Scalable, Flexible, and UV-Resistant Bacterial Cellulose Composite Film for Daytime Radiative Cooling.

Radiative cooling, a passive cooling technology, functions by reflecting the majority of solar radiation (within the solar spectrum of 0.3-2.5 μm) and emitting thermal radiation (within the atmospheric windows of 8-13 μm and 16-20 μm).

One-pot synthesis of supported sub-micron LaNi for hydrogen storage in a carbazole-type liquid organic hydrogen carrier.

Metal hydrides are promising catalysts in hydrogen-involving reactions. However, downsizing and loading metal hydrides is difficult due to their sensitivity towards oxygen and water. Here, a simple one-pot molten salt synthetical method is proposed to synthesize porous La(OH)-supported LaNi.

Achieving Superior Cyclability Pouch Cells with Oxygen Vacancy-Moderated P'2/P3 Hybrid Layered Sodium Cathode Materials.

Layered P2-type sodium manganese oxide has emerged as a promising cathode candidate for sodium-ion batteries due to its appealing cost-effectiveness and high discharge voltage. However, its practical capacity within the voltage range of 2.0-4.

Phase Transition Modulated by Grain Size and Lattice Distortion in Layered Transition Metal Oxide for Sodium-Ion Batteries.

Low-cost sodium-ion batteries have demonstrated great prospects in energy storage, among which layered transition metal oxides hold great potential as a cathode material. However, the notorious phase transition in layered cathode materials has greatly hampered their cycle life due to large volume changes upon desodiation/sodiation. In this study, by adopting an O3-type NaNiFeMnO (NFM) with controlled synthesis temperatures, we have revealed that the grain size is closely related to its phase transition behaviors.

Alloying Pd with Ru enables electroreduction of nitrate to ammonia with ∼100% faradaic efficiency over a wide potential window.

Electrocatalytic nitrate (NO) reduction reaction (eNORR) to ammonia under ambient conditions is deemed a sustainable route for wastewater treatment and a promising alternative to the Haber-Bosch process. However, there is still a lack of efficient electrocatalysts to achieve high NH production performance at wastewater-relevant low NO concentrations. Herein, we report a PdRu bimetallic nanocrystal (NC) electrocatalyst capable of exhibiting an average NH FE of ∼100% over a wide potential window from 0.

Balanced NO and Proton Adsorption for Efficient Electrocatalytic NO to NH Conversion.

Electrocatalytic nitrate (NO)/nitrite (NO) reduction reaction (eNORR) to ammonia under ambient conditions presents a green and promising alternative to the Haber-Bosch process. Practically available NO sources, such as wastewater or plasma-enabled nitrogen oxidation reaction (p-NOR), typically have low NO concentrations. Hence, electrocatalyst engineering is important for practical eNORR to obtain both high NH Faradaic efficiency (FE) and high yield rate.

Integration of Metal-Organic Frameworks and Metals: Synergy for Electrocatalysis.

Electrocatalysis is a highly promising technology widely used in clean energy conversion. There is a continuing need to develop advanced electrocatalysts to catalyze the critical electrochemical reactions. Integrating metal active species, including various metal nanostructures (NSs) and atomically dispersed metal sites (ADMSs), into metal-organic frameworks (MOFs) leads to the formation of promising heterogeneous electrocatalysts that take advantage of both components.

Achieving Tunable Selectivity and Activity of CO Electroreduction to CO via Bimetallic Silver-Copper Electronic Engineering.

Limited comprehension of the reaction mechanism has hindered the development of catalysts for CO reduction reactions (CO RR). Here, the bimetallic AgCu nanocatalyst platform is employed to understand the effect of the electronic structure of catalysts on the selectivity and activity for CO electroreduction to CO. The atomic arrangement and electronic state structure vary with the atomic ratio of Ag and Cu, enabling tunable d-band centers to optimize the binding strength of key intermediates.

Temperature-Induced Structure Transformation from CoSe to Orthorhombic Phase CoSe Realizing Enhanced Hydrogen Evolution Catalysis.

Transition-metal chalcogenides (TMC) have been widely studied as active electrocatalysts toward the hydrogen evolution reaction due to their suitable d-electron configuration and relatively high electrical conductivity. Herein, we develop a feasible method to synthesize an orthorhombic phase of CoSe (o-CoSe) from the regeneration of CoSe, where the temperature plays a key role in controlling the structure transformation. To the best of our knowledge, this is the first report about this synthetic route for o-CoSe.

Enhanced Electrochemical Reduction of CO to CO on Ag/SnO by a Synergistic Effect of Morphology and Structural Defects.

Silver (Ag)-based materials are considered to be promising materials for electrochemical reduction of CO to produce CO, but the selectivity and efficiency of traditional polycrystalline Ag materials are insufficient; there still exists a great challenge to explore novel modified Ag based materials. Herein, a nanocomposite of Ag and SnO (Ag/SnO ) for efficient reduction of CO to CO is reported. HRTEM and XRD patterns clearly demonstrated the lattice destruction of Ag and the amorphous SnO in the Ag/SnO nanocomposite.

Planar Fully Stretchable Lithium-Ion Batteries Based on a Lamellar Conductive Elastomer.

Stretchable lithium-ion batteries (LIBs) have attracted great attention as a promising power source in the emerging field of wearable electronics. Despite the recent advances in stretchable electrodes, separators, and sealing materials, building stretchable full batteries remains a big challenge. Herein, a simple strategy to prepare stretchable electrodes and separators at the full battery scale is reported.

Palladium-Cobalt Nanowires Decorated with Jagged Appearance for Efficient Methanol Electro-oxidation.

Inexpensive, active, stable, and CO-tolerant nonplatinum catalysts for efficient methanol electro-oxidation are highly desirable to direct methanol fuel cell (DMFC) technology; however, it is still challenging. In this study, we report palladium and cobalt nanowires with jagged appearance (Pd-Co J-NWs), synthesized via first anodic-aluminum-oxide template-confined electrodeposition of Pd-Co regular nanowires, followed by a wet-chemical transformation. Benefiting from the "jagged" appearance and Co dopants, the mass and specific activities of Pd-Co J-NWs for methanol electro-oxidation are evaluated ∼3.

Building better lithium-sulfur batteries: from LiNO3 to solid oxide catalyst.

Lithium nitrate (LiNO3) is known as an important electrolyte additive in lithium-sulfur (Li-S) batteries. The prevailing understanding is that LiNO3 reacts with metallic lithium anode to form a passivation layer which suppresses redox shuttles of lithium polysulfides, enabling good rechargeability of Li-S batteries. However, this view is seeing more challenges in the recent studies, and above all, the inability of inhibiting polysulfide reduction on Li anode.

A strain or electric field induced direct bandgap in ultrathin silicon film and its application in photovoltaics or photocatalysis.

The indirect bandgap character of silicon greatly limits its applications in electronic or optoelectronic devices, and direct bandgaps are highly desirable in all silicon allotropes. The successful synthesis of ultrathin or even monolayer silicon films experimentally has opened new opportunities to further modulate the electronic structure of silicon through external modulation. In this work, strain or electric field effects on the electronic structure of ultrathin silicon film (USF) are systematically explored.

Manganese Oxide Catalyst Grown on Carbon Paper as an Air Cathode for High-Performance Rechargeable Zinc-Air Batteries.

Manganese oxide is grown directly on carbon paper through a simple immersion process, and used as a catalyst-modified air cathode for rechargeable zinc-air batteries. The manganese oxide is distributed evenly within the porous carbon paper, which promotes a rapid three-phase reaction and high utilization of the active materials. Zinc-air batteries with the manganese oxide catalyst directly grown on the carbon paper exhibit improved performance compared with zinc-air batteries fabricated by using manganese oxide powder catalyst coated on carbon paper.

Investigation on the Cyclability of Lithium-Oxygen Cells in a Confined Potential Window using Cathodes with Pre-filled Discharge Products.

With new chemistry and advantageous configuration, the lithium-oxygen (Li-O2) battery promises a much higher specific energy than traditional lithium-ion batteries. The limited understanding on the complicated battery reactions therein, however, has become a major bottleneck of its development for applications requiring a high energy efficiency and long cycle-life. Herein, in a confined potential window with negligible electrolyte degradation, we studied the rechargeability of Li-O2 cathodes with pre-filled well-defined discharge products of Li2O2, Li2CO3, LiOH, or their combinations.

Eggplant-derived microporous carbon sheets: towards mass production of efficient bifunctional oxygen electrocatalysts at low cost for rechargeable Zn-air batteries.

We report 2D microporous carbon sheets with high surface area, derived from eggplant via simple carbonization and KOH activation, as low cost yet efficient bifunctional catalysts for high performance rechargeable zinc-air batteries.

Co3O4 nanoparticles decorated carbon nanofiber mat as binder-free air-cathode for high performance rechargeable zinc-air batteries.

An efficient, durable and low cost air-cathode is essential for a high performance metal-air battery for practical applications. Herein, we report a composite bifunctional catalyst, Co3O4 nanoparticles-decorated carbon nanofibers (CNFs), working as an efficient air-cathode in high performance rechargeable Zn-air batteries (ZnABs). The particles-on-fibers nanohybrid materials were derived from electrospun metal-ion containing polymer fibers followed by thermal carbonization and a post annealing process in air at a moderate temperature.

N-containing functional groups induced superior cytocompatible and hemocompatible graphene by NH₂ ion implantation.

Graphene is functionalized with amine by NH2 ion implantation at room temperature in vacuum. The reaction is featured by nucleophilic substitution of C-O groups by the ammonia radicals. The presence of N-containing functional groups in graphene is identified by Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy.

NH2+ implantations induced superior hemocompatibility of carbon nanotubes.

NH2+ implantation was performed on multiwalled carbon nanotubes (MWCNTs) prepared by chemical vapor deposition. The hemocompatibility of MWCNTs and NH2+-implanted MWCNTs was evaluated based on in vitro hemolysis, platelet adhesion, and kinetic-clotting tests. Compared with MWCNTs, NH2+-implanted MWCNTs displayed more perfect platelets and red blood cells in morphology, lower platelet adhesion rate, lower hemolytic rate, and longer kinetic blood-clotting time.

Hierarchical nanostructured core-shell Sn@C nanoparticles embedded in graphene nanosheets: spectroscopic view and their application in lithium ion batteries.

Hierarchical carbon encapsulated tin (Sn@C) embedded graphene nanosheet (GN) composites (Sn@C-GNs) have been successfully fabricated via a simple and scalable one-step chemical vapor deposition (CVD) procedure. The GN supported Sn@C core-shell structures consist of a crystalline tin core, which is thoroughly covered by a carbon shell and more interestingly, extra voids are present between the carbon shell and the tin core. Synchrotron spectroscopy confirms that the metallic tin core is free of oxidation and the existence of charge redistribution transfer from tin to the carbonaceous materials of the shell, facilitating their intimate contact by chemical bonding and resultant lattice variation.

Facile controlled synthesis and growth mechanisms of flower-like and tubular MnO2 nanostructures by microwave-assisted hydrothermal method.

Birnessite flower-like and α-type tubular MnO(2) nanostructures were selectively synthesized through simple decomposition of KMnO(4) under hydrochloric acid condition by controlling reaction temperature using a microwave-assisted hydrothermal method. The as-prepared samples were characterized in detail by various techniques including X-ray diffraction, field emission scanning electron microscopy, transmission electron microscopy, high-resolution transmission electron microscopy, Fourier transform-infrared spectroscopy, and Raman scattering spectroscopy. While the growth of flower-like birnessite-MnO(2) might follow a widely accepted Ostwald ripening process, we proposed a formation mechanism of the nanotubular α-MnO(2) based on our evidence, which was assembly of nanorods through an "oriented attachment" process.

Light-activated covalent formation of gold nanoparticle-graphene and gold nanoparticle-glass composites.

Monolayer protected gold nanoparticles (AuNPs) modified with a 3-aryl-3-(trifluoromethyl)diazirine functionality at its terminus (Diaz-AuNPs, 3.9 nm) were prepared and irradiated in the presence of two very different substrates, reduced graphene and glass. Upon irradiation, the terminal diazirine group loses nitrogen to generate a reactive carbene at the interface of the AuNPs that can then undergo addition or insertion reactions with functional groups on the graphene or glass surfaces, leading to the formation of graphene-AuNP and glass-AuNP hybrids, respectively.

Superior energy capacity of graphene nanosheets for a nonaqueous lithium-oxygen battery.

Graphene nanosheets (GNSs) were synthesized and used as cathode active materials in a nonaqueous lithium-oxygen battery. The GNSs electrode delivered an extremely high discharge capacity in comparison to carbon powders, which is attributed to its unique morphology and structure.