As the global demand for flexible and efficient energy storage systems increases quickly, there's an urgent need to develop innovative approaches to significantly enhance their performance, especially under extreme temperature conditions. To address this challenge, we hereby propose a scalable strategy that involves preparing high-performance MXene@GO/CMC films via roll-to-roll assisted doctor blade coating integrated with sequential bridging techniques, and subsequently employing ion-bridging to stabilize their oriented structure. The film exhibit an outstanding photothermal conversion efficiency of 90.1% at 100 mW/cm2, with simulations corroborating the temperature distribution. When integrated into an asymmetric flexible supercapacitor (SC), the device delivers a 48.0% increase in capacitance at a scan rate of 20 mV/s at -40 °C, retaining 73.3% of its room-temperature performance. At -40 °C, energy density increases by 87.1% under 140 mW/cm2 illumination. In addition, the capacitance retention after 1000 cycles improved from 85.5% (without light) to 92.2% (with light). This design for photothermal flexible energy storage devices offers a promising pathway for developing sustainable and efficient energy storage solutions.

Sodium-ion batteries (SIBs) are promising for large-scale energy storage, with cathode materials being key to their electrochemical performance. Recently, Na3Fe2(PO4)P2O7 has drawn attention as a potential cathode material for SIBs due to its low cost and stable crystal structure. In this study, we prepared a porous Na3Fe2(PO4) P2O7 (NFPP) and introduced nano-BaTiO3 (BT) to create a composite cathode. The synthesized Na3Fe2(PO4) P2O7-3 %BaTiO3 (NFPP-3BT) delivered a reversible capacity of 62.7 mAh g- 1 at an ultra-high rate of 120C and exhibited a long cycle life of 2000 cycles at 10C with a capacity retention of 80.5 %. The high-rate performance is attributed to the synergic effect of the porous structure of NFPP and the polarization electric field from BT's ferroelectricity, enhancing the Na+ diffusion. Moreover, the strong adsorption energy for sodium salt anions on the BT surface accelerates the desolvation process and improves the stability of cathode electrolyte interphase (CEI), further improving the rate and cycling performance of NFPP. This work unveils a new strategy for achieving both high-rate capability and excellent cycle stability in SIBs through the synergistic effect of mixed polyanionic cathode materials and ferroelectric materials.

As the size of state-of-the-art copper interconnects shrinks to the nanoscale, carrier scattering greatly increases their resistance, causing signal delay and reliability issues. Alternative conductors are therefore needed to sustain interconnect scaling beyond conventional charge-transport mechanisms. Here we demonstrate CoSi semimetal for highly scalable, conductive and reliable interconnects. As the CoSi thickness decreases from 1 µm to ∼20 nm, its resistivity decreases from 7.0 to 0.72 μΩ·cm due to the highly conductive surface path. The room-temperature resistivity of 20-nm-thick CoSi is one-tenth that of copper at the same thickness. The high cohesive energy (5.4 eV) and migration barrier (3.7 eV) of CoSi confer excellent reliability at current densities of up to 108 A cm-2 and temperatures up to 450 °C. Radiofrequency measurements demonstrate CoSi interconnect operation at frequencies up to 40 GHz. We further integrate a CoSi interconnect with a 16-nm-node silicon ring oscillator, which operates at the same frequency as its metal-interconnected counterpart.

Cu-based catalysts are extensively employed in dimethyl oxalate (DMO) hydrogenation, but it is rather challenging to obtain methyl glycolate (MG) over traditional Cu-based catalysts with high selectivity at high DMO conversion. Herein, the physicochemical properties of the typical Cu/SiO2 catalyst and its corresponding catalytic performance toward DMO hydrogenation were tuned by surface modification with a biological template (histidine). On the premise of near-total conversion of DMO, the MG selectivity substantially increased from 15.7 % to 82.9 % when the typical Cu/SiO2 catalyst was modified by 7 wt% histidine, which was fairly impressive among the reported results up to now. Furthermore, comprehensive characterization and kinetic study disclosed the underlying mechanism. After thermal treatment, histidine retains its skeleton framework (imidazole), the emerging Cu-N interaction weakened the Cu-silica interaction, leading to the reduction in percentage of Cu+ and increase in electron density on the Cu/SiO2 catalyst. As a result, the adsorption and activation ability toward MG were obviously suppressed, which was proved as the critical step for selective hydrogenation of DMO toward MG.

2D layered embedding materials have shown promising applications in rapidly rechargeable sodium-ion batteries (SIBs). However, the most commonly used embedding structures are susceptible to damage and collapse with increasing cycles, which in turn leads to a degradation of the overall performance of the batteries. In order to address this issue, a "stress-strain transition" mechanism is proposed to form a heterostructure by introducing pyramid-like MnSe into the MoS2 lattice to reduce the irreversible reconstruction under deep discharge. Density functional theory and Finite element method simulation reveal that the strong orbital coupling of Mn-Mo at the heterogeneous interface provides a guarantee for the directional migration of ions, alleviates the lattice expansion caused by embedding strain, and avoids irreversible structural changes during battery operation. The capacity measured at 0.1C is 612 mAh g-1, which is consistent with the theoretical prediction. The experimental results demonstrate that the capacity is maintained at 80.3% of the initial value after 3500 cycles. This work demonstrates a strategy of addressing the structural collapse of 2D layered materials and paves the way for the commercialization of SIBs.

The effective separation of ethyl tert-butyl ether (ETBE) and ethanol (EtOH) azeotropes during the production of gasoline additive ETBE has far-reaching significance for resource recovery and sustainable development. This work first proposed using green and sustainable deep eutectic solvents (DESs) to separate ETBE-EtOH efficiently. As an analog of ionic liquids, DESs are environmentally friendly, low-cost, and biodegradable. Based on a method combining quantum chemical calculation, molecular dynamics simulation, and toxicity analysis, the separation performance and mechanism of candidate DESs were explored, and DESs with better separation effects were preliminarily screened out. Using an improved Rose vapor-liquid equilibrium (VLE) reactor, a VLE experiment was carried out on the screened entrainers and the EtOH and ETBE azeotropic system. The experimental results showed that the prepared choline chloride-propylene glycol can achieve better azeotropic separation. This study provides theoretical guidance for the solvent screening of DESs in the extractive distillation separation by combining molecular simulation with experiments.

Ru-based catalysts are considered highly promising candidates for enabling cost-effective proton exchange membrane water electrolyzers (PEMWEs). However, under the harsh conditions of acidic oxygen evolution reaction (OER), Ru sites are prone to undesired overoxidation, leading to substantial deterioration in catalytic activity. Herein, we demonstrate a hydrogen-bond-mediated mechanism triggered by fluoride ion (F-) in RuO2 (RuO1.86F0.14) to achieve both high activity and stability. The spontaneous transfer of protons to bridging oxygen through hydrogen bonds accelerates the deprotonation of an oxo-intermediate, which improves the kinetics of the OER in acidic conditions. Moreover, the highly electronegative F- diminishes the covalency of Ru-O bonds and thus boosts the stability of RuO2. The optimized RuO1.86F0.14 catalyst presents an ultralow overpotential of 153 mV at 10 mA cm-2 and can sustain for more than 980 h with a low degradation rate of 27 μV h-1. Notably, the RuO1.86F0.14 applied in PEMWEs requires only 1.63 V and maintains stable operation for over 100 h at 1 A cm-2. This work demonstrates a promising anion-modulated approach to the design of high-performance acidic OER catalysts.

Zinc-ion hybrid supercapacitors (ZIHSCs) are emerging as a promising energy storage device, combining the benefits of traditional batteries and capacitors, including high energy density, incredible power density, a wide voltage window, and excellent capacity retention. In this study, a Cu2+ and Zn2+ co-doped needle-like tunnel- structured alpha-MnO2material is proposed as the cathode (Cu-Zn-MnO2@CC), which is grown on an acid-treated flexible carbon cloth substrate using a simple hydrothermal synthesis method. Along with an anode made of super-mesoporous activated carbon derived from waste rice husks (ACrh@CC). The synergistic effect of the co- doping stabilizes the nanowire tunnel structure and provides more active sites. As a result, the Cu-ZnMnO2@CC//2 M ZnSO4//ACrh@CC ZIHSC achieves an ultrahigh specific capacitance of 1241.85 mF cm-2 at 1 mA cm-2, representing an improvement of more than 50 % in performance compared to with conventional MnO2@CC ZIHSC. And a maximum areal energy density of 689.9 mu Wh cm-2 at a power density of 1 mW cm-2. After 20,000 cycles, it retains 86.35 % of its initial capacitance. Furthermore, the assembled flexible device achieves a specific capacitance of 1070.21 mF cm-2 at 1 mA cm-2. This device can provide long-term power for electronic devices such as digital watches and timers. The study offers crucial understanding regarding structure of ZIHSC electrode materials and opens up possibilities for their potential applications.

The growing market for sodium-ion batteries has stimulated interest in research on Prussian blue-type cathode materials. Iron hexacyanoferrate (FeHCF) is considered a desirable Prussian blue-type cathode, but the incomplete electrochemical property of its low-spin iron sites hinders its further practical application. In this paper, carboxymethyl cellulose is demonstrated to have an appropriate binding energy through DFT calculations, synthesize Prussian blue in situ, balance Fe3+ and water in FeHCF, and introduce FeIII vacancies to activate low-spin Fe sites. Thus, at a 1 C rate, it achieves an initial discharge capacity of 154.7 mAh g-1 with an energy density of 470.8 Wh kg-1. The capacity retention is 70.2% after 4000 cycles at a rate of 100 C. This work provides a simpler way to develop more cost-effective, faster, and more durable cathode materials for sodium-ion energy storage.

While transition-metal oxides have emerged as promising candidates for lithium energy storage, several issues are remained to be addressed such as low conductivity, rate performance, and recyclability. In this study, a threedimensional interconnected sheet-like heterostructure of WO3-x coated with reduced graphene oxide (rGO) was synthesized using the hydrothermal method. This structure significantly enhanced the conductivity of WO3-x. By combining the heterojunction with oxygen vacancies (OV), the active sites are enlarged, promoting the effective movement of ions and electrons at the interface between the WO3-x and rGO. The prepared anode exhibits a high specific capacity of 1202.6 mAh/g at 0.1 A g-1, with a cycling retention rate of 96 % after 100 cycles. Meanwhile, even at 5 A g- 1, it still maintains a capacity of 305 mAh/g after 500 cycles. Theoretical calculations reveal that the presence of the composite heterogeneous structure enables WO3-x@rGO to possess appropriate adsorption energy, lower work function, and reduced barriers. This arrangement provides abundant active sites, promoting the rapid penetration of the electrolyte and enhancing the interface reaction kinetics, which is consistent with the experimental results. This study offers a new strategy for Li-ion anode materials.

Zinc-ion hybrid capacitors (ZIHCs) are expected to become the next generation of energy storage devices, highly anticipated for their battery-like performance and lower cost. However, because of their unmanageable structural deformation and inadequate cycling capabilities, they face significant difficulties and challenges in practical production and applications. In this paper, we developed and assembled a flexible solid-state zinc ion hybrid capacitor, which utilizes a gel electrolyte, activated carbon (AC) as the anode, and porous Fe3+ doped MnO2 (Fe-MnO2) as the cathode. The embedding of Fe3+ in MnO2 broadens the original ion channels and provides more electrochemically active sites. The gel electrolyte is formed with poly(vinyl alcohol) (PVA) providing a flexible framework, carboxymethylcellulose (CMC) offering rigid support, and enhanced low-temperature performance due to the addition of ethylene glycol (EG). This combination results in excellent mechanical properties and high ionic conductivity, ensuring stability even under low-temperature conditions. As a result, the flexible ZIHC showcases exceptional specific capacitance, achieving a capacitance of 848.8 mF cm-2 at a current density of 2 mA cm-2, and strong stability when subjected to bending tests. Notably, even under low-temperature conditions of -20 degrees C, the device maintains consistent electrochemical performance, with a remarkable cycle retention rate of 93.75% after 15 000 cycles. This study demonstrates significant advancements in energy storage systems, creating opportunities for the use of flexible devices across a range of applications.

Low temperature has been a major challenge for lithium-ion batteries (LIBs) to maintain satisfied electrochemical performance, and the main reason is the deactivation of electrolyte with the decreasing temperature. To address this point, in present work, we develop a low-temperature resistant electrolyte which includes ethyl acetate (EA) and fluoroethylene carbonate (FEC) as solvent and lithium difluoro(oxalato)borate (LiDFOB) as the primary lithium salt. Due to the preferential decomposition of LiDFOB and FEC, a solid electrolyte interface rich in LiF is formed on the lithium metal anodes (LMAs) and lithium cobalt oxide (LCO) cathodes, contributing to higher stability and rapid desolvation of Li+ ions. The batteries with the optimized electrolyte can undergo cycling tests at -40 degrees C, with a capacity retention of 83.9 % after 200 cycles. Furthermore, the optimized electrolyte exhibits excellent compatibility with both LCO cathodes and graphite (Gr) anodes, enabling a Gr/LCO battery to maintain a capacity retention of 90.3 % after multiple cycles at -25 degrees C. This work proposes a cost-effective electrolyte that can activate potential LIBs in practical scenarios, especially in low-temperature environments. The introduction of moderate concentrations of LiDFOB and FEC has established a solid electrolyte interface rich in LiF. This effectively suppresses side reactions between the electrolyte and lithium metal and promotes the desolvation process of Li+. Li/LCO batteries using this electrolyte exhibit excellent long-term cycling performance even at -40 degrees C. image

： This study explores the use of atomic layer deposition(ALD) technology for encapsulating and modifying the surface of K 2 SiF 6 ∶Mn 4+ (KSFM) red phosphors for white light emitting diodes (LEDs)， and its impact on the struc• tural properties， luminescent characteristics， and stability in a humid and hot environment.The findings reveal that by employing ALD technology with trimethylaluminum as the precursor and ozone as the oxidant， an alumina coating can be formed on the surface of KSFM.X•ray diffraction and surface morphology analyses indicate that the ALD treat• ment process does not affect the crystal phase and morphology of the KSFM phosphors.Moreover， luminescence spectroscopy analysis demonstrates that the alumina coating， owing to its passivation properties， can enhance the lu• minescent intensity of KSFM phosphors without altering their emission wavelength.Furthermore， compared to un• coated KSFM phosphors， the coating layer can significantly enhance the damp•heat stability of KSFM powders.Fol• lowing a 24•hour aging treatment in an 85% humidity/85 ℃ environment， samples coated with ALD maintain 84% of their initial luminescent intensity.Key words： K 2 SiF 6 ∶Mn 4+ ； red phosphor； surface modification； atomic layer deposition； damp•heat stability

Promotional effects of oxygen vacancies of spinel catalysts in CO2 hydrogenation are reported in early works, but the mechanistic origins remain elusive. Here, CoAl2O4 spinels with varying numbers of oxygen vacancies are deliberately designed by a sol-gel method and different post-treatments. By combining catalytic testing, advanced electron microscopic and spectroscopic characterizations, and computational studies, the unusual oxygen vacancy-dependent catalytic behaviors are rationalized. Our work reveals that i) perfect spinel crystals possessing least oxygen vacancies can effectively constrain the Co2+ species at working conditions that are less active but selective to CO; and ii) vacancy-rich spinels promote both H-2 and CO2 activations and COOH* formation, explaining the higher hydrogenation activity, but overwhelming vacancies cause Co2+ reduction and promote direct CO2 * dissociation to CO* and deep hydrogenation to CH4. These molecular-level understandings reinforce the idea of proper design of oxygen vacancies to achieve activity-selectivity balance.

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Due to limited mass loading, high-capacity electrode materials such as transition metal oxides (TMOs) are essential for microscale Li-ion batteries (LIBs) integrated in nano-/micro-electromechanical systems (N/MEMS). Unfortunately, their electrochemical performances are largely plagued by severe mechanical degradation and slow electron transport. Therefore, it is crucial to develop strategies that can improve the structural stability and electronic conductivity of TMO electrodes. In this work, double-carbon (carbon nanotubes and ketjen black) microsphere (DCMS) supported Co3O4 electrodes are fabricated simply through a spray drying and solvothermal method, which are designed to have a mesoporous three-dimensional (3D) hierarchical heterostructure containing well-dispersed Co3O4 nanoparticles within the DCMS framework. An in situ transmission electron microscopy (TEM) study reveals that the DCMS framework can not only provide facile strain accommodation, but also good electronic conductivity, leading to a much improved Li-storage performance compared to other Co3O4-based anodes. The hierarchical electrode exhibits maximum charge capacities of 1205.2 and 678.1 mA h g(-1) at current densities of 0.1 and 2 A g(-1), respectively, as well as a capacity retention of 92.2% at 0.3 A g(-1) after 100 cycles. This study provides a low-cost, simple and general method for developing advanced high-capacity electrodes.

Lanthanide nanoparticles (NPs), which are known as upconversion fluorescence probes for multimodal bioimaging, including magnetic resonance imaging (MRI), have attracted much attentions. In MRI, conventional contrast agents are generally employed separately in a single type of MRI. T1- and T2-weighted MRI alone have unique limitations; therefore, it is urgently necessary to combine the two modalities so as to be able to provide more comprehensive and synergistic diagnostic information than the single modality of MRI. Unfortunately, there is a lack of advanced materials as enhancing agents which are fully suitable for bimodal MRI. Here, we report a new class of hybrid lanthanide nanoparticles as synergistic contrast agents in T1/T2 dual-weighted MRI and imaging-directed tumor diagnosis. The r2/r1 value of BaGdF5 NPs can be readily adjusted from 2.8 to 334.8 by doping with 0%, 50%, or 100% Ln3+ (Ln3+ = Yb3+, Er3+, or Dy3+), respectively. Among these, BaGdF5:50% Er3+ NPs were successfully used as binary contrast agents for T1/T2 dual-weighted MRI and synergistic tumor diagnosis in vivo. These findings reveal that the longitudinal and transverse relaxivities of these Gd3+-based NPs can be controlled by tuning the Ln3+ dopants and their concentrations, providing a simple and general method for designing simultaneous T1/T2 enhancing agents.

Correction for 'Hybrid lanthanide nanoparticles as a new class of binary contrast agents for in vivo T-1/T-2 dual-weighted MRI and synergistic tumor diagnosis' by Zhigao Yi et al., J. Mater. Chem. B, 2016, 4, 2715-2722, https://doi.org/10.1039/C5TB02375K.