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Photo-response molecular-scale movement has been well developed in azobenzene photochromic molecules. However, material capable of converting this molecular-scale movement to macroscopic work remains a formidable challenge. Here, we describe an exquisite photomechanical effect observed in an azobenzene-Gd(III) MOF. The single crystal of this material displays complex motion including walking, rolling, self-rotating, swing, and finally popping, dependent on the exposed time under UV and the size of the crystals. Consequently, this functional material gives the direct and impressive evidence to support the potential of MOF material in photomechanical motion.

Uranium is the most radioactive element using in the nuclear industry and nuclear technology application. However, it is harmful for environment and human health due to its high toxicity and mobility. Thus designing effective material for uranium removal is highly desirable. In this paper, a novel adsorbent of nZVI@Zn-MOF-74 prepared by anchoring nZVI on Zn-MOF-74 was investigated for the removal of uranium from aqueous solutions. Impressively, nZVI was synthesized for the first time by a spraying approach in a simple and convenient manner. The experimental results indicated that nZVI@Zn-MOF-74 can significantly enhance the removal of U(VI) than both Zn-MOF-74 material and nZVI, leading to high adsorption capacity up to 348 mg/g at pH = 3 and 298 K. The origin, as unveiled by XPS, is due to both U(VI) adsorption from Zn-MOF-74 and U(VI)-to-U(IV) reduction by nZVI.

Hydrogen-bonded frameworks (HOFs) with permanent microporosity are still hard to obtain, due to the inherent nature of easy-to-collapse of HOF skeleton on solvent removal. On the other hand, tuning the electronic structure of HOFs by incorporating redox-active units for expanding the functionality of this class of material presents a waiting-for unveiled and highly desired field. In this work, the redox-active imide unit was utilized to construct HOF. The resultant HOF (namely ECUT-HOF-30) enables robust microporous structure of ca. 4.0 Å, performing effective separation of C2H2/CO2 via the unique molecular recognition from imide oxygen atoms. Whilst exciting optoelectronic active properties such as photochromism and electrochromism were observed in this HOF. The proof-of-concept results open up a gate for fundamental design of advanced HOFs with redox-active unit and versatility.

In this work, we found that the open-metal site in a metal-organic framework (MOF) can be used to enhance such selectivity. Hydrogenation of phenylacetylene over such a catalyst enables ultrahigh styrene selectivity of 92% at full conversion with a turnover frequency of 98.1 h-1. The origin of ultrahigh selectivity, as unveiled by density functional theory calculation, is due to a coordination interaction between the open Zn(II) site and the C≡C bond of phenylacetylene.

Herein we report a novel azo metal-organic framework (MOF), namely Zn2(DMF)(ADC)2(L)0.5 (ECUT-100, H2ADC=azobenzene-4,4'-dicarboxylic acid, L=N, N'-di(pyridin-4-yl)naphthalene-1,4-dicarboxamide), showing a polycatenated 3D array of interlaced 2D bilayers. Without any pre-treatment the as-synthesized ECUT-100 samples effectively adsorb U(VI), leading to the ultrahigh adsorption capacity up to 381 mg/g. This value is greatly higher than that observed in most established porous adsorbents. The origin is primarily due to the free standing azo and amide groups from ADC2- and L ligands that may provide special interactions with U(VI) ions.

In this work, we designed a hybrid catalyst composed of a metal–organic framework (MOF), Pt nanoparticles (NPs), and ferric oxide, namely, Co-MOF-74@(Pt@Fe2O3), which enables not only high turnover frequencies of up to 245.7 h–1 but also ultrahigh 100% selectivity toward cinnamyl alcohol in the hydrogenation of cinnamaldehyde under mild conditions. This excellent performance is attributed to the fact that such a hybrid catalyst enables not only strong steric constraint to provide the favored C═O adsorption of cinnamaldehyde but also strong metal–support interaction to lower the electron density of Pt NPs.

Uranium is not only a radioactive element but also an important nuclear-energy source. Thus the design of material for effective uranium adsorption is highly desirable from both environmental and energy considerations. In this work, a new azo-MOF was explored such use. It shows excellent U(VI) removal performance with the adsorption capacity up to 200 mg/g. The adsorption, as disclosed by the adsorption kinetics, is dominated by chemical adsorption, mainly due to coordination interaction between azo/amide and U(VI) ions. The results suggest that design of material with free-standing azo or amide groups benefits to U(VI) removal.

We present here the first use of a photoassisted multicomponent postsynthetic modification method to anchor a ZIF-90 scaffold with a pyrimidinethione fragment. The resultant materials, namely, ZIF-90-THP and ZIF-90-THF, show ultrahigh Hg(II) adsorption capacity values of up to 596 and 403 mg/g, respectively, relative to the pristine ZIF-90, which just affords a corresponding value of 47 mg/g, suggesting a 12.7- and 8.6-fold enhancement in the Hg(II) adsorption capacity.

In this study, we present the first case of applying the MOF+ technique for in situ preparation of a hybrid material, namely, Zn-MOF-74@ (Pd@Fe2O3). This as-synthesized material can well maintain both the integrity of the framework and porosity. Notably, Zn-MOF-74@(Pd@Fe2O3) exhibits outstanding catalytic performance in the hydrogenation reaction of alkene and semihydrogenation reaction of phenylacetylene, thus providing a new guideline for the design of MOF-based hybrid materials for catalytic purpose.