仲云雷

Ultrathin black phosphorus nanodisks hybridized with Fe₃O₄ nanoclusters and iron (V)-oxo complex are rationally synthesized, and shown to exhibit ultrahigh stability in humid air, and competitive electrochemical potassium storage properties benefiting from unique structural and compositional merits.

Abstract

The practical application of metalloid black phosphorus (BP) based anodes for potassium ion batteries is mainly impeded by its instability in air and irreversible/sluggish potassium storage behaviors. Herein, a 2D composite is purposefully conceptualized, where ultrathin BP nanodisks with Fe₃O₄ nanoclusters are hybridized with Lewis acid iron (V)-oxo complex (FC) nanosheets (denoted as BP@Fe₃O₄-NCs@FC). The introduced electron coordinate bridge between FC and BP, and hydrophobic surface of FC synergistically assure that BP@Fe₃O₄-NCs@FC is ultrastable in humid air. With the purposeful structural and componential design, the resultant BP@Fe₃O₄-NCs@FC anode is endowed with appealing electrochemical performance in terms of reversible capacity, rate behavior, and long-duration cycling stability in both half and full cells. Furthermore, the underlying formation and potassium-storage mechanisms of BP@Fe₃O₄-NCs@FC are tentatively proposed. The in-depth insights here will provide a crucial understanding in rational exploration of advanced anodes for next-generation PIBs.

In this work, we report a novel architecture with FeP nanodots fully embedded in nitrogen doped carbon microplates skeleton (FeP@CMS) via the spatial confinement of carbon quantum dots (CQDs) . Such a structure allows the stress transfer between FeP nanodots and self-adaptive carbon matrix in sodium storage, which overcomes the intrinsic chemo-mechanical degradation of metal phosphides during long-term cycling.

Abstract

Transition-metal phosphides (TMPs) as typical conversion-type anode materials demonstrate extraordinary theoretical charge storage capacity for sodium ion batteries, but the unavoidable volume expansion and irreversible capacity loss upon cycling represent their long-standing limitations. Herein we report a stress self-adaptive structure with ultrafine FeP nanodots embedded in dense carbon microplates skeleton (FeP@CMS) via the spatial confinement of carbon quantum dots (CQDs). Such an architecture delivers a record high specific capacity (778 mAh g⁻¹ at 0.05 A g⁻¹) and ultra-long cycle stability (87.6 % capacity retention after 10 000 cycles at 20 A g⁻¹), which outperform the state-of-the-art literature. We decode the fundamental reasons for this unprecedented performance, that such an architecture allows the spontaneous stress transfer from FeP nanodots to the surrounding carbon matrix, thus overcomes the intrinsic chemo-mechanical degradation of metal phosphides.

Hierarchical silicon-based photocathodes with mixed-phase tungsten oxide cocatalysts achieve a highly efficient yield rate of metallic lithium and an excellent faradaic efficiency. This work provides a new strategy for the green extraction of waste lithium and the utilization of solar energy.

Abstract

Photoelectrochemical lithium (Li) extraction can be expected to provide a useful recycle of Li⁺ from waste Li-containing battery, but the process is limited by the photocathodes with poor Li⁺ absorption and low yield rate. Here, we have designed a hierarchical silicon (Si)-based photocathode with mixed-phase tungsten oxide (WO₃) cocatalysts for photoelectrochemical Li extraction under 1 sun illumination, achieving a high Li yield rate of ≈223.0 μg cm⁻² h⁻¹ and an excellent faradaic efficiency of 91.9 % at 0.0817 V versus Li^0/+ redox couple. The WO₃ cocatalysts with the mixture of amorphous and crystalline phase accelerates the Li⁺ insertion and precipitation and enriches the concentration of Li⁺ at the photocathode surface. This robust photoelectrochemical Li extraction system provides a new insight on designing green and efficient route for cyclic utilization of Li resources in the sustainable energy field.

An integrated free-standing functional carbon positive electrode (named MSCG) with a “point-line-plane” hierarchical architecture at the practical level of ultrahigh mass-loading (>50 mg cm^–2) is developed for dual-ion batteries (DIBs). The DIBs with ultrahigh-mass-loading MSCG electrodes achieves a high energy density of 379 Wh kg^–1 based on the mass of electrode materials, which offers a promising strategy for high-energy-density energy-storage devices.

Abstract

Dual-ion batteries (DIBs) have been attracting great attention for the storage of stationary energy due to their low cost, environmental friendliness, and high working voltage. However, most reports on DIBs involve low-mass-loading electrodes (<2.5 mg), while the use of high mass-loading electrodes (>10 mg cm⁻²), which are critical for practical application, is overlooked. Herein, an integrated free-standing functional carbon positive electrode (named MSCG) with a “point-line-plane” hierarchical architecture at the practical level of ultrahigh mass-loading (>50 mg cm⁻²) is developed for high-energy-density DIBs. The rationally designed microstructure and the advanced assembly method that is adopted produce a well-interconnected ion/electron transport channel in the MSCG electrode, which confers rapid ion/electron kinetic properties while maintaining good mechanical properties. Consequently, the DIBs with ultrahigh-mass-loading MSCG electrodes exhibits a high discharge capacity of 100.5 mAh g⁻¹ at 0.5 C (loading mass of 50 mg cm⁻²) and a long-term cycling performance with a capacity retention of 87.7% at 1 C after 500 cycles (loading mass of 23 mg cm⁻²). Moreover, the DIB with the ultrahigh-mass-loading positive electrode achieves a high energy density of 379 Wh kg⁻¹ based on the mass of electrode materials, the highest value recorded to date for any DIBs.

Nature Communications, Published online: 14 April 2023; doi:10.1038/s41467-023-37769-2

Nature, Published online: 12 October 2022; doi:10.1038/s41586-022-05281-0

Nature Communications, Published online: 15 September 2022; doi:10.1038/s41467-022-32810-2

Nature Communications, Published online: 27 April 2022; doi:10.1038/s41467-022-29837-w

Nature Communications, Published online: 16 February 2022; doi:10.1038/s41467-022-28542-y

Nature Nanotechnology, Published online: 04 April 2022; doi:10.1038/s41565-022-01102-7

Nature Materials, Published online: 17 March 2022; doi:10.1038/s41563-022-01209-1

Nature, Published online: 23 February 2022; doi:10.1038/s41586-021-04337-x

Nature Communications, Published online: 10 December 2021; doi:10.1038/s41467-021-27531-x

Circular Bioeconomy

The food–materials–energy nexus is most relevant to the circular bioeconomy and is reviewed in the context of next-generation bioplastics by Caio G. Otoni, Orlando J. Rojas, and co-workers in article number 2102520. The state-of-the-art strategies used to upcycle agri-food losses and wastes (FLW) into multifunctional and advanced materials rely on the deconstruction and reassembly, synthesis, and engineering of FLW-derived monomeric, polymeric, and colloidal building blocks.

Metasufaces

In article number 2102232, Hatice Altug and co-workers demonstrate a wafer-scale nanofabrication method for manufacturing highly efficient meta-optical elements and metasurface-based optofluidic biosensors. The demonstrated method enables low-cost infrared optical components and disposable sensor chips for medical diagnostics, and has the potential to accelerate the early adoption of metasurface technology for commercial applications in the technologically important mid-infrared spectral region.

Efficient tailoring of valley-polarized photoluminescence from monolayer WS₂ at room temperature (RT) through surface plasmon–exciton interactions with plasmonic Archimedes spiral (PAS) nanostructures is achieved in this manuscript. The degree of valley polarization of WS₂–PAS heterostructures at RT can be further enhanced from 40% to 70% by modulating the carrier doping via a backgate field effect transistor (FET) device.

Abstract

Monolayer transition metal dichalcogenides (TMDs) have intrinsic valley degrees of freedom, making them appealing for exploiting valleytronic applications in information storage and processing. WS₂ monolayer possesses two inequivalent valleys in the Brillouin zone, each valley coupling selectively with a circular polarization of light. The degree of valley polarization (DVP) under the excitation of circularly polarized light (CPL) is a parameter that determines the purity of valley polarized photoluminescence (PL) of monolayer WS₂. Here efficient tailoring of valley-polarized PL from monolayer WS₂ at room temperature (RT) through surface plasmon–exciton interactions with plasmonic Archimedes spiral (PAS) nanostructures is reported. The DVP of WS₂ at RT can be enhanced from <5% to 40% and 50% by using 2 turns (2T) and 4 turns (4T) of PAS, respectively. Further enhancement and control of excitonic valley polarization is demonstrated by electrostatically doping monolayer WS₂. For CPL on WS₂–2TPAS heterostructures, the 40% valley polarization is enhanced to 70% by modulating the carrier doping via a backgate, which may be attributed to the screening of momentum-dependent long-range electron–hole exchange interactions. The manifestation of electrically tunable valley-polarized emission from WS₂–PAS heterostructures presents a new strategy toward harnessing valley excitons for application in ultrathin valleytronic devices.

The evaporation of Au or the sputtering of Cr on 2D layered hexagonal boron nitride (h-BN) produces local atomic defects in its structure, specially at its interfaces, which increases the leakage current across it. It is found that the deposition of metal on hexagonal boron nitride (h-BN) using inkjet printing does not introduce any defect, and maintains its layered structure free of defects.

Abstract

2D materials have many outstanding properties that make them attractive for the fabrication of electronic devices, such as high conductivity, flexibility, and transparency. However, integrating 2D materials in commercial devices and circuits is challenging because their structure and properties can be damaged during the fabrication process. Recent studies have demonstrated that standard metal deposition techniques (like electron beam evaporation and sputtering) significantly damage the atomic structure of 2D materials. Here it is shown that the deposition of metal via inkjet printing technology does not produce any observable damage in the atomic structure of ultrathin 2D materials, and it can keep a sharp interface. These conclusions are supported by abundant data obtained via atomistic simulations, transmission electron microscopy, nanochemical metrology, and device characterization in a probe station. The results are important for the understanding of inkjet printing technology applied to 2D materials, and they could contribute to the better design and optimization of electronic devices and circuits.

Nature Communications, Published online: 05 November 2021; doi:10.1038/s41467-021-26678-x