編譯|未玖
Nature, 19 June 2025, Volume 642, Issue 8068
《自然》2025年6月19日，第642卷，8068期
天文學Astronomy
Detection of X-ray emission from a bright long-period radio transient
明亮長周期射電瞬變X射線發射
▲ 作者：Ziteng Wang, Nanda Rea, Tong Bao, David L. Kaplan, Emil Lenc, Zorawar Wadiasingh, et al.
▲鏈接：
https://www.nature.com/articles/s41586-025-09077-w
▲ 摘要： 最近，研究人員發現了一類長周期射電瞬變（LPTs），其發射時間比射電脈沖星長數千倍。該發現得益于廣域無線電調查的進展，這對現有的旋轉動力脈沖星模型提出了挑戰。目前提出的理論模型包括高磁化中子星、白矮星脈沖星以及伴星為低質量恒星的白矮星雙星系統。盡管某些模型預測存在X射線輻射，但經過廣泛搜尋后，尚未在任何LPTs中探測到X射線信號。
研究人員發現了一個極其明亮的LPT（射電10~20 Jy）ASKAP J1832?0911，其具有同步的射電和X射線發射——兩者周期均為44.2分鐘。ASKAP J1832?0911高度相關且變化劇烈的X射線和射電光度，再加上其他觀測特性，使其不同于任何已知的銀河系天體。其可能是一顆古老的磁星或一顆超磁化白矮星，但這兩種解釋都存在理論上的挑戰。
LPT的X射線探測表明，這些天體的能量比此前想象的要高，并建立了一類小時尺度的周期性X射線瞬變，其光度約為1033?erg?s-1，與異常明亮的相干射電發射有關。
▲ Abstract： Recently, a class of long-period radio transients (LPTs) has been discovered, exhibiting emission thousands of times longer than radio pulsars. These findings, enabled by advances in wide-field radio surveys, challenge existing models of rotationally powered pulsars. Proposed models include highly magnetized neutron stars, white-dwarf pulsars and white-dwarf binary systems with low-mass companions. Although some models predict X-ray emission, no LPTs have been detected in X-rays despite extensive searches. Here we report the discovery of an extremely bright LPT (10–20?Jy in radio), ASKAP?J1832?0911, which has coincident radio and X-ray emission, both with a 44.2-minute period. Its correlated and highly variable X-ray and radio luminosities, combined with other observational properties, are unlike any known Galactic object. The source could be an old magnetar or an ultra-magnetized white dwarf; however, both interpretations present theoretical challenges. This X-ray detection from an LPT reveals that these objects are more energetic than previously thought and establishes a class of hour-scale periodic X-ray transients with a luminosity of about 1033?erg?s?1 linked to exceptionally bright coherent radio emission.
材料科學Material Science
Vertically stacked monolithic perovskite colour photodetectors
垂直堆疊的單片鈣鈦礦彩色光電探測器
▲ 作者：Sergey Tsarev, Daria Proniakova, Xuqi Liu, Erfu Wu, Gebhard J. Matt, Kostiantyn Sakhatskyi, et al.
▲鏈接：
https://www.nature.com/articles/s41586-025-09062-3
▲ 摘要： 由于光利用效率的固有局限性，現代彩色圖像傳感器在進一步提高靈敏度和圖像質量方面頗具挑戰。造成這些局限性的一個主要因素是使用被動式濾光片。它吸收和消散大量的入射光，從而降低了光捕獲效率。相反，由于缺乏顏色選擇性，Foveon型垂直堆疊架構中的主動濾光技術仍難以提供最佳性能，使其在精準彩色成像方面效率低下。
研究人員介紹了一種顏色傳感器陣列的創新架構，使用多層單片堆疊鹵化鉛鈣鈦礦薄膜光電探測器。鈣鈦礦帶隙可調性用于選擇性地吸收可見光光譜的紅、綠和藍波段，從而消除了對濾光片的需求。 紅、綠和藍通道的外部量子效率分別達到50%、47%和53%，在ΔELab中顏色精度為3.8%，優于目前最先進的濾色陣列和Foveon型光傳感器。該圖像傳感器設計提高了色彩傳感器的光利用率，為新一代高靈敏度、高色彩保真度、無偽影成像奠定了基礎。
▲ Abstract： Modern colour image sensors face challenges in further improving sensitivity and image quality because of inherent limitations in light utilization efficiency. A major factor contributing to these limitations is the use of passive optical filters, which absorb and dissipate a substantial amount of light, thereby reducing the efficiency of light capture. On the contrary, active optical filtering in Foveon-type vertically stacked architectures still struggles to deliver optimal performance owing to their lack of colour selectivity, making them inefficient for precise colour imaging. Here we introduce an innovative architecture for colour sensor arrays that uses multilayer monolithically stacked lead halide perovskite thin-film photodetectors. Perovskite bandgap tunability is utilized to selectively absorb the visible light spectrum’s red, green and blue regions, eliminating the need for colour filters. External quantum efficiencies of 50%, 47% and 53% are demonstrated for the red, green and blue channels, respectively, as well as a colour accuracy of 3.8% in ΔELab outperforming the state-of-the-art colour-filter array and Foveon-type photosensors. The image sensor design improves light utilization in colour sensors and paves the way for the next generation of highly sensitive, artefact-free images with enhanced colour fidelity.
Light-triggered regionally controlled n-doping of organic semiconductors有機半導體的光觸發區域可控n型摻雜
▲ 作者：Xin-Yi Wang, Yi-Fan Ding, Xiao-Yan Zhang, Yang-Yang Zhou, Chen-Kai Pan, Yuan-He Li, et al.
▲鏈接：
https://www.nature.com/articles/s41586-025-09075-y
▲ 摘要： 摻雜是調制半導體電性能的主要方法，可以制造各種同質結/異質結和復雜器件。對于有機半導體（OSCs），通過開發摻雜方法和摻雜劑，其電性能得到了廣泛的改善。然而，與最先進的無機半導體制造工藝的空間分辨率相比，OSC遠遠落后，這限制了復雜有機電子器件的構建。 研究人員提出了一種簡單的光觸發摻雜策略，并開發了一系列非活性的光激活摻雜劑（iPAD），用于OSC的區域可控n型摻雜。通過紫外線（UV）照射將iPAD轉化為活性摻雜劑，實現了對各種n型OSC的可控摻雜，電導率高達30?S?cm-1。使用iPAD可顯著提升OSC在晶體管、邏輯電路和熱電器件中的性能。
此外，在OSC中也實現了記錄分辨率低至1 μm的區域可控摻雜。總而言之，該策略在OSC中實現了可調的摻雜水平，具有高空間分辨率，將助力卷對卷和實驗室規模環境中的集成電路制造。
▲ Abstract： Doping is a primary method to modulate the electrical properties of semiconductors, enabling the fabrication of various homojunctions/heterojunctions and complex devices. For organic semiconductors (OSCs), the electrical performance has been extensively improved by developing doping methods and dopants. However, compared with the state-of-the-art spatial resolution of inorganic semiconductor fabrication processes, OSCs lag far behind, limiting the construction of complex organic electronic devices. Here we present a facile light-triggered doping strategy and develop a series of inactive photoactivable dopants (iPADs) for regionally controlled n-doping of OSCs. By converting iPADs into active dopants through ultraviolet (UV) exposure, controllable doping of various n-type OSCs with high electrical conductivity greater than 30?S?cm?1 has been realized. Using iPADs can substantially improve the performances of OSCs in transistors, logic circuits and thermoelectrics. Also, regionally controlled doping is demonstrated in OSCs with a record resolution down to 1?μm. Overall, our strategy has achieved tunable doping levels in OSCs with high spatial resolution, which is expected to be highly suited for integrated circuits in both roll-to-roll and laboratory-scale environments.
化學Chemistry
Coordination environments of Pt single-atom catalysts from NMR signatures
核磁共振特征助力解析Pt單原子催化劑的配位環境
▲ 作者：Jonas Koppe, Alexander V. Yakimov, Domenico Gioffrè, Marc-Eduard Usteri, Thomas Vosegaard, Guido Pintacuda, et al.
▲鏈接：
https://www.nature.com/articles/s41586-025-09068-x
▲摘要：將原子分散物種與受控結構結合在一起的負載型金屬催化劑處于催化材料設計的前沿。該方法可精準控制反應性，具有高金屬利用率，且接近分子系統的精度。然而，準確解析局部金屬配位環境仍頗具挑戰性，阻礙了優化其設計以適應多種應用所需的結構-活性關系的進展。
盡管電子顯微鏡揭示了原子的分散，但在多相催化中使用的傳統光譜方法只能提供平均結構信息。
研究人員證明195Pt固態核磁共振（NMR）光譜是表征各種載體上原子分散Pt位點的有力工具，即所謂的單原子催化劑（SACs）。蒙特卡羅模擬實現了將NMR光譜轉換為SAC特征，以分子精度描述配位環境，從而能夠定量評估Pt位點的分布和均勻性。
該方法可以跟蹤合成參數的影響，揭示特定步驟和負載類型的影響，還可以監測反應的變化，為具有目標結構SAC的可重復性開發提供了關鍵見解。除SAC之外，該策略還為研究更復雜的結構奠定了基礎，例如含有各種NMR活性金屬的雙原子或單簇催化劑。
▲ Abstract： Supported metal catalysts that integrate atomically dispersed species with controlled structures lie at the forefront of catalytic materials design, offering exceptional control over reactivity and high metal utilization, approaching the precision of molecular systems. However, accurately resolving the local metal coordination environments remains challenging, hindering the advancement of structure–activity relationships needed to optimize their design for diverse applications. Although electron microscopy reveals atomic dispersion, conventional spectroscopic methods used in heterogeneous catalysis only provide average structural information. Here we demonstrate that 195Pt solid-state nuclear magnetic resonance (NMR) spectroscopy is a powerful tool for characterizing atomically dispersed Pt sites on various supports, so called single-atom catalysts (SACs). Monte Carlo simulations allow the conversion of NMR spectra into SAC signatures that describe coordination environments with molecular precision, enabling quantitative assessment of Pt-site distribution and homogeneity. This methodology can track the influence of synthetic parameters, uncovering the impact of specific steps and support types, and can also monitor changes upon reaction. It offers critical insights for the reproducible development of SACs with targeted structures. Beyond SACs, this approach lays the foundation for studying more complex architectures, such as dual-atom or single-cluster catalysts, containing various NMR-active metals.
地球科學Earth Science
Warming accelerates global drought severity
氣候變暖加劇了全球干旱的嚴重性
▲ 作者：Solomon H. Gebrechorkos, Justin Sheffield, Sergio M. Vicente-Serrano, Chris Funk, Diego G. Miralles, Jian Peng, et al.
▲鏈接：
https://www.nature.com/articles/s41586-025-09047-2
▲ 摘要： 干旱是影響全球環境、經濟和人口的最常見、最復雜的自然災害之一。然而，全球干旱趨勢存在重大不確定性。人們對關鍵驅動因素——大氣蒸發需求（AED）在多大程度上影響干旱的程度、頻率、持續時間和面積范圍最新演變的認識有限。
通過分析1901—2022年的高分辨率全球干旱數據集，研究人員發現全球干旱嚴重程度呈上升趨勢。該研究結果表明，AED使全球干旱嚴重程度平均增加了40%。不僅典型的干旱地區變得更干燥，潮濕地區也出現了干旱趨勢。
在過去的5年間（2018—2022年），干旱地區與1981—2017年相比平均擴大了74%，其中AED貢獻了58%。2022年是破紀錄的一年，全球30%的陸地面積受到中度和極端干旱的影響，其中42%歸因于AED的增加。
該研究結果表明，AED在導致嚴重干旱方面發揮著越來越重要的作用，且在未來的變暖情景下，這種趨勢可能會持續下去。
▲ Abstract： Drought is one of the most common and complex natural hazards affecting the environment, economies and populations globally. However, there are significant uncertainties in global drought trends, and a limited understanding of the extent to which a key driver, atmospheric evaporative demand (AED), impacts the recent evolution of the magnitude, frequency, duration and areal extent of droughts. Here, by developing an ensemble of high-resolution global drought datasets for 1901–2022, we find an increasing trend in drought severity worldwide. Our findings suggest that AED has increased drought severity by an average of 40% globally. Not only are typically dry regions becoming drier but also wet areas are experiencing drying trends. During the past 5?years (2018–2022), the areas in drought have expanded by 74% on average compared with 1981–2017, with AED contributing to 58% of this increase. The year 2022 was record-breaking, with 30% of the global land area affected by moderate and extreme droughts, 42% of which was attributed to increased AED. Our findings indicate that AED has an increasingly important role in driving severe droughts and that this tendency will likely continue under future warming scenarios.
Drivers of the extreme North Atlantic marine heatwave during 2023
2023年北大西洋極端海洋熱浪的驅動因素
▲ 作者：Matthew H. England, Zhi Li, Maurice F. Huguenin, Andrew E. Kiss, Alex Sen Gupta, Ryan M. Holmes, et al.
▲鏈接：
https://www.nature.com/articles/s41586-025-08903-5
▲摘要：北大西洋環流和溫度模式深刻地影響著所有時間尺度上的全球和區域氣候，從天氣到季節、年代際、多年代際和更長時間。2023年，北半球夏季發生了一場極端的近盆地規模海洋熱浪，并在7月達到峰值。變暖幾乎蔓延到北大西洋的所有地區，包括亞極地海洋，在過去的50~100年間，其降溫趨勢與經向翻轉環流的減緩有關。然而，導致海洋表面異常變暖的機制尚不清楚。
研究人員利用觀測約束的大氣再分析以及海洋觀測和模型模擬，表明作用于極淺表面混合層的空氣-海洋熱通量，而不是異常的海洋熱輸送，是造成這一極端海洋變暖事件的原因。其主要驅動因素是異常弱風導致混合層強烈淺化，造成北大西洋淺表層溫度迅速升高。
此外，太陽輻射異常在與該地區一些主要航道大致對應的位置造成了區域尺度的變暖，這表明硫酸鹽排放的減少也可能發揮了局部作用。近幾十年來觀測到的混合層變淺的趨勢，以及對這種趨勢將持續到未來的預測，北大西洋海洋熱浪的嚴重程度將進一步惡化。
▲ Abstract： North Atlantic Ocean circulation and temperature patterns profoundly influence global and regional climate across all timescales, from synoptic to seasonal, decadal, multidecadal and beyond. During 2023, an extreme and near-basin-scale marine heatwave developed during Northern Hemisphere summer, peaking in July. The warming spread across virtually all regions of the North Atlantic, including the subpolar ocean, where a cooling trend over the past 50–100?years has been linked to a slowdown in the meridional overturning circulation. Yet the mechanisms that led to this exceptional surface ocean warming remain unclear. Here we use observationally constrained atmospheric reanalyses alongside ocean observations and model simulations to show that air–sea heat fluxes acting on an extremely shallow surface mixed layer, rather than anomalous ocean heat transport, were responsible for this extreme ocean warming event. The dominant driver is shown to be anomalously weak winds leading to strongly shoaling (shallowing) mixed layers, resulting in a rapid temperature increase in a shallow surface layer of the North Atlantic. Furthermore, solar radiation anomalies made regional-scale warming contributions in locations that approximately correspond to some of the region’s main shipping lanes, suggesting that reduced sulfate emissions could also have played a localized role. With a trend towards shallower mixed layers observed over recent decades, and projections that this will continue into the future, the severity of North Atlantic marine heatwaves is set to worsen.
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