Currently, the production of solar fuels by the photoreduction of CO 2 with H 2 O is limited by the slow reaction rate and low efficiency of solar energy conversion. Combining concentrated solar power and plasmonic nanomaterials is a promising strategy to enhance photothermal transformation and promote solarto-fuel conversion. Herein, a nanocatalyst comprising gold anchored on TiO 2 was fabricated using a regular deposition-precipitation method. The nanocatalyst showed improved performance in CO 2 reduction with H 2 O under concentrated full-spectrum irradiation owing to the coupling of photo-and thermal energies. Macroscopic experiments demonstrated a clear correlation between the light intensity and the syngas yield, and a CO 2 conversion rate of 6.35% was achieved after 3 h under simulated sunlight illumination of 1644 mW/cm 2 . Photoelectrochemical measurements and finite element method simulations indicated that Au/TiO 2 achieved better separation and transport of the photoexcited carriers than TiO 2 owing to localized surface plasmon resonance that heats the nanocatalysts under concentrated full-spectrum irradiation. In situ diffuse reflectance infrared Fourier transform spectroscopy analysis also suggested that the photothermal effect accelerates the formation of intermediates such as formate and acetate and therefore enhances the overall photocatalytic rate. These results highlight the excellent potential of combining concentrated solar power and plasmonic nanostructures to realize the synergistic utilization of photon energy and thermal energy. Such a combination not only promotes the solar-to-fuel conversion efficiency but also paves the way for future applications in large-scale scenarios.

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The amine (NH2)-functionalized UiO-66 was successfully anchored on disorderly layered clinoptilolite (CP) via surfactant (poly(ethylene glycol) (PEG) and poly(vinylpyrrolidone) (PVP))-assisted induction. The structural features and physicochemical parameters of the resultant UiO-66-on-CPs were characterized by powder X-ray diffraction (XRD) patterns, scanning/transmission electron microscopy (SEM/TEM) images, Fourier transform infrared (FT-IR) spectra, N2 sorption isotherms, and small-angle X-ray scattering (SAXS) patterns. The results demonstrated that the growth of UiO-66-NH2 nanoparticles facilitated the disorder degree of the crystal plane of CP along the a-axis, while the addition of PEG in the hydrothermal synthesis system of CP was conducive to the formation of a flower-like microstructure and the introduction of PVP was beneficial to the nucleation and growth of UiO-66-NH2 nanoparticles with a small size (40 nm) on the surfaces of the obtained CP-PEG lamellas. Finally, the gas-selective adsorption and separation performances of CO2 and CH4 were evaluated using the synthesized disorderly layered UiO-66-on-CP heterostructures as adsorbents, indicating that the NH2-functionalized UiO-66-on-CP exhibited a superior selective factor (3.66) of CO2/CH4. These results elucidated that the proposed approach is a promising strategy for constructing MOF-on-zeolite heterostructures, which may open an avenue to expand CP application and improve their performance.

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The pH-responsive fluorescent P(1,8-naphthalic anhydride (NA)-acrylic acid (AA)) matrix was successfully prepared by a doping method using poly(acrylic acid) (PAA) as a pH-sensitive polymer and NA as a fluorescent tracer. The fluorescent behaviors of the used NA dispersed in PAA frameworks were demonstrated based on fractal features combined with various characterizations, such as small-angle X-ray scattering (SAXS) patterns, photoluminescence (PL) spectra, scanning electron microscope (SEM) images, thermogravimetry (TG) profiles, Fourier transform infrared (FT-IR) spectroscopy, and time-resolved decays. The effects of NA-doping on the representative fluorescent P(NA-AA) were investigated, in which the fluorescent performance of the doped NA was emphasized. The results indicated that aggregated clusters of the doped NA were gradually serious with an increase in NA doping amount or extension of NA doping time, accompanied by an increase in mass fractal dimension (Dm) values. Meanwhile, the doped NA presented stable fluorescent properties during the swelling–shrinking process of PAA. Ibuprofen (IBU) was used as a model drug, and fractal evolutions of the obtained P(NA-AA) along with the drug loading and releasing behaviors were evaluated via SAXS patterns, in which the drug-loaded P(NA-AA) presented surface fractal (Ds) characteristics, while the Dm value varied from 2.94 to 2.58 during sustained drug-release in pH 2.0, indicating occurrences of its structural transformation from dense to loose with extension of IBU-releasing time. Finally, the cytotoxicity and cellular uptake behaviors of the obtained P(NA-AA) were preliminarily explored. These demonstrations revealed that the resultant P(NA-AA) should be a potential intelligent-responsive drug carrier for targeted delivery.

Fe(III)-modified clinoptilolites (Fe-CPs) were prepared by hydrothermal treatment. The collapse of the heulandite skeletons was avoided by adjusting the pH value using HCl solution, showing the maximum relative crystallinity of the Fe-CPs at an optimal pH of 1.3. The competitive exchange performances between Fe3+ ions and H+ with Na+ (and K+) suggested that the exchange sites were more easily occupied by H+. Various characterizations verified that the hydrothermal treatments had a strong influence on the dispersion and morphology of the isolated and clustered Fe species. The high catalytic activity of the oxygen evolution reaction indicated the insertion of Fe3+ into the skeletons and the occurrences of isomorphic substitution. The fractal evolutions revealed that hydrothermal treatments with the increase of Fe content strongly affected the morphologies of Fe species with rough and disordered surfaces. Meanwhile, the Fe(III)-modified performances of the CPs were systematically investigated, showing that the maximum Fe-exchange capacity was up to 10.6 mg/g. Their thermodynamic parameters and kinetic performances suggested that the Fe(III)-modified procedures belonged to spontaneous, endothermic, and entropy-increasing behaviors. Finally, their adsorption capacities of CO2 at 273 and 298 K were preliminarily evaluated, showing high CO2 adsorption capacity (up to 1.67 mmol/g at 273 K).

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The random lamellae of the synthetic CP were synthesized with a hydrothermal approach using o-Phenylenediamine (OPD) as a modifier. The decreases in the order degree of the CP synthesized in the presence of the OPD resulted from the loss of long-range order in a certain direction. Subsequently, the ultrasonic treatment and washing were conducive to further facilitate the disordered arrangements of its lamellae. The possible promotion mechanism regarding the nucleation and growth behaviors of the sol-gel particles was proposed. The fractal evolutions of the aluminosilicate species with crystallization time implied that the aluminosilicate species became gradually smooth to rough during the crystallization procedures since the amorphous structures transformed into flower-like morphologies. Their gas adsorption and separation performances indicated that the adsorption capacity of CO2 at 273 K reached up to 2.14 mmol·g−1 at 1 bar, and the selective factor (CO2/CH4) up to 3.4, much higher than that of the CPs synthesized without additive OPD. The breakthrough experiments displayed a longer breakthrough time and enhancement of CO2 uptake, showing better performance for CO2/CH4 separation. The cycling test further highlighted their efficiency for CO2/CH4 separation.