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Mercury is one of the most toxic heavy metals that can cause terrible disease for human beings. Among different absorption materials, MOF (metal-organic framework) materials show potential as very attractive materials for the rapid removal of mercury. However, the instability and difficulty for regeneration of MOF crystals limit their applications. Here, a continuous sulfur-modified MOF (UiO-66-NHC(S)NHMe) layer was synthesized in situ on polymeric membranes (PP non-woven fabrics) by post-synthetic modification and used for rapid mercury removal. The MOF-based membrane (US-N) showed high selectivity for mercury in different aqueous systems, which is better than sulfur-modified MOF powders. A thinner MOF layer on US-N showed a much better mercury ion removal performance. US-N with a 59.3 nm MOF layer could remove more than 85% of mercury in 20 min from an aqueous solution. In addition, the US-N can simply regenerate several times for mercury removal and maintain the initial performance (removal ratio > 98%), exhibiting excellent durability and stability. This work promotes the application of MOF materials in the rapid removal of hazardous heavy metal ions from practical environments.

A novel photosensitizer (PS) was developed by anchoring an Ir(iii) complex on a macroscopic polymer substrate to prevent ligand dissociation of the PS, resulting in a long duration of over 730 h in photocatalytic hydrogen evolution. This study paves the way for designing new Ir(iii) PSs and exploring the inactivation mechanism of PSs.

In this paper, we successfully controllably synthesize continuous nanothickness MOF coatings (NTMCs) by a layer-by-layer method on a polymeric substrate. The polymeric substrate was pretreated with high energy γ-irradiation to induce a high surface density of living reactive groups, which ensure the formation of continuous surface-integrated NTMCs. SEM, FT-IR spectroscopy and XPS were used to characterize NTMCs. The thickness and morphology were tuned by the LBL cycles, and NTMCs with a thickness of ∼44 nm were obtained. The chemical bonds between the NTMCs and polymeric substrate were confirmed by XPS and EDS. Moreover, the NTMCs exhibit good performance for oil-water separation. We believe that our work will promote the design and precise synthesis of high-performance MOF based membranes for multiple practical applications in future.

In this article, a new kind of anti-icing material, liquid-infused micro-nanostructured MOF coating (LIMNSMC), was designed and prepared. The porous micro-nanostructures of metal-organic framework (MOF) coating were first utilized to immobilize the lubricating liquid. The anti-icing performance of LIMNSMC could be tuned by the viscosity, the amount of lubricating liquid, and the surface morphology. Under appropriate conditions, the LIMNSMC shows high anti-icing performance with the condensed water-freezing temperature of approximately -39 °C and the ice adhesion strength of approximately 10 kPa as the micro-nanostructures of MOF coating reduce the contact area and hinder the heat transfer between the surface and water droplets, and the lubricating layer effectively reduces the heterogeneous nucleation sites on the surface, as well as reduces the ice adhesion. LIMNSMCs exhibit good durability as the lubricating liquid can be effectively immobilized by the nanopores of MOFs. So, the high anti-icing performance of LIMNSMCs could be maintained throughout 10 freezing/melting cycles and six icing/de-icing cycles and slightly decreased after high-speed centrifugation and 50 abrasion cycles.

In this work, a series of heptaphenyl siloxane trisilanol/polyhedral oligomeric silsesquioxane (T₇-POSS) modified by polyols with different molecular weights were synthesized into liquid-like nanoparticle⁻organic hybrid materials using the grafted-from method. All grafted POSS nanoparticles changed from solid powders to liquid at room temperature. Polyurethane (PU) nanocomposites with POSS contents ranging from 1.75 to 9.72 wt % were prepared from these liquefied polyols-terminated POSS with polyepichlorohydrin (POSS–PECH). Transmission electron microscopy (TEM), scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS) were used to characterize the morphology of the POSS–PECH/PU nanocomposites. The results showed that the polyol-terminated POSS particles overcame the nanoagglomeration effect and evenly disperse in the polymeric matrix. The damping factor (tan δ ) of resultant nanocomposites increased from 0.90 to 1.16, while the glass transition temperature decreased from 15.8 to 9.4 °C when POSS contents increased from 0 to 9.75 wt %. The gel content, tensile strength and Fourier transform infrared (FTIR) analyses demonstrated that the molecular thermal movement ability of the polyurethane (PU) matrix increased with increasing POSS hybrid content. Therefore, the improvement of the damping properties of the composites was mainly due to the friction-related losses occurring in the interface region between the nanoparticles and the matrix.

This paper investigates the required properties of Ru-coordinated ligands of a Ni-Ru based hydrogenase mimic. A series of ligands, including MeCN, pyridine, H(2)O and OH(-) were coordinated to Ru, with H(2)O being the only ligand to promote H(2)-activation. In addition, a tethered pyridyl moiety was synthesised and found to completely inhibit H(2)-activation. We conclude, therefore, that H(2)O is the ideal ligand for this mimic as a result of both its mild basicity and the availability of two lone pairs for simultaneous binding to Ru and H(2).