Size and Orientation Effects on the Kinetics and Structure of Nickelide Contacts to InGaAs Fin Structures

The rapid development of ultrascaled III–V compound semiconductor devices urges the detailed investigation of metal–semiconductor contacts at nanoscale where crystal orientation, size, and structural phase play dominant roles in device performance. Here, we report the first study on the solid-state reaction between metal (Ni) and ternary III–V semiconductor (In_0.53Ga_0.47As) nanochannels to reveal the reaction kinetics, formed crystal structure, and interfacial properties. We observe a size-dependent Ni surface diffusion dominant kinetic process that gradually departs to a volume diffusion process as the Fin width increases, as properly depicted with our Fin-specific growth model. The interfacial relationship was found to be Ni₄InGaAs₂ (0001) ∥ In_0.53Ga_0.47As (111) with a single Ni₄InGaAs₂ phase whose [0001] axis exhibit a peculiar rotation away from the nickelide/InGaAs interface due to surface energy minimization. This crystalline interfacial relationship is responsible for introducing a uniaxial height expansion of 33% ± 5% in the formed nickelide segments. Further, the nickelide formation resulted in both in-plane and out-of-plane compressive strains in the Fin channels, significantly altering the In_0.53Ga_0.47As energy band-edge structure near the interface with a peak bandgap energy of ∼1.26 eV. These timely observations advance our understanding and development for self-aligned contacts to III–V nanochannels and for engineering new processes that can maximize their device performance

Melamine-Regulated Ceramic/Polymer Electrolyte Interface Promotes High Stability in Lithium-Metal Battery

With the advantages of organic and inorganic solid electrolytes, composite electrolytes are a promising option for use in all-solid-state Li-metal batteries. However, the considerable disparity in interfacial energy between ceramic and polymer electrolytes results in poor solid–solid contacts and the internal creation of a space charge layer in the composite electrolyte. Here, we report a melamine (MA) transition layer for the sake of strengthening the bond between Li1.5Al0.5Ge1.5(PO4)3 (LAGP) and poly(ethylene oxide) (PEO) to enhance physical and electrochemical properties. The MA is absorbed on LAGP by electron transfer from LAGP to MA’s triazine ring, resulting in intimate contact and good mechanical stability. Simultaneously, the MA stabilizes the Li-salt anion, reduces its decomposition reactions at the interface between PEO and LAGP in the electrolyte, and promotes free Li+ dissociation, resulting in superior ionic conductivity and interfacial stability. Thus, the solid electrolyte film enables symmetric Li/Li batteries to achieve steady Li plating/stripping for more than 1300 h at a current density of 0.25 mA cm–2. The all-solid-state Li|PEO–MA@LAGP|LFP cell exhibits improved cycling stability. The Li/PEO–MA@LAGP/NCM523 cell shows a cycling life that is a factor of 5 times greater than that of a cell based on PEO–LAGP

ZnO/Pd@ZIF-7-Based Gas Sensors for Selective Methane Sensing

Selective methane detection is essential for process safety in industries such as coal mining, where CO, NH3, and NO2 serve as interfering gases. A promising approach is to use metal oxide semiconductor (MOS)-based sensors, which are low-cost, highly sensitive, and easy to fabricate. However, the poor selectivity of MOS sensors due to nonselective surface reactions remains a significant challenge. In this study, we fabricated a ZnO/Pd@ZIF-7 core-shell structure–based gas sensor using a self-sacrificial method. The ZnO/Pd layer served as the sensitive layer to generate sensing signals, while the ZIF-7 shell acted as a filter. By manipulating gas diffusion, ZIF-7 significantly improved CH4 sensing selectivity against CO, NH3, and NO2. For NO2, which strongly interacts with ZIF-7, the diffusion through ZIF-7 was significantly hindered, resulting in a decreased response across all temperature ranges (110–250 °C). For CH4, CO, and NH3, which weakly interact with ZIF-7, the influence of ZIF-7 depended on temperature, as competition occurred between surface reactions and diffusion through ZIF-7. At low temperatures, ZIF-7 enriched gases and promoted the response of the three gases. At elevated temperatures, ZIF-7 separated gases according to their molecular polarity, where the diffusion of polar CO and NH3 was more hindered than nonpolar CH4. The excellent CH4 selectivity against CO, NH3, and NO2 was achieved at 210 °C, with fast response/recovery, good repeatability, and long-term stability. Our study not only provides a possible solution to enable sensing selectivity of MOS to CH4, but the insights into the effect of the ZIF-7 filter may also inspire the development of highly selective gas sensors

Multielement Co-Doped Carbon Derived from Spent LIBs Boosts Potassium Storage

Sustainability issues with batteries include making sure that the materials can be recycled into electrodes once they are no longer needed and that they have enough power to charge all devices. Existing technologies for material recovery and selective extraction continue to be inefficient and unsustainable. Here, N/S co-doping porous carbon materials comprising transitional-metal nanoparticles are synthesized through microstructural reconstruction from the waste layered cathode materials. The resultant three-dimensional (3D) porous carbon materials have various distinct and desirable structural characteristics and function admirably in potassium-ion batteries. The internal particle distribution, the interconnected carbon layer network, and the open-packed structure of microcapsules all contribute to the electrochemical transfer process. The proposed strategy offers almost zero-emission and pollution-free environment and can be extended to various spent lithium-ion batteries (LIBs) containing Li, Ni, Co, Mn, and other metals. The research may provide the potential to extend the environmental frontier for the development of energy materials

Decarbonylative Coupling of α‑Keto Acids and Ynamides for Synthesis of β‑Keto Imides

A novel decarbonylative coupling of α-keto acids and ynamides with extrusion of CO for synthesis of β-keto imides is reported. This process features mild reaction conditions, a broad substrate scope, and high efficiency. An isotope-labeling reaction and GC analysis were conducted to elucidate a plausible reaction mechanism

Additional file 1 of Association between light at night and the risk of child death in sub-saharan Africa: a cross-sectional analysis based on DHS data

Supplementary Material 1: Figure S1. Flow diagram of the country selection progress in the analysis. Figure S2. Distribution of LAN in Africa in 2005. Figure S3. Changes in annual mean LAN in the 15 countries included in this study from 2005 to 2013. Figure S4. Correlation between household wealth quantile and LAN in the 15 countries included in this study. Table S1. Distribution of Under 5 mortality rate and LAN level for the study population in urban and rural areas in 15 African countries. Table S2. Stratified analysis of LAN and risk of child mortality in Afric

Air Pollution and Cardiac Arrest: A More Significant Intermediate Role of COPD than Cardiac Events

No prior studies have linked long-term air pollution exposure to incident sudden cardiac arrest (SCA) or its possible development trajectories. We aimed to investigate the association between long-term exposure to air pollution and SCA, as well as possible intermediate diseases. Based on the UK Biobank cohort, Cox proportional hazard model was applied to explore associations between air pollutants and SCA. Chronic obstructive pulmonary disease (COPD) and major adverse cardiovascular events (MACE) were selected as intermediate conditions, and multistate model was fitted for trajectory analysis. During a median follow-up of 13.7 years, 2884 participants developed SCA among 458 237 individuals. The hazard ratios (HRs) for SCA were 1.04–1.12 per interquartile range increment in concentrations of fine particulate matter, inhalable particulate matter, nitrogen dioxide, and nitrogen oxides. Most prominently, air pollutants could induce SCA through promoting transitions from baseline health to COPD (HRs: 1.06–1.24) and then to SCA (HRs: 1.16–1.27). Less importantly, SCA could be developed through transitions from baseline health to MACE (HRs: 1.02–1.07) and further to SCA (HRs: 1.12–1.16). This study provides novel and compelling evidence that long-term exposure to air pollution could promote the development of SCA, with COPD serving as a more important intermediate condition than MACE

Sustainable Recycling and Regeneration of Cathode Scraps from Industrial Production of Lithium-Ion Batteries

The burst demand of lithium-ion batteries (LIBs) for energy storage leads to an increasing production of LIBs. The huge amount of electrode scraps produced during the industrial production cannot be overlooked. A sustainable and simple method was developed to regenerate Li­(Ni1/3Co1/3Mn1/3)­O2 electrode scraps as new cathodes for LIBs. Three different separation processes, including direct calcination, solvent dissolution, and basic solution dissolution, were applied to obtain the active materials. Then, a heat treatment was used to regenerate the scraps. The effects of separation methods and heat treatment temperatures were systematically investigated. The results show that the scraps regenerated with solvent dissolution and heat treatment at 800 °C deliver the highest reversible discharge capacities of 150.2 mA h g–1 at 0.2C after 100 cycles with capacity retention of 95.1%, which is comparable with commercial Li­(Ni1/3Co1/3Mn1/3)­O2 cathodes. When cycled at 1C, a highly reversible discharge capacity of 128.1 mA h g–1 can be obtained after 200 cycles. By contrast, scraps regenerated through a direct calcination method at 600 °C exhibit the best cycling performances, with the highest capacity retention of 96.7% after 100 cycles at 0.2C and 90.5% after 200 cycles at 1C. By characterizations of XRD, SEM, XPS, and particle size distribution analysis, the improved electrochemical performances of regenerated cathodes can be attributed to the uniform particle morphology and newly formed protective LiF composite. The simple and green regeneration process provides a novel perspective of recycling scraps from industrial production of LIBs

Additional file 1 of Mechanistic insights into the health benefits of fish-oil supplementation against fine particulate matter air pollution: a randomized controlled trial

Supplementary Material