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The electrochemical activity and stability of multimetallic nanomaterials can be improved by adjusting the structure, morphology, and composition. Herein, trimetallic AuAgPt nanowires (AuAgPt-NWs) are achieved by the galvanic replacement reaction (GRR). The corrugated one-dimensional structure of AuAgPt-NWs increases catalytically active sites and improves chemical stability. Meanwhile, the special localized surface plasmon resonance (LSPR) response of Au nanomaterials further enhances their electrocatalytic activity under light irradiation conditions. For the formic acid oxidation reaction, Au6.4Ag2.6Pt1.0-NWs exhibit a high mass activity (3081.25 mA mgpt−1), which is 24.4 times higher than that of commercial Pt nanoparticles (126.38 mA mgpt−1). Au6.4Ag2.6Pt1.0-NWs also show enhanced electrocatalytic activity relative to commercial Pt nanoparticles for the hydrogen evolution reaction at 10 mA cm−2. Under light conditions, the electrolysis system of Au6.4Ag2.6Pt1.0-NWs only needs a voltage of 0.33 V to achieve H2 production, which originates from the excellent bifunctional electrocatalytic performance of Au6.4Ag2.6Pt1.0-NWs and the photothermal effect caused by LSPR. [ABSTRACT FROM AUTHOR]

It is of great challenge to produce highly pure C2H2 from the CO2/C2H2 mixture because of their similar physical properties. Metal–organic frameworks (MOFs) have shown great potential in purifying C2H2 by virtue of their versatile pore environment with excellent tunability. However, the rational exploration of ideal MOF adsorbents with CO2-preferred CO2/C2H2 separation performance (also called inverse C2H2/CO2 separation) is extremely difficult. In this work, we demonstrate a new Zn-MOF family (SNNU-334–336) with special CO2-preferred CO2/C2H2 separation performance, which can be rationally controlled by functional groups as well as temperature. Notably, SNNU-334–336 MOFs show extremely high stability, and SNNU-336 can maintain a stable structure even after 7 days in boiling water and 30 days in air, which is unprecedented for all Zn-based MOF materials. Different to common MOF adsorbents, the adsorption isotherms of SNNU-334–336 MOFs for C2H2 and CO2 under the same temperature all have an intersection point (we called the inverse point), which gradually moves to the high-pressure region with the increase of temperature and changes with the pore environment variation. So, SNNU-334–336 MOFs can be rationally controlled from C2H2-selective to CO2-selective CO2/C2H2 adsorption separation adsorbents. IAST selectivity calculation indicates that a very high CO2 over C2H2 selectivity (3595.4) can be achieved, which nearly surpasses those of all reported MOFs with CO2-preferred CO2/C2H2 separation performance. Fixed-bed column breakthrough experiments further prove that SNNU-334–336 MOFs all have controllable inverse CO2/C2H2 separation ability and can produce C2H2 with extra-high purity (>99.9%) from the CO2/C2H2 (1/99) mixture. [ABSTRACT FROM AUTHOR]

The controllable synthesis of highly stable porous metal–organic frameworks (MOFs) with targeted functions is urgently needed but still challenging up to now. In this work, we report the latest achievement in our continuous quest for robust 9-connected (9-c) MOFs based on [M3(O/OH)(COO)6(pyridine)3] building blocks. Different from the reported nets (ncb, xmz and pacs-MOFs) constructed from integrated or separated carboxylate and pyridine ligands, our metal–organic linker (MOL) strategy led to the discovery of six fascinating 9-c MOFs (SNNU-51–56) showing two types of completely new topological nets generated by cis, trans-coordination isomerism. As expected from highly connected architectures and the absence of open metal sites, all these MOFs show high thermal and moisture stability. They can even retain their frameworks after being treated at different pH values for 24 h. Furthermore, SNNU-51–56 not only inherit the excellent gas uptake performance of robust 9-c MOFs, but also exhibit extremely high CH4 separation from CO2, C2H2 and C2H4. Together with robust frameworks, the effective inner-cluster redox process in [M3(OH)(COO)6(pyridine)3] (M = Fe, Co and Ni) units makes SNNU-51–56 high-performance electrochemical pseudocapacitor materials. The asymmetric supercapacitor (ASC) fabricated with the SNNU-52 positive electrode and activated carbon (AC) negative electrode can be reversibly charged/discharged in a working voltage range of 0–1.6 V in 2 M KOH aqueous electrolyte for application in practical energy storage devices, and two serially connected ASCs can continuously light a light emitting diode. In all, greater control over the MOF structure, excellent thermal and chemical stability, and superb metal compatibility make [M3(O/OH)(COO)6(pyridine)3] clusters an ideal building block to design multifunctional MOF materials in the future. [ABSTRACT FROM AUTHOR]