研究组介绍了一种新型范德华(vdW)材料声子色散和电子-声子耦合(EPC)映射技术。出版两步热处理诱导仅尺寸大于10nm的文导闻科Al3Sc纳米析出相表面发生Samson相Al3(Mg,Sc)2的非均相形核。
▲ Abstract:
Nickel is 读新a critical element in the shift to sustainable energy systems, with the demand for nickel projected to exceed 6 million tons annually by 2040, largely driven by the electrification of the transport sector. Primary nickel production uses acids and carbon-based reductants, emitting about 20 tons of carbon dioxide per ton of nickel produced. Here we present a method using fossil-free hydrogen-plasma-based reduction to extract nickel from low-grade ore variants known as laterites. We bypass the traditional multistep process and combine calcination, smelting, reduction and refining into a single metallurgical step conducted in one furnace. This approach produces high-grade ferronickel alloys at fast reduction kinetics. Thermodynamic control of the atmosphere of the furnace enables selective nickel reduction, yielding an alloy with minimal impurities (<0.04 wt% silicon, approximately 0.01 wt% phosphorus and <0.09 wt% calcium), eliminating the need for further refining. The proposed method has the potential to be up to about 18% more energy efficient while cutting direct carbon dioxide emissions by up to 84% compared with current practice. Our work thus shows a sustainable approach to help resolve the contradiction between the beneficial use of nickel in sustainable energy technologies and the environmental harm caused by its production.
地球科学Earth Science
Global emergence of unprecedented lifetime exposure to climate extremes
全球出现了前所未有的极端气候终生暴露
▲ 作者:Luke Grant, Inne Vanderkelen, Lukas Gudmundsson, Erich Fischer, Sonia I. Seneviratne & Wim Thiery
▲链接:
https://www.nature.com/articles/s41586-025-08907-1
▲摘要:
在人为气候变化的影响下,
▲ Abstract:
Metal-halide perovskites are 学网promising light-emitter candidates for next-generation light-emitting diodes (LEDs). Achieving high brightness and efficiency simultaneously in pure-red perovskite LEDs (PeLEDs) is an ongoing goal. Three-dimensional (3D) CsPbI3-xBrx emitters have excellent carrier transport capability and high colour purity, which could allow efficient and ultrabright pure-red PeLEDs. However, such devices are prone to efficiency roll-off, resulting in low efficiency and low brightness under high current density. Here, by using electrically excited transient absorption spectroscopy, we discovered the efficiency roll-off was induced by hole leakage. Therefore, we developed a CsPbI3-xBrx intragrain heterostructure containing narrow bandgap emitters and wide bandgap barriers to confine the injected carriers. The wide bandgap barrier was incorporated by introducing strongly bonding molecules into the [PbX6]4- framework to expand the 3D CsPbI3-xBrx lattice. This strategy resulted in bright and efficient pure-red PeLEDs, with a high brightness of 24,600 cd m-2, maximum external quantum efficiency of 24.2% and low efficiency roll-off, maintaining a 10.5% external quantum efficiency at a high luminance of 22,670 cd m-2.
Structurally complex phase engineering enables hydrogen-tolerant Al alloys
结构复杂的相工程实现抗氢脆铝合金
▲ 作者:Shengyu Jiang, Yuantao Xu, Ruihong Wang, Xinren Chen, Chaoshuai Guan, Yong Peng, et al.
▲链接:
https://www.nature.com/articles/s41586-025-08879-2
▲摘要:
氢脆(HE)降低了铝(Al)合金的耐久性,然而,自然周论这些颗粒通常以较低的出版数量密度形成。发现了由空穴泄漏引起的文导闻科效率骤降。全球变暖路径将比前工业化温度高出2.7℃),读新
▲ Abstract:
The 学网coupling between electrons and phonons is one of the fundamental interactions in solids, underpinning a wide range of phenomena, such as resistivity, heat conductivity and superconductivity. However, direct measurements of this coupling for individual phonon modes remain a substantial challenge. In this work, we introduce a new technique for mapping phonon dispersions and electron–phonon coupling (EPC) in van der Waals (vdW) materials. By generalizing the quantum twisting microscope (QTM) to cryogenic temperatures, we demonstrate its capability to map not only electronic dispersions through elastic momentum-conserving tunnelling but also phononic dispersions through inelastic momentum-conserving tunnelling. Crucially, the inelastic tunnelling strength provides a direct and quantitative measure of the momentum and mode-resolved EPC. We use this technique to measure the phonon spectrum and EPC of twisted bilayer graphene (TBG) with twist angles larger than 6°. Notably, we find that, unlike standard acoustic phonons, whose coupling to electrons diminishes as their momentum tends to zero, TBG exhibits a low-energy mode whose coupling increases with decreasing twist angle. We show that this unusual coupling arises from the modulation of the interlayer tunnelling by a layer-antisymmetric ‘phason’ mode of the moiré system. The technique demonstrated here opens the way for examining a large variety of other neutral collective modes that couple to electronic tunnelling, including plasmons, magnons and spinons in quantum materials.
材料科学Material Science
Intragrain 3D perovskite heterostructure for high-performance pure-red perovskite LEDs
晶间三维钙钛矿异质结构助力高性能纯红色钙钛矿LED
▲ 作者:Yong-Hui Song, Bo Li, Zi-Jian Wang, Xiao-Lin Tai, Guan-Jie Ding, Zi-Du Li, et al.
▲链接:
https://www.nature.com/articles/s41586-025-08867-6
▲摘要:
金属卤化物钙钛矿是下一代发光二极管(LED)颇有前景的发光候选材料。具有24600 cd m-2的自然周论高亮度,其定义了LAB的出版最上部,镍的文导闻科年需求量预计将超过600万吨,证明了QTM不仅可以通过弹性动量守恒隧穿来映射电子色散,读新
在社会经济脆弱性高的学网人群中,
研究组提出了一种使用无化石氢等离子体还原的方法,河流洪水的比例将上升至14%。岩石圈-软流圈边界(LAB)充当了一个渗透屏障,该研究结果呼吁大幅、须保留本网站注明的“来源”,热导性和超导性等广泛现象。然而,同时直接二氧化碳排放减少高达84%。导致在高电流密度下效率低、不同于与电子耦合随着其动量趋于零而减弱的标准声频声子,
研究组展示了位于Juan de Fuca洋脊和Cobb-Eickelberg热点交汇处的轴向火山下延伸至地壳深处(5~6千米)的LAB三维地震反射图像。但地壳深处LAB的性质仍不确定,
在升温1.5℃的路径下,以及极低的效率骤降,
该策略产生了明亮高效的纯红色PeLED,控制了喷发和热液循环以及喷发熔岩的化学成分。
▲ Abstract:
Climate extremes are escalating under anthropogenic climate change. Yet, how this translates into unprecedented cumulative extreme event exposure in a person’s lifetime remains unclear. Here we use climate models, impact models and demographic data to project the number of people experiencing cumulative lifetime exposure to climate extremes above the 99.99th percentile of exposure expected in a pre-industrial climate. We project that the birth cohort fraction facing this unprecedented lifetime exposure to heatwaves, crop failures, river floods, droughts, wildfires and tropical cyclones will at least double from 1960 to 2020 under current mitigation policies aligned with a global warming pathway reaching 2.7 °C above pre-industrial temperatures by 2100. Under a 1.5 ℃ pathway, 52% of people born in 2020 will experience unprecedented lifetime exposure to heatwaves. If global warming reaches 3.5 °C by 2100, this fraction rises to 92% for heatwaves, 29% for crop failures and 14% for river floods. The chance of facing unprecedented lifetime exposure to heatwaves is substantially larger among population groups characterized by high socioeconomic vulnerabilities. Our results call for deep and sustained greenhouse gas emissions reductions to lower the burden of climate change on current young generations.
Melt focusing along lithosphere–asthenosphere boundary below Axial volcano
沿轴向火山下方岩石圈-软流圈边界的熔体聚集
▲ 作者:G. M. Kent, A. F. Arnulf, S. C. Singh, H. Carton, A. J. Harding & S. Saustrup
▲链接:
https://www.nature.com/articles/s41586-025-08865-8
▲摘要:
在海洋扩张中心之下,TBG呈现出低能模式,抗HE性能提高了近5倍,将煅烧、
因此,将热点相关和中大洋扩张中心相关的岩浆活动聚集在火山中心,得到杂质最少的合金(硅含量<0.04 wt%,至关重要的是,还原和精炼整合到一座熔炉内的单一冶金步骤中。且易于适应大规模的工业生产。根据目前的缓解政策(即到2100年,即一个熔体驻留的区域(取代了单一“岩浆储层”的概念)。
▲ Abstract:
Hydrogen embrittlement (HE) impairs the durability of aluminium (Al) alloys and hinders their use in a hydrogen economy. Intermetallic compound particles in Al alloys can trap hydrogen and mitigate HE, but these particles usually form in a low number density compared with conventional strengthening nanoprecipitates. Here we report a size-sieved complex precipitation in Sc-added Al–Mg alloys to achieve a high-density dispersion of both fine Al3Sc nanoprecipitates and in situ formed core-shell Al3(Mg,Sc)2/Al3Sc nanophases with high hydrogen-trapping ability. The two-step heat treatment induces heterogeneous nucleation of the Samson-phase Al3(Mg,Sc)2 on the surface of Al3Sc nanoprecipitates that are only above 10nm in size. The size dependence is associated with Al3Sc nanoprecipitate incoherency, which leads to local segregation of magnesium and triggers the formation of Al3(Mg,Sc)2. The tailored distribution of dual nanoprecipitates in our Al–Mg–Sc alloy provides about a 40% increase in strength and nearly five times improved HE resistance compared with the Sc-free alloy, reaching a record tensile uniform elongation in Al alloys charged with H up to 7ppmw. We apply this strategy to other Al–Mg-based alloys, such as Al–Mg–Ti–Zr, Al–Mg–Cu–Sc and Al–Mg–Zn–Sc alloys. Our work showcases a possible route to increase hydrogen resistance in high-strength Al alloys and could be readily adapted to large-scale industrial production.
化学Chemistry
Sustainable nickel enabled by hydrogen-based reduction
氢基还原实现可持续镍生产
▲ 作者:U. Manzoor, L. Mujica Roncery, D. Raabe & I. R. Souza Filho
▲链接:
https://www.nature.com/articles/s41586-025-08901-7
▲摘要:
镍是向可持续能源系统转变的关键因素。极端气候正在升级。热控制的岩浆同化可能沿该表面发生。并不意味着代表本网站观点或证实其内容的真实性;如其他媒体、从1960年到2020年的出生队列中,持续减少温室气体排放,
尺寸依赖性与Al3Sc纳米析出相的非共格性有关,他们预计,他们避开了传统的多步骤工艺,这表明在其他火山系统(如冰岛)中,该技术为研究与电子隧穿耦合的大量其他中性集体模式开辟了道路,农作物歉收的比例将上升至29%,面临前所未有终生热浪的概率要大得多。
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