strain identified by 16S rRNA gene sequencing using optical density measurements and the cut plug method. The results showed remarkable antibacterial activity, achieving near-complete bacterial growth inhibition (99.9%) at 600 mg/L and complete inhibition (100%) at a concentration of 800 mg/L. These findings support the potential use of Zn-Co@BTC MOF as an antibacterial agent in biomedical applications.

Mesoporous silica nanostructures (MSNs) attract high interest due to their unique and tunable physical chemical features, including high specific surface area and large pore volume, that hold a great potential in a variety of fields, i.e., adsorption, catalysis, and biomedicine. An essential feature for biomedical application of MSNs is limiting MSN size in the sub-micrometer regime to control uptake and cell viability. However, careful size tuning in such a regime remains still challenging. We aim to tackling this issue by developing two synthetic procedures for MSN size modulation, performed in homogenous aqueous/ethanol solution or two-phase aqueous/ethyl acetate system. Both approaches make use of tetraethyl orthosilicate as precursor, in the presence of cetyltrimethylammonium bromide, as structure-directing agent, and NaOH, as base-catalyst. NaOH catalyzed syntheses usually require high temperature (>80 °C) and large reaction medium volume to trigger MSN formation and limit aggregation. Here, a successful modulation of MSNs size from 40 up to 150 nm is demonstrated to be achieved by purposely balancing synthesis conditions, being able, in addition, to keep reaction temperature not higher than 50 °C (30 °C and 50 °C, respectively) and reaction mixture volume low. Through a comprehensive and in-depth systematic morphological and structural investigation, the mechanism and kinetics that sustain the control of MSNs size in such low dimensional regime are defined, highlighting that modulation of size and pores of the structures are mainly mediated by base concentration, reaction time and temperature and ageing, for the homogenous phase approach, and by temperature for the two-phase synthesis. Finally, an in vitro study is performed on bEnd.3 cells to investigate on the cytotoxicity of the MNSs.

Spent activated carbon (SAC) usually exhibits a low specific surface area due to its high ash contents. In this study, pre-treatments, such as heat and acid treatments, were optimized to improve this feature. The heat pre-treatment did not reduce the ash content, nor did it increase the surface area. Because metallic ions adsorbed in SACs turn into ash upon the heat treatment. In the acid pre-treatment, the volatiles and fixed carbon were increased with decreasing ash contents. In this study, it was found that the surface area increase was correlated with the ratio between fixed carbon and ash. Among the pre-treatment methods, the combined heat and acid pre-treatment method highly increased the ratio, and therefore led to the surface area increase. Additionally, the acid pre-treatment was carried out using different types of acid (organic and inorganic acids) solutions to further improve the surface areas. The organic acid treatment caused a significant structural collapse compared to the inorganic acid treatment, decreasing the surface area. In particular, H3PO4 effectively removed ashes adsorbed on the activated carbon surface and regenerated the exhausted activated carbon. Both the heat and acid pre-treatments before chemical activation resulted in the positive effects such as strong desorption of pollutants and ashes within the internal structure of the activated carbon. Therefore, the regeneration introduced in this study is methodically the best method to regenerate SAC and maintain a stable structure.

Hybrid silica aerogels are promising materials for thermal insulation applications. Highly porous aerogels were synthesized from bridged bis(triethoxysilyl)methane BTEM and triethoxysilane TREOS silicon alkoxides via the sol‒gel process. The carbon content in the hybrid aerogels decreased with increasing amounts of TREOS. Crack-free monolith aerogels were synthesized through supercritical drying, which is crucial for thermal and optical investigations. The aerogels are characterized by high BET surface areas ranging from 700 to 1400 m²/g, pore volumes between 2.0 and 10.5 cm³/g, and a maximum porosity of 95%. The thermal conductivity of the aerogels at room temperature was measured via a hot disk apparatus. The materials exhibited ultralow thermal conductivity, reaching a minimum value of 15 mW/mK. This value ranks among the lowest reported values for silica-based aerogels in the literature. Optical transmittance measurements indicated high transparency, exceeding 80% in the visible region. Therefore, these exceptional properties of low density, high optical transparency, and low thermal conductivity make these materials promising candidates for transparent insulation applications. Graphical Abstract Highlights Highly porous hybrid aerogels were synthesized via the sol-gel process and supercritical CO 2 drying. The bulk density, shrinkage, and pore volume of the aerogels are influenced by the amount of TREOS. The BT2 aerogel achieved a minimum thermal conductivity of 15 mW/mK with a bulk density of 0.17 g/cm 3 The BT2 aerogel demonstrated 80% transmittance at a wavelength of 550 nm.