Shuang Wang

Two pairs of chiral MOFs, DCF-15/LCF-15 and DCF-16/LCF-16, were constructed through assembly of achiral aggregation-induced emission (AIE)-type multidentate linkers (TPPE and TPA) and chiral camphoric acid (d/l-cam), exhibiting non-reciprocal CPL.

Ammonium nickel fluoride (NH₄NiF₃) undergoes progressive reconstruction via anodic oxidation in alkaline media and ultimately transforms into a F-doped NiOOH with excellent OER activity and durability.

Core–shell catalysts with functional shells can increase the activity and stability of the catalysts in selective catalytic reduction of NO_x with ammonia_x. However, the conventional approaches based on multistep fabrication for core–shell structures encounter persistent restrictions regarding strict synthesis conditions and limited design flexibility. Herein, a facile coaxial 3D printing strategy is for the first time developed to construct zeolite‐based core–shell monolithic catalysts with interconnected honeycomb structures, in which the hydrophilic noncompact silica serves as shell and Cu‐SSZ‐13 zeolite acts as core. Compared to a Cu‐SSZ‐13 monolith which suffers from the interfacial diffusion, the SiO₂ shell layer can increase the accessibility of active sites over Cu‐SSZ‐13@SiO₂, resulting in a 10–20% higher NO conversion at200−550 °C under 300 000 cm³ g⁻¹ h⁻¹. Meanwhile, a thicker SiO₂ shell enhances the hydrothermal stability of the aged catalyst by inhibiting the dealumination and the formation of CuO_x. Other representative monolithic catalysts with different topological zeolites as shell and diverse metal oxides as the core can be also realized by this coaxial 3D printing. This strategy allows multiple porous materials to be directly integrated, which allows for flexible design and fabrication of various core–shell monolithic catalysts with customized functionalities.

The metastable NiSeO3 center dot 2H(2)O canbe reconstructed into SeO3 (2-)-decoratedpolycrystalline NiO nanosheets during the alkaline HER process. Andthe surface-adsorbed SeO3 (2-) can regulatethe electronic structure of NiO, thus optimizing the free energy ofwater activation and hydrogen adsorption on the surface of NiO. Withthese advantages, the SeO3 (2-)-NiO catalystgenerated from in situ cathodic reconstruction exhibits satisfactoryHER performance. Precatalyst reconstruction in alkaline hydrogen evolutionreaction(HER) usually leads to changes in the morphology, composition, andstructure, thus improving the catalytic activity, which recently receivesintensive attention. However, the design strategies of cathodic reconstructionand the structural features of reconstruction products have not achieveda profound understanding. Here, from the point of thermodynamic stability,metastable nickel selenite dihydrate (NiSeO3 center dot 2H(2)O) is deliberately fabricated as a precatalyst to comprehensivelystudy the reconstruction dynamics in alkaline HER. Multiple in/exsitu techniques capture the geometric, component, and phase evolutions,proving that NiSeO3 center dot 2H(2)O can be transformedinto SeO3 (2-)-decorated polycrystallineNiO nanosheets with rich active sites and good conductivity underalkaline HER conditions, which act as a real catalytic active species.Density functional theory calculations demonstrate that the adsorptionof SeO3 (2-) can further promote the HERactivity of NiO due to the optimized free energy of water activationand hydrogen adsorption. As a result, the SeO3 (2-)-NiO catalyst exhibits a low overpotential at -10 mA cm(-2) (90 mV) and long-term stability (>100 h). Thisworkhighlights the targeted design of precatalyst to trigger and utilizecathodic reconstruction and provides an available method for the developmentof adsorption-modulated efficient electrocatalysts.

Water pollutants existing in their oxyanion forms have high solubility and environmental mobility. To capture these anionic pollutants, cost-effective inorganic materials with cationic frameworks and outstanding removal performance are ideal adsorbents. Herein, we report that two-dimensional (2D) cationic aluminoborate BAC(10) sets a new paradigm for highly selective and efficient capture of Cr(VI) and other oxyanions from aqueous solution. The structure of Cr(VI)-exchanged BAC(10) sample (Cr (VI )@BAC(10), H0.22 center dot Al2BO4.3 center dot(HCrO4)0.22 center dot 2.64H2O) has been successfully solved by continuous rotation electron diffraction. The crystallographic data show that the 2D cationic layer of BAC(10) is built by AlO6 octahedra, BO4 tetrahedra, and BO3 triangles. Partial chromate ions exchanged with Cl- ions are located within the interlayer region, which are chemically bonded to the aluminoborate layer. BAC(10) shows faster adsorption kinetics compared to the commercial anion exchange resin (AER) and layered double hydroxides (LDHs), a higher maximum adsorption capacity of 139.1 mg/g than that of AER (62.77 mg/g), LDHs (81.43 mg/g), and a vast majority of cationic MOFs, and a much broader working pH range (2-10.5) than LDHs. Moreover, BAC(10) also shows excellent Cr(VI) oxyanion removal performance for a solution with a low concentration (1-10 mg/L), and the residual concentration can be reduced to below 0.05 mg/L of the WHO drinking water criterion. These superior properties indicate that BAC(10) is a promising material for remediation of Cr(VI) and other harmful oxyanions from wastewater.

The SiO ₂ /Al ₂ O ₃ ratio of zeolites was improved by addition of NaI due to the promotion of I ⁻ for the formation of Si–O–Si bonds and the inhibition of I ⁻ for the formation of Si–O–Al bonds.

Crystalline aluminosilicate zeolites with high sorption capacity and low production cost have been recognized as a promising adsorbent for volatile organic compounds (VOCs) capture. However, the ubiquitous water vapour in the VOCs streams may compete with VOCs during the practical separation process because of the hydrophilic property of aluminosilicate zeolites. Herein, a self-supporting core-shell structured MFI-type zeolite monolith was fabricated by 3D printing aluminosilicate ZSM-5 zeolites as the core, followed by coating silicalite-1 zeolites as hydrophobic shell via post-hydrothermal crystallization. Natural sepiolite nanofibers (SNFs) were employed as printing ink additives for reinforcing the mechanical stability of 3D-printed ZSM-5 monoliths (3D-ZMs). Colloidal silica was also introduced into the printing inks affording continuous growth of silicalite-1 layers (with the thickness of ca. 200 nm) over ZSM-5 crystals. Such core-shell structured MFI-type zeolite monoliths exhibited superior dynamic adsorption performance for toluene at 298 K under humid conditions (relative humidity: 50%), with a saturated adsorption capacity of 44.3 mg/g. This work provides a facile strategy for designing self-supporting zeolite monoliths with core-shell architectures for adsorption/separation and other advanced applications.

3D‐printing technology is a promising approach for rapidly and precisely manufacturing zeolite adsorbents with desirable configurations. However, the trade‐off among mechanical stability, adsorption capacity, and diffusion kinetics remains an elusive challenge for the practical application of 3D‐printed zeolites. Herein, a facile “3D printing and zeolite soldering” strategy is developed to construct mechanically robust binder‐free zeolite monoliths (ZM‐BF) with hierarchical structures, which can act as a superior configuration for CO₂ capture. Halloysite nanotubes are employed as printing ink additives, which serve as both reinforcing materials and precursor materials for integrating ZM‐BF by ultrastrong interfacial “zeolite‐bonds” subjected to hydrothermal treatment. ZM‐BF exhibits outstanding mechanical properties with robust compressive strength up to 5.24 MPa, higher than most of the reported structured zeolites with binders. The equilibrium CO₂ uptake of ZM‐BF reaches up to 5.58 mmol g⁻¹ (298 K, 1 bar), which is the highest among all reported 3D‐printed CO₂ adsorbents. Strikingly, the dynamic adsorption breakthrough tests demonstrate the superiority of ZM‐BF over commercial benchmark zeolites for flue gas purification and natural gas and biogas upgrading. This work introduces a facile strategy for designing and fabricating high‐performance hierarchically structured zeolite adsorbents and even catalysts for practical applications.

Functionalization of porous titanium alloy implants with bioactive coatings to improve bone regeneration performance is hotly pursued in recent decade. Here we demonstrate a facile strategy to design bioactive 3D printed porous titanium implants with strontium (Sr) ion incorporated zeolite coatings (SZCs). The SZCs can be uniformly fabricated on the 3D porous scaffolds using an in situ hydrothermal crystal growth method to improve their osteogenesis and osteointegration capacity. In vitro experiments of SZCs on a TC4 disk show that Sr ions can slowly release in the simulated body fluid by means of ion-exchange, thus can drastically improve apatite forming ability, biocompatibility, corrosion resistance, and alkaline phosphatase (ALP) activity. In vivo evaluation on a rabbit model with 3D printed titanium implants shows that the SZCs could significantly induce new bone formation both in and around the porous implants within four weeks. This work may open up a new method for the development of bioactive customized porous implants by functionalization with zeolite coatings for orthopedic applications.