Electrochemical activation of dinitrogen (N) is notoriously challenging, typically yielding very low ammonia (NH) production rates. In this study, we present a continuous flow plasma-electrochemical reactor system for the direct conversion of nitrogen from air into ammonia. In our system, nitrogen molecules are first converted into a mixture of NO species in the plasma reactor, which are then fed into an electrochemical reactor.
View Article and Find Full Text PDFACS Appl Mater Interfaces
January 2024
This article demonstrates spatial mapping of the local and nanoscale structure of thin film objects using spatially resolved pair distribution function (PDF) analysis of synchrotron X-ray diffraction data. This is exemplified in a lab-on-chip combinatorial array of sample spots containing catalytically interesting nanoparticles deposited from liquid precursors using an ink-jet liquid-handling system. A software implementation is presented of the whole protocol, including an approach for automated data acquisition and analysis using the atomic PDF method.
View Article and Find Full Text PDFUpgrading carbon dioxide/monoxide to multi-carbon C products using renewable electricity offers one route to more sustainable fuel and chemical production. One of the most appealing products is acetate, the profitable electrosynthesis of which demands a catalyst with higher efficiency. Here, a coordination polymer (CP) catalyst is reported that consists of Cu(I) and benzimidazole units linked via Cu(I)-imidazole coordination bonds, which enables selective reduction of CO to acetate with a 61% Faradaic efficiency at -0.
View Article and Find Full Text PDFHigh proton conductivity originated from its small size and the diffusion-free Grotthuss mechanism offers immense promise for proton-based magneto-ionic control of magnetic materials. Despite such promise, the realization of proton magneto-ionics is hampered by the lack of proton-responsive magnets as well as the solid-state sensing method. Here, we report the proton-based magneto-ionics in molecule-based magnet which serves as both solid-state proton battery electrode and radiofrequency sensing medium.
View Article and Find Full Text PDF2D magnets provoke a surge of interest in large anisotropy in reduced dimensions and are promising for next-generation information technology where dynamic magnetic tuning is essential. Until recently, the crucial metal-organic magnet Cr(pyz) ·xLiCl·yTHF with considerable high coercivity and high-temperature magnetic order opens up a new platform to control magnetism in metal-organic materials at room temperature. Here, an in-situ chemical tuning route is reported to realize the controllable transformation of low-temperature magnetic order into room-temperature hard magnetism in Cr(pyz) ·xLiCl·yTHF.
View Article and Find Full Text PDFMagneto-ionics, real-time ionic control of magnetism in solid-state materials, promise ultralow-power memory, computing, and ultralow-field sensor technologies. The real-time ion intercalation is also the key state-of-charge feature in rechargeable batteries. Here, we report that the reversible lithiation/delithiation in molecular magneto-ionic material, the cathode in a rechargeable lithium-ion battery, accurately monitors its real-time state of charge through a dynamic tunability of magnetic ordering.
View Article and Find Full Text PDFRealizing van der Waals (vdW) epitaxy in the 1980s represents a breakthrough that circumvents the stringent lattice matching and processing compatibility requirements in conventional covalent heteroepitaxy. However, due to the weak vdW interactions, there is little control over film qualities by the substrate. Typically, discrete domains with a spread of misorientation angles are formed, limiting the applicability of vdW epitaxy.
View Article and Find Full Text PDFACS Appl Mater Interfaces
March 2022
Zinc-air batteries are a promising alternative to lithium ion batteries due to their large energy density, safety, and low production cost. However, the stability of the zinc-air battery is often low due to the formation of dendrite which causes short circuiting and the CO adsorption from the air which causes carbonate formation on the air electrode. In this work, we demonstrate a zinc-air battery design with acidic oxygen reduction reaction for the first time via the incorporation of a bipolar membrane.
View Article and Find Full Text PDFThermal insulation of solid materials originates from the nanoscale porous architectures to regulate thermal management in energy-critical applications from energy-efficient buildings to heat-sensitive energy devices. Here, we show nanoengineering of porous silica materials to control the architecture transition from mesoporous to nanocage networks. A low thermal conductivity of such a porous silica network is achieved at 0.
View Article and Find Full Text PDFNitrogen-doped graphene-supported single atoms convert CO to CO, but fail to provide further hydrogenation to methane - a finding attributable to the weak adsorption of CO intermediates. To regulate the adsorption energy, here we investigate the metal-supported single atoms to enable CO hydrogenation. We find a copper-supported iron-single-atom catalyst producing a high-rate methane.
View Article and Find Full Text PDFCharge carrier transport in colloidal quantum dot (CQD) solids is strongly influenced by coupling among CQDs. The shape of as-synthesized CQDs results in random orientational relationships among facets in CQD solids, and this limits the CQD coupling strength and the resultant performance of optoelectronic devices. Here, colloidal-phase reconstruction of CQD surfaces, which improves facet alignment in CQD solids, is reported.
View Article and Find Full Text PDFIn the problem of electrochemical CO reduction, the discovery of earth-abundant, efficient, and selective catalysts is essential to enabling technology that can contribute to a carbon-neutral energy cycle. In this study, we adapt an optical high throughput screening method to study multi-metallic catalysts for CO electroreduction. We demonstrate the utility of the method by constructing catalytic activity maps of different alloyed elements and use X-ray scattering analysis by the atomic pair distribution function (PDF) method to gain insight into the structures of the most active compositions.
View Article and Find Full Text PDFElectrolysis offers an attractive route to upgrade greenhouse gases such as carbon dioxide (CO) to valuable fuels and feedstocks; however, productivity is often limited by gas diffusion through a liquid electrolyte to the surface of the catalyst. Here, we present a catalyst:ionomer bulk heterojunction (CIBH) architecture that decouples gas, ion, and electron transport. The CIBH comprises a metal and a superfine ionomer layer with hydrophobic and hydrophilic functionalities that extend gas and ion transport from tens of nanometers to the micrometer scale.
View Article and Find Full Text PDFThe electrocatalytic reduction of carbon dioxide, powered by renewable electricity, to produce valuable fuels and feedstocks provides a sustainable and carbon-neutral approach to the storage of energy produced by intermittent renewable sources. However, the highly selective generation of economically desirable products such as ethylene from the carbon dioxide reduction reaction (CORR) remains a challenge. Tuning the stabilities of intermediates to favour a desired reaction pathway can improve selectivity, and this has recently been explored for the reaction on copper by controlling morphology, grain boundaries, facets, oxidation state and dopants.
View Article and Find Full Text PDFThe electrochemical reduction of CO has seen many record-setting advances in C productivity in recent years. However, the selectivity for ethanol, a globally significant commodity chemical, is still low compared to the selectivity for products such as ethylene. Here we introduce diverse binding sites to a Cu catalyst, an approach that destabilizes the ethylene reaction intermediates and thereby promotes ethanol production.
View Article and Find Full Text PDFThe anomalously high mobility of hydroxide and hydronium ions in aqueous solutions is related to proton transfer and structural diffusion. The role of counterions in these solutions, however, is often considered to be negligible. Herein, we explore the impact of alkali metal counter cations on hydroxide solvation and mobility.
View Article and Find Full Text PDFThe solid-electrolyte interphase (SEI) is pivotal in stabilizing lithium metal anodes for rechargeable batteries. However, the SEI is constantly reforming and consuming electrolyte with cycling. The rational design of a stable SEI is plagued by the failure to control its structure and stability.
View Article and Find Full Text PDFSolid-state Li metal battery technology is attractive, owing to the high energy density, long lifespans, and better safety. A key obstacle in this technology is the unstable Li/solid-state electrolyte (SSE) interface involving electrolyte reduction by Li. Herein we report a novel approach based on the use of a nanocomposite consisting of organic elastomeric salts (LiO-(CH O) -Li) and inorganic nanoparticle salts (LiF, -NSO -Li, Li O), which serve as an interphase to protect Li GeP S (LGPS), a highly conductive but reducible SSE.
View Article and Find Full Text PDFIt is of great interest and big challenge to control the collective behaviors of nanomotors to mimic the aggregation/separation behavior of biological systems. Here, a light-acoustic combined method is proposed to control the aggregation/separation of artificial nanomotors. It is shown that nanomotors aggregate at the pressure node in acoustic field and afterward present a collective "firework" separation behavior induced by light irradiation.
View Article and Find Full Text PDFLi-alloy-based anode materials are very promising for breaking current energy limits of lithium-ion battery technologies. Unfortunately, these materials still suffer from poor solid-electrolyte interphase (SEI) stability, resulting in unsatisfied electrochemical performances. The typical SEI formation method, electrochemical decomposition of electrolytes onto the active material surface, lacks a deliberate control of the SEI functions and structures.
View Article and Find Full Text PDFThe lithium (Li) metal anode suffers severe interfacial instability from its high reactivity toward liquid electrolytes, especially carbonate-based electrolytes, resulting in poor electrochemical performance of batteries that use 4 V high-capacity cathodes. We report a new skin-grafting strategy that stabilizes the Li metal-liquid electrolyte interface by coating the Li metal surface with poly((N-2,2-dimethyl-1,3-dioxolane-4-methyl)-5-norbornene-exo-2,3-dicarboximide), a chemically and electrochemically active polymer layer. This layer, composed of cyclic ether groups with a stiff polycyclic main chain, serves as a grafted polymer skin on the Li metal anode not only to incorporate ether-based polymeric components into the solid-electrolyte interphase (SEI) but also to accommodate Li deposition/dissolution under the skin in a dendrite/moss-free manner.
View Article and Find Full Text PDFChem Commun (Camb)
October 2017
We report the synthesis and properties of rod-shaped gold/iron oxide nanomotors that are powered by visible light in dilute hydrogen peroxide solutions. Electrochemical measurements confirmed that the light-driven nanomotors operate by a self-electrophoretic mechanism, modulated by the photovoltage and the photoconductivity of gold/iron oxide. Due to the magnetism of iron oxide, the nanomotors can be steered by an external magnetic field without incorporating additional magnetic materials into the nanomotors.
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