Metal−organic frameworks (MOFs), as newly emerging materials, show compelling intrinsic structural features, e.g., the highly crystalline nature and designable and tunable porosity, as well as tailorable functionality, rendering them suitable for proton-conducting materials. The proton conduction of MOF is significantly improved using the postsynthesis or encapsulation strategy. In this work, the MOF-based proton-conducting material Im@MOF-808 has been prepared by incorporating the imidazole molecules into the pores of proton-conducting MOF-808. Compared with MOF-808, Im@MOF-808 not only possesses higher proton conductivity of 3.45 × 10 −2 S cm −1 at 338 K and 99% RH, superior to that of any imidazoleencapsulated proton-conducting materials reported to date, but also good durable and stable proton conduction. Moreover, the thermal stability of Hbond networks is much improved owing to the water molecules partially replaced by higher boiling point imidazole molecules. Additionally, it is further discussed for the possible mechanism of imidazole encapsulation into the pores of MOF-808 to enhance proton conduction.

Proton-exchange membranes (PEMs), characterized by selectively permitting the transfer of protons and acting as a separator in electrochemical devices, have attracted immense attention. The composite membrane, fabricated from organic polymer matrix and high proton-conducting metal-organic framework (MOF), integrates the excellent physical and chemical performances of the polymer and MOF, achieving collective properties for good-performance PEMs. In this study, we demonstrate that MOF-801 shows remarkable proton conductance with σ = 1.88 × 10 S cm at 298 K and 98% relative humidity (RH), specifically, together with extra stability to hydrochloric acid or diluting sodium hydroxide aqueous solutions and boiling water. Furthermore, the composite membranes (denoted MOF-801@PP- X, where X represents the mass percentage of MOF-801 in the membrane) have been fabricated using the sub-micrometer-scale crystalline particles of MOF-801 and blending the poly(vinylidene fluoride)-poly(vinylpyrrolidone) matrix, and these PEMs display high proton conductivity, with σ = 1.84 × 10 S cm at 325 K 98% RH. A composite membrane as PEM was assembled into H/O fuel cell for tests, indicating that these membrane materials have vast potential for PEM application on electrochemical devices.

We previously identified and characterized a novel p53-regulated gene in mouse prostate cancer cells that was homologous to a human gene that had been identified in brain cancers and termed RTVP-1 or GLIPR. In this report, we document that the human RTVP-1 gene is also regulated by p53 and induces apoptosis in human prostate cancer cell lines. We show that the expression of the human RTVP-1 gene is down-regulated in human prostate cancer specimens compared with normal human prostate tissue at the mRNA and protein levels. We further document epigenetic changes consistent with RTVP-1 being a tumor suppressor in human prostate cancer.

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Organic color center-tailored semiconducting single-walled carbon nanotubes are a rising family of synthetic quantum emitters that display bright defect photoluminescence molecularly tunable for imaging, sensing, and quantum information processing. A major advance in this area would be the development of a high-yield synthetic route that is capable of producing these materials well exceeding the current μg/mL scale. Here, we demonstrate that adding a chlorosulfonic acid solution of raw carbon nanotubes, sodium nitrite, and an aniline derivative into water readily leads to the synthesis of organic color center-tailored nanotubes. This unexpectedly simple one-pot reaction is highly scalable (yielding hundreds of milligrams of materials in a single run), efficient (reaction completes in seconds), and versatile (achieved the synthesis of organic color centers previously unattainable). The implanted organic color centers can be easily tailored by choosing from the more than 40 aniline derivatives that are commercially available, including many fluoroaniline and aminobenzoic acid derivatives, and that are difficult to convert into diazonium salts. We found this chemistry works for all the nanotube chiralities investigated. The synthesized materials are neat solids that can be directly dispersed in either water or an organic solvent by a surfactant or polymer depending on the specific application. The nanotube products can also be further sorted into single chirality-enriched fractions with defect-specific photoluminescence that is tunable over ∼1100 to ∼1550 nm. This one-pot chemistry thus provides a highly scalable synthesis of organic color centers for many potential applications that require large quantities of materials.

Aryl diazonium reactions are widely used to covalently modify graphitic electrodes and low-dimensional carbon materials, including the recent creation of organic color centers (OCCs) on single-wall carbon nanotube semiconductors. However, due to the experimental difficulties in resolving small functional groups over extensive carbon lattices, a basic question until now remains unanswered: what group, if any, is pairing with the aryl sp 3 defect when breaking a C�C bond on the sp 2 carbon lattice? Here, we show that water plays an unexpected role in completing the diazonium reaction with carbon nanotubes involving chlorosulfonic acid, acting as a nucleophilic agent that contributes −OH as the pairing group. By simply replacing water with other nucleophilic solvents, we find it is possible to create OCCs that feature an entirely new series of pairing groups, including −OCH 3 , −OC 2 H 5 , −OC 3 H 7 , -i-OC 3 H 7 , and −NH 2 , which allows us to systematically tailor the defect pairs and the optical properties of the resulting color centers. Enabled by these pairing groups, we further achieved the synthesis of OCCs with sterically bulky pairs that exhibit high purity defect photoluminescence effectively covering both the second near-infrared window and the telecom wavelengths. Our studies further suggest that these diazonium reactions proceed through the formation of carbocations in chlorosulfonic acid, rather than a radical mechanism that typically occurs in aqueous solutions. These findings uncover the unknown half of the sp 3 defect pairs and provide a synthetic approach to control these defect color centers for quantum information, imaging, and sensing.

Metal–organic frameworks (MOFs) are excellent catalytic materials for the hydrolytic degradation of nerve agents and their simulants. However, most of the MOF-based hydrolysis catalysts to date are reliant on liquid water media buffered by a volatile liquid base. To overcome this practical limitation, we developed a simple and feasible strategy to synthesize MOF composites that structurally mimic phosphotriesterase’s active site as well as its ligated histidine residues. By incorporating imidazole and its derivative into the pores of MOF-808, the obtained MOF composites achieved rapid degradation of a nerve agent simulant (dimethyl-4-nitrophenyl phosphate, DMNP) in pure water as well as in a humid environment without liquid base. Remarkably, one of the composites Im@MOF-808 displayed the highest catalytic activity for DMNP hydrolysis in unbuffered aqueous solutions among all reported MOF-based catalysts. Furthermore, solid-phase catalysis showed that Im@MOF-808 can also rapidly hydrolyze DMNP under high-humidity conditions without bulk water or external bases. This work provides a viable solution toward the implementation of MOF materials into protective equipment for practical nerve agent detoxification.

Metal−organic frameworks (MOFs) provided a versatile platform for the development of new solid protonic electrolytes but faced great challenges regarding their low chemical stability and poor moisture retention capacity. Herein, we presented the proton-conducting study for zirconium-based MOF-802, revealing that MOF-802 possessed excellent features of extra aqueous and acidic stabilities and room-temperature superprotonic conduction with a proton conductivity of 1.05 × 10 −2 S cm −1 at 288 K under 98% relative humidity (RH). Unfortunately, due to the liberation of water molecules from pores/channels, the proton conductivity of MOF-802 dropped significantly at the temperature above 318 K. To solve this issue, for the first time, MOF-802 was hybridized with poly(vinyl alcohol) (PVA) to form MOF-802@PVA hydrogel composites, where the moisture retention capacity of MOF-802 was greatly improved, giving the high room-temperature proton conductivity over 10 −3 S cm −1 under ambient humidity. This work paves a new way to improve the moisture retention capacity and proton-conducting performances of porous proton conductors.