Science, 23 September 2022, Volume 377 Issue 6613
《科学》2022年9月23日，第377卷，6613期
化学Chemistry
Controlling the nucleation and growth kinetics of lead halide perovskite quantum dots
控制卤化铅钙钛矿量子点的成核和生长动力学
▲ 作者：QUINTEN A. AKKERMAN , TAN P. T. NGUYEN, SIMON C. BOEHME, FEDERICO MONTANARELLA, DMITRY N. DIRIN, PHILIPP WECHSLERFINN BEIGLBÖCK, GABRIELE RAINÒ , ROLF ERNI, MAKSYM V. KOVALENKO, etc.
▲ 链接：
https://www.science.org/doi/10.1126/science.abq3616
▲ 摘要：
具有更多共价键的无机材料，如硒化镉，在快速生长条件下形成均匀的纳米颗粒，但钙钛矿，如溴化铯铅（CsPbBr3）具有更多离子，并快速生长形成更大的纳米颗粒。
作者通过使用氧化三辛基膦控制纳米颗粒的生长动力学，该氧化三辛基膦可溶解PbBr2前体，结合到阳离子-[PbBr3]单体（溶质）上，并与晶核表面弱配位。
用长链两性离子卵磷脂对直径在3 ~ 13纳米之间的纳米粒子进行稳定和高产分离。在铯和有机阳离子中发现了四种高分辨的激子跃迁，其约束能量与大小有关。
▲ Abstract：
Inorganic materials with more covalent bonding, such as cadmium selenide, form uniform nanoparticles under fast growth conditions, but perovskites such as cesium lead bromide (CsPbBr3) are more ionic and grow rapidly to form larger nanoparticles. Akkerman et al. controlled the nanoparticles’ growth kinetics by using trioctylphosphine oxide, which solubilized the PbBr2 precursor, bound to the cation-[PbBr3] monomer (solute), and weakly coordinated to the crystal nuclei surfaces. Nanoparticles with diameters from 3 to 13 nanometers were stabilized and isolated in high yield with lecithin, a long-chain zwitterion. Four well-resolved excitonic transitions with size-dependent confinement energies were seen for cesium as well as organic cations.
Deterministic fabrication of 3D/2D perovskite bilayer stacks for durable and efficient solar cells
用于耐用和高效太阳能电池的3D/2D钙钛矿双层叠置的确定性制造
▲ 作者：SIRAJ SIDHIK, YAFEI WANGMICHAEL DE SIENA, REZA ASADPOUR, ANDREW J. TORMA , TANGUY TERLIER, KEVIN HO, ADITYA D. MOHITE
▲ 链接：
https://www.science.org/doi/10.1126/science.abq7652
▲ 摘要：
二维卤化物钙钛矿钝化层生长在三维钙钛矿上可以提高太阳能电池的功率转换效率，但这些层的旋涂通常形成非均匀的二维相或只形成超薄层。
作者发现，具有适当介电常数和供体强度的溶剂可以在3D衬底上生长控制厚度和组成的相纯二维相，而不会溶解它们。在55°C和65%相对湿度的持续光照下，太阳能电池在2000小时内保持了24.5%的峰值功率转换效率，降解低于1%。
▲ Abstract：
Two-dimensional (2D) halide perovskite passivation layers grown on three-dimensional (3D) perovskite can boost the power conversion efficiency (PCE) of solar cells, but spin-coating of these layers usually forms heterogeneous 2D phases or only ultrathin layers. Sidhik et al. found that solvents with the appropriate dielectric constant and donor strength could grow phase-pure 2D phases of controlled thickness and composition on 3D substrates without dissolving them. Solar cells maintained a peak PCE of 24.5% for 2000 hours with less than 1% degradation under continuous light at 55°C and 65% relative humidity.
物理学Quantum Physics & Geophysics
Provably efficient machine learning for quantum many-body problems
量子多体问题的可证明有效的机器学习
▲ 作者：HSIN-YUAN HUANG, RICHARD KUENG, GIACOMO TORLAI , VICTOR V. ALBERT, AND JOHN PRESKILL
▲ 链接：
https://www.science.org/doi/10.1126/science.abk3333
▲ 摘要：
预测强相互作用多体量子系统的性质是出了名的困难。一种方法是使用量子计算机，但在目前的技术阶段，最有趣的问题仍然无法触及。
作者探索了一种不同的技术：使用经典机器学习从实验数据中学习，然后应用这些知识来预测物理性质或对特定类型的多体问题的物质相进行分类。结果表明，在一定条件下，该算法具有较高的计算效率。
▲ Abstract：
Predicting the properties of strongly interacting many-body quantum systems is notoriously difficult. One approach is to use quantum computers, but at the current stage of the technology, the most interesting problems are still out of reach. Huang et al. explored a different technique: using classical machine learning to learn from experimental data and then applying that knowledge to predict physical properties or classify phases of matter for specific types of many-body problems. The authors show that under certain conditions, the algorithm is computationally efficient.
Water vapor injection into the stratosphere by Hunga Tonga-Hunga Ha’apai
汤加洪阿哈阿帕伊岛火山向平流层注入水汽
▲ 作者：HOLGER VOMEL, STEPHANIE EVAN, AND MATT TULLY
▲ 链接：
https://www.science.org/doi/10.1126/science.abq2299
▲ 摘要：
2022年1月，汤加海底火山洪阿哈阿帕伊岛火山的喷发非常猛烈，其羽流渗透到平流层。作者研究了无线电探空仪（气象气球）的现场测量结果，结果表明这一事件向平流层注入了至少50太克的水蒸气。
因为火山是在水下的，在发展的平流层羽流中的水蒸气量很高，而且，与其他大型喷发不同的是，它可能使全球平流层水蒸气量增加了5%以上。
▲ Abstract：
The eruption of the submarine volcano Hunga Tonga-Hunga Ha’apai in January of 2022 was so violent that its plume penetrated into the stratosphere. Vömel et al. studied in situ measurements by radiosondes (weather balloons), which showed that the event injected at least 50 teragrams of water vapor into the stratosphere. Because the volcano was underwater, the amount of water vapor in the developing stratospheric plume was high, and, unlike other large eruptions, it may have increased the amount of global stratospheric water vapor by more than 5%.
气候与生态Climate & Ecology
Limited climate change mitigation potential through forestation of the vast dryland regions
通过大面积旱地地区造林缓解气候变化的潜力有限
▲ 作者：SHANI ROHATYN, DAN YAKIR, EYAL ROTENBERG, AND YOHAY CARMEL
▲ 链接：
https://www.science.org/doi/10.1126/science.abm9684
▲ 摘要：
有人建议在全球旱地植树造林是减缓全球变暖的一种方法，但这在实际上有多大的希望？作者发现，气候变化带来的好处很小。
虽然旱地有相当大的固碳潜力，可以用来减少大气中的二氧化碳量，从而减缓变暖，但造林造成的反照率的减少将抵消大部分这种影响。因此，尽管植树造林显然很重要，但它不能取代减排。
▲ Abstract：
Forestation of the global drylands has been suggested to be a way to decrease global warming, but how much promise does it actually have? Rohatyn et al. found that the climatic benefits are minor. Although drylands have considerable carbon sequestration potential, which could be used to lower the amount of carbon dioxide in the atmosphere and thereby slow warming, the reduction of albedo caused by forestation would counteract most of that effect. So, although forestation is clearly important, it cannot substitute for reducing emissions. —HJS
Termite sensitivity to temperature affects global wood decay rates
白蚁对温度的敏感性影响全球木材的衰变率
▲ 作者：AMY E. ZANNE, HABACUC FLORES-MORENO, JEFF R. POWELL, WILLIAM K. CORNWELL, KEI-ICHI OKADA, PAUL-CAMILO ZALAMEA, etc.
▲ 链接：https://www.science.org/doi/10.1126/science.abo3856
▲ 摘要：
分解速率随温度和降水的变化而变化，部分原因是气候对分解生物的影响。尽管微生物被广泛认为是分解者，但昆虫等动物在热带系统中也发挥着关键作用。
作者在全球133个地点重复了一项实验，以量化微生物和白蚁在木材分解中与气候相关的变化。结果发现气候对微生物和白蚁的分解均有影响，但白蚁的存在和活性对温度更为敏感。因此，随着气候变暖，白蚁可能在全球木材分解中发挥更大的作用。
▲ Abstract：
Decomposition rates vary with temperature and precipitation, in part because of the effects of climate on decomposer organisms. Although microbes are widely recognized as decomposers, animals such as insects also play a key role in tropical systems. Zanne et al. replicated an experiment at 133 global sites to quantify climate-related variation in wood decomposition by both microbes and termites. Climate influenced both microbial and termite decomposition, but termite presence and activity were more sensitive to temperature. Termites may thus play a larger role in global wood decomposition as the climate warms.
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