Directly using natural materials as supporting material and reducing agent to obtain supported catalysts is significance along with the research of green and sustainable technologies. Herein, diatomite supported Pt (Pt/diatomite) catalysts were synthesized by the bioreduction method, through using Cinnamomum camphora (CC) leaf extract as reducing agent. As a result, the as-prepared 0.3% Pt/diatomite not only presented good benzene catalytic oxidation performance but also was catalytically stable and durable through long time on-stream, water vapor and carbon dioxide effect experiments. Through XPS, H2-TPR, H2-TPD, TEM, and in situ DRIFTS of CO adsorption analysis, it can be noticed that the high catalytic oxidation activity of 0.3% Pt/diatomite is attributed with more surface absorbed oxygen, good Pt dispersion and strong interactions between Pt and diatomite. Moreover, in situ DRIFTS of benzene oxidation experiments revealed that the hydrocarbon fragments were the intermediates during the process.

Herein, we report a novel type of smart graphene oxide nanocomposites (MGO@PNB) with excellent magnetism and high thermosensitive ion-recognition selectivity of lead ions (Pb 2+ ). The MGO@PNB are fabricated by immobilizing superparamagnetic Fe 3 O 4 nanoparticles (NPs) and poly( N -isopropylacrylamide- co -benzo-18-crown-6 acrylamide) thermosensitive microgels (PNB) onto graphene oxide (GO) nanosheets using a simple one-step solvothermal method and mussel-inspired polydopamine chemistry. The PNB are composed of cross-linked poly( N -isopropylacrylamide) (PNIPAM) chains with numerous appended 18-crown-6 units. The 18-crown-6 units serve as hosts that can selectively recognize and capture Pb 2+ from aqueous solution, and the PNIPAM chains act as a microenvironmental actuator for the inclusion constants of 18-crown-6/Pb 2+ host–guest complexes. The loaded Fe 3 O 4 NPs endow the MGO@PNB with convenient magnetic separability. The fabricated MGO@PNB demonstrate remarkably high ion-recognition selectivity of Pb 2+ among the coexisting metal ions because of the formation of stable 18-crown-6/Pb 2+ inclusion complexes. Most interestingly, the MGO@PNB show excellent thermosensitive adsorption ability toward Pb 2+ due to the incorporation of PNIPAM functional chains on the GO. Further thermodynamic studies indicate that the adsorption of Pb 2+ onto the MGO@PNB is a spontaneous and endothermic process. The adsorption kinetics and isotherm data can be well described by the pseudo-second-order kinetic model and the Langmuir isotherm model, respectively. Most importantly, the Pb 2+ -loaded MGO@PNB can be more easily regenerated by alternatively washing with hot/cold water than the commonly used regeneration methods. Such multifunctional graphene oxide nanocomposites could be used for specific recognition and removal of Pb 2+ from water environment.

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Although titanium silicalite-1 (TS-1) with enhanced Lewis acidity can show significant catalytic functionality, the effective and green synthesis of such a TS-1 zeolite still remains a challenge. In this work, a biophenol-mediated solvent-free strategy is adopted to synthesize bio-TS-1 with an improvement of acidity character. Systematic characterizations are devoted to inspect the structural and acidic properties of the as-prepared bio-TS-1. Furthermore, density functional theory simulations are carried out to reveal the underlying mechanism for such an improvement of acidity. It is found that biophenol serving as a mediating agent realizes a homogeneous crystallization process for bio-TS-1, which fundamentally favors titanium substitution of framework sites, especially those with unique acidity. This improvement of acidity boosts the intrinsic catalytic reactivity of Ti−OOH species, further increasing the performances toward propylene epoxidation. The presented strategy together with mechanistic results clarifies the relationship between the structure and acidity in TS-1 zeolite and brings forward a promising approach to develop better TS-1 zeolites by regulating the crystallization process.

A major challenge in oil/water separation is the processing of surfactant-stabilized emulsions from the water medium. One of the feasible schemes of emulsion separation is the porous melamine sponge coupled with functional particles. Here, we proposed a novel superhydrophobic metal−organic framework (MOF)-based sponge for water-in-oil emulsion separation. The porous melamine sponge was combined with poly(dimethylsiloxane) (PDMS)-coated hydrophobic SiO 2 and UiO66-OSiR particles were prepared for demulsification via the one-step dipping method for the first time. The PDMS@SiO 2 @ UiO66-OSiR sponge revealed excellent superhydrophobicity at a water contact angle of 160.7°and superlipophilicity at an oil contact angle of 0°. Compared with the pristine melamine sponge, the size-controllable PDMS@SiO 2 @UiO66-OSiR sponge could separate stabilized water-in-oil emulsions with ultrahigh separation efficiency (>98.64%) and high flux (e.g., 970 L•m −2 •h −1 ). Meanwhile, the PDMS@SiO 2 @UiO66-OSiR sponge exhibited superior durability and mechanical reusability. Under harsh conditions such as strong acid and alkali, organic solvent corrosion, etc., all water contact angles of the PDMS@SiO 2 @UiO66-OSiR sponge were over 152°. Furthermore, the stress decreased by 5% when the sponge was subjected to 10 loading/unloading compression cycles at a constant strain of 60%. These results demonstrate that the PDMS@SiO 2 @UiO66-OSiR sponge can efficiently separate water-in-oil emulsions through its adjustable porous structure coupled with demulsification and hydrophobic particles. This study provides a step forward in developing a feasible strategy for the MOFbased sponge for emulsion separation.