国产 av 《天然》（20250403出书）一周论文导读

编译|冯维维国产 av

Nature， 3 April 2025， Volume 640 Issue 8057

《天然》，2025年4月3日，第640卷，8057期

物理学Physics

Downscaling micro- and nano-perovskite LEDs

国内自拍2019在线

中国科学家研发寰宇最小尺寸LED

▲ 作家：Yaxiao Lian， Yaxin Wang， Yucai Yuan， Zhixiang Ren， Weidong Tang， Zhe Liu， Shiyu Xing， Kangyu Ji， Bo Yuan， Yichen Yang， Yuxiang Gao， Shiang Zhang， Ke Zhou， Gan Zhang， Samuel D. Stranks， Baodan Zhao & Dawei Di

▲ 集会：https://www.nature.com/articles/s41586-025-08685-w

▲ 摘录：电子学和光子学的许多时刻打破皆是通过消弱尺寸——使基本开采尺寸更小的经由——竣事的。基于Ⅲ-V半导体的发光二极管（LED）的微型化导致了微型LED，这是知道器的“终极时刻”。但是，微型LED的出产老本很高，当像素尺寸减小到10μm或更小时，它们会阐扬出严重的效果死亡，限制了它们在生意应用中的后劲。

接头者展示了一种基于钙钛矿半导体的新式LED的消弱尺寸的模子，使其低于传统的尺寸限制。通过局部构兵制造有规划，不错细心像素规模的非放射死亡，展示了具少见百微米至约90纳米特征像素长度的微米和纳米钙钛矿LED 。对于近红外（NIR）和绿色微型PeLED，在宽像素长度范围内，平均外部量子效果（EQEs）保抓在20%把握，在消弱尺寸时阐扬出最小的性能镌汰。

该纳米PeLED的特征像素长度低至约90纳米，是刻下报说念的最小的LED，在统统类别的LED阵列中竣事了127000像素/英寸（PPI）的创记录高像素密度。他们的演示展示了微型和纳米PeLED算作下一代光源时刻的上风，具有前所未有的紧凑性和可膨大性。

▲ Abstract：Many technological breakthroughs in electronics and photonics were made possible by downscaling—the process of making elementary devices smaller in size. The downsizing of light-emitting diodes (LEDs) based on Ⅲ–V semiconductors led to micro-LEDs， an ‘ultimate technology’ for displays. However， micro-LEDs are costly to produce and they exhibit severe efficiency losses when the pixel sizes are reduced to about 10 μm or less， hindering their potential in commercial applications. Here we show the downscaling of an emerging class of LEDs based on perovskite semiconductors to below the conventional size limits. Micro- and nano-perovskite LEDs (micro-PeLEDs/nano-PeLEDs) with characteristic pixel lengths from hundreds of micrometres down to about 90 nm are demonstrated， through a localized contact fabrication scheme that prevents non-radiative losses at the pixel boundaries. For our near-infrared (NIR) and green micro-PeLEDs， average external quantum efficiencies (EQEs) are maintained at around 20% across a wide range of pixel lengths (650 to 3.5 μm)， exhibiting minimum performance reduction on downsizing. Our nano-PeLEDs with characteristic pixel lengths down to about 90 nm represent the smallest LEDs reported， enabling a record-high pixel density of 127，000 pixels per inch (PPI) among all classes of LED arrays. Our demonstration showcases the strength of micro- and nano-PeLEDs as a next-generation light-source technology with unprecedented compactness and scalability.

Microsatellite-based real-time quantum key distribution

基于微卫星的及时量子密钥分发

▲ 作家：Yang Li， Wen-Qi Cai， Ji-Gang Ren， Chao-Ze Wang， Meng Yang， Liang Zhang， Hui-Ying Wu， Liang Chang， Jin-Cai Wu， Biao Jin， Hua-Jian Xue， Xue-Jiao Li， Hui Liu， Guang-Wen Yu， Xue-Ying Tao， Ting Chen， Chong-Fei Liu， Wen-Bin Luo， Jie Zhou， Hai-Lin Yong， Yu-Huai Li， Feng-Zhi Li， Cong Jiang， Hao-Ze Chen， Jian-Wei Pan

▲ 集会：https://www.nature.com/articles/s41586-025-08739-z

▲摘录：量子网罗提供了一种基础设施，将具有翻新性算计、传感和通讯才能的量子开采结合起来。量子卫星星座为促进全球范围内的量子网罗提供了一种处分有规划。墨子号卫星考据了卫星量子通讯的可行性；但是，扩宽广子卫星群是具有挑战性的，需要微型轻型卫星、便携式大地站和及时安全密钥交换。

接头者处分了这些挑战，并评释了一种冒昧使用便携式大地站实行空间到大地量子密钥分发的量子微卫星的开发。微型卫星灵验载荷重约23公斤，便携式大地站重约100公斤，远隔减少1个数目级和2个数目级以上。使用这种缔造国产 av，他们演示了基于卫星的量子密钥分拨与多个大地站，并在单次卫星通落后候竣事了多达107万比特的安全密钥分享。

此外，他们将卫星—大地双向光通讯与量子通讯进行多路复用，竣事及时密钥蒸馏和安全通讯。他们还在中国和南非这两个在地球上相隔12900多公里的场合成就了一个密钥，不错对图像进行一次性pad加密。紧凑的量子灵验载荷不错很容易地拼装在现存的空间站或小卫星上，为基于卫星星座的量子和经典网罗的宽泛实践应用铺平了说念路。

▲ Abstract：A quantum network provides an infrastructure that connects quantum devices with revolutionary computing， sensing and communication capabilities. A quantum satellite constellation offers a solution to facilitate the quantum network on a global scale. The Micius satellite has verified the feasibility of satellite quantum communications; however， scaling up quantum satellite constellations is challenging， requiring small lightweight satellites， portable ground stations and real-time secure key exchange. Here we tackle these challenges and report the development of a quantum microsatellite capable of performing space-to-ground quantum key distribution using portable ground stations. The microsatellite payload weighs approximately 23 kilograms， and the portable ground station weighs about 100 kilograms， representing reductions by more than 1 and 2 orders of magnitude， respectively. Using this set-up， we demonstrate satellite-based quantum key distribution with multiple ground stations and achieve the sharing of up to 1.07 million bits of secure keys during a single satellite pass. In addition， we multiplex bidirectional satellite–ground optical communication with quantum communication， enabling key distillation and secure communication in real time. Also， a secret key， enabling one-time pad encryption of images， is created between China and South Africa at locations separated by over 12，900 kilometres on Earth. The compact quantum payload can be readily assembled on existing space stations or small satellites， paving the way for a satellite-constellation-based quantum and classical network for widespread real-life applications.

Water structure and electric fields at the interface of oil droplets

油滴界面处的水结构和电场

▲ 作家：Lixue Shi， R. Allen LaCour， Naixin Qian， Joseph P. Heindel， Xiaoqi Lang， Ruoqi Zhao， Teresa Head-Gordon & Wei Min

▲ 集会：https://www.nature.com/articles/s41586-025-08702-y

▲摘录：界面水阐扬出丰富而复杂的步履，在化学、生物、地质和工程等规模阐扬着紧迫作用。但是，对于疏水界面上的水的基人性质，如取向规则、水合氢离子和氢氧根的浓度、不符合的氢键和大电场的存在，仍然存在许多争论。即使使用着手进的实验时刻和表面按序，这种争议也源于测量界面系统的挑战。

接头者评释了一种溶液中，界面选拔性拉曼光谱按序，使用多元弧线分辨率来探伤水中十六烷乳液，并借助于拉曼光谱的单体场表面模子。接头终结标明，与平面油水界面比较，油水乳液界面不错阐扬出镌汰的四面体规则和较弱的氢键，以及宽广的解放羟基，在其拉伸方法下资格约95cm-1的红移。

洽商到已知的油滴静电zeta电位特质，他们建议了从油相发出的强电场（约50~90MVcm-1）的存在。这个场是曲折推断出来的，但有限度实验和表面揣摸的支撑。在由小溶质造成的分子疏水界面或平面油水界面中，这些不雅察终结要么不存在，要么相背。相背，水结构繁杂和增强的电场是油水乳液中圭臬界面的特有特征，可能有助于在疏水—水界面上不雅察到的加快化学响应性。

▲ Abstract：Interfacial water exhibits rich and complex behaviour， playing an important part in chemistry， biology， geology and engineering. However， there is still much debate on the fundamental properties of water at hydrophobic interfaces， such as orientational ordering， the concentration of hydronium and hydroxide， improper hydrogen bonds and the presence of large electric fields. This controversy arises from the challenges in measuring interfacial systems， even with the most advanced experimental techniques and theoretical approaches available. Here we report on an in-solution， interface-selective Raman spectroscopy method using multivariate curve resolution to probe hexadecane-in-water emulsions， aided by a monomer-field theoretical model for Raman spectroscopy. Our results indicate that oil–water emulsion interfaces can exhibit reduced tetrahedral order and weaker hydrogen bonding， along with a substantial population of free hydroxyl groups that experience about 95 cm-1 redshift in their stretching mode compared with planar oil–water interfaces. Given the known electrostatic zeta potential characteristic of oil droplets， we propose the existence of a strong electric field (about 50–90MVcm-1) emanating from the oil phase. This field is inferred indirectly but supported by control experiments and theoretical estimates. These observations are either absent or opposite in the molecular hydrophobic interface formed by small solutes or at planar oil–water interfaces. Instead， water structural disorder and enhanced electric fields emerge as unique features of the mesoscale interface in oil–water emulsions， potentially contributing to the accelerated chemical reactivity observed at hydrophobic–water interfaces.

Solidification of Earth’s mantle led inevitably to a basal magma ocean

地幔凝固导致基底岩浆海洋的造成

▲ 作家：Charles-édouard Boukaré， James Badro & Henri Samuel

▲ 集会：https://www.nature.com/articles/s41586-025-08701-z

▲摘录：对地幔深层地球物理结构的一种主要解释是，它们源于地核上方地球原始基底岩浆海洋从上至下的凝固。但是，固体是领先造成于地幔底部，朝上凝固，照旧在熔体上方，向下凝固，仍然存在争议。

接头者诠释了精采的、富铁的熔体与较轻的、贫铁的固体的引力分离开动了地幔的演化，而不论熔体弧线和地热在那儿相交。这仍是由导致富含氧化铁的熔体在地核上方积存，造成一个基底岩浆海。

他们收受一种新的多相流体能源学按序，将熔融磋议系与地球化学模子相结合，对地幔凝固经由进行了数值模拟。这不错揣摸原始地球化学储层的构成特征和空间散播，这可能与太古宙岩石中测量到的同位素额外径直磋议。

接头者发现宽广的固体是在地球名义产生的，而不是在深处，在深部地幔中注入了浅层硅酸盐分异的地球化学特征。这项职责不错为再行接头岩石行星演化的前10亿年中地幔能源学、岩石学和地球化学之间复杂的互相作用奠定基础。

▲ Abstract：One of the main interpretations of deep-rooted geophysical structures in the mantle1 is that they stem from the top-down solidification of the primitive basal magma ocean of Earth above the core. However， it remains debated whether solids first formed at the bottom of the mantle， solidifying upward， or above the melts， solidifying downward. Here we show that gravitational segregation of dense， iron-rich melts from lighter， iron-poor solids drives mantle evolution， regardless of where melting curves and geotherms intersect. This process results in the accumulation of iron-oxide-rich melts above the core， forming a basal magma ocean. We numerically model mantle solidification using a new multiphase fluid dynamics approach that integrates melting phase relations and geochemical models. This enables estimating the compositional signature and spatial distribution of primordial geochemical reservoirs， which may be directly linked to the isotopic anomalies measured in Archean rocks. We find that a substantial amount of solids is produced at the surface of the planet， not at depth， injecting geochemical signatures of shallow silicate fractionation in the deep mantle. This work could serve as a foundation for re-examining the intricate interplay between mantle dynamics， petrology and geochemistry during the first thousand million years of the evolution of rocky planets.

化学Chemistry

Phosphate-enabled mechanochemical PFAS destruction for fluoride reuse

磷酸盐开动的机械化学PFAS窒碍以竣事氟化物的再期骗

▲ 作家：Long Yang， Zijun Chen， Christopher A. Goult， Thomas Schlatzer， Robert S. Paton & Véronique Gouverneur

▲ 集会：https://www.nature.com/articles/s41586-025-08698-5 

▲ 摘录：全氟烷基和多氟烷基物资（PFASs）是抓久性、生物蓄积性和东说念主为稠浊物，因其对东说念主类健康的不利影响而引起众人和私营部门的爱护。天然已经收受了多样时刻来降解全氟辛烷磺酸，重心曲直团聚功能化化合物（全氟辛酸和全氟辛烷磺酸），但一种通用的全氟辛烷磺酸窒碍按序加上氟回登科于升级轮回曲直常可取的。

接头者裸露了一项将多种PFAS（包括氟塑料聚四氟乙烯和聚偏氟乙烯）鼎新为高价值氟化学品的合同。为了竣事这一主义，PFASs在无溶剂机械化学要求下与磷酸钾盐响应，这是一种矿化经由，不错回收氟算作KF和K2PO3F进行氟化化学。磷酸盐不错回收再期骗，这意味着对磷轮回莫得无益影响。因此，全氟化合物不仅是可窒碍的，况兼当今不错为可抓续的轮回氟经济作出孝顺。

▲ Abstract：Perfluoroalkyl and polyfluoroalkyl substances (PFASs) are persistent， bioaccumulative and anthropogenic pollutants that have attracted the attention of the public and private sectors because of their adverse impact on human health. Although various technologies have been deployed to degrade PFASs with a focus on non-polymeric functionalized compounds (perfluorooctanoic acid and perfluorooctanesulfonic acid)， a general PFAS destruction method coupled with fluorine recovery for upcycling is highly desirable.Here we disclose a protocol that converts multiple classes of PFAS， including the fluoroplastics polytetrafluoroethylene and polyvinylidene fluoride， into high-value fluorochemicals. To achieve this， PFASs were reacted with potassium phosphate salts under solvent-free mechanochemical conditions， a mineralization process enabling fluorine recovery as KF and K2PO3F for fluorination chemistry. The phosphate salts can be recovered for reuse， implying no detrimental impact on the phosphorus cycle. Therefore， PFASs are not only destructible but can now contribute to a sustainable circular fluorine economy.

Photoinduced copper-catalysed deracemization of alkyl halides

光招引铜催化烷基卤化物脱羧

▲ 作家：Feng Zhong， Renhe Li， Binh Khanh Mai， Peng Liu & Gregory C. Fu

▲ 集会：https://www.nature.com/articles/s41586-025-08784-8

▲摘录：脱消旋是一种产生对映体富集化合物的新政策，其中容易赢得的外消旋肇端材料的两个对映体鼎新为单个对映体，常常通过光招引催化剂的作用。这种潜在的重大分歧称催化按序的旨趣诠释已经被形容；但是，骨子性的挑战尚未得到处分。

接头者形容了一种处分这些挑战的简便按序，使用手性铜催化剂，由市售身分原位生成，通过碳—卤素键裂解竣事叔（和仲）烷基卤化物的光招引离中心化。机理接头（包括假定中间体的寂然合成，光物理、光谱和响应性接头以及密度泛函表面算计）为他们建议的催化轮回中的关节法子和中间体提供了支撑，并久了了解了对映体选拔性的发源。

▲ Abstract：Deracemization is an emerging strategy for generating enantioenriched compounds wherein the two enantiomers of a readily available racemic starting material are transformed into a single enantiomer， typically through the action of a light-induced catalyst. Excellent proof of principle for this potentially powerful approach to asymmetric catalysis has been described; nevertheless国产 av， substantial challenges have not yet been addressed， including the exploitation of carbon–heteroatom (rather than only carbon–hydrogen and carbon–carbon) bond cleavage to achieve deracemization， as well as the development of processes that provide broad classes of useful enantioenriched compounds and tetrasubstituted stereocentres. Here we describe a straightforward method that addresses these challenges， using a chiral copper catalyst， generated in situ from commercially available components， to achieve the photoinduced deracemization of tertiary (and secondary) alkyl halides through carbon–halogen bond cleavage. Mechanistic studies (including the independent synthesis of postulated intermediates， photophysical， spectroscopic and reactivity studies， and density functional theory calculations) provide support for the key steps and intermediates in our proposed catalytic cycle， as well as insight into the origin of enantioselectivity.

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