日前，加州理工学院Garnet Kin-Lic Chan教授课题组展示了一种数值策略，在有效低能模型的解决方案之外，在完全从头计算水平上模拟关联材料，并将其应用于在母态未掺杂状态的铜酸盐超导材料家族中获得详细的微观理解。该工作提供了一条在从头计算多体水平上对关联材料的更复杂状态进行定量和可靠理解的途径。该工作以题为“Systematic electronic structure in the cuprate parent state from quantum many-body simulations”发表在Science上，第一作者为博士生崔智昊。中科幻彩为其成果设计制作了论文插图。

文中插图制作：中科幻彩

量子多体模拟揭示铜酸盐母态的系统电子结构

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https://www.science.org/doi/10.1126/science.abm2295

本文证明通过结合量子嵌入、从头算量子求解器和周期性量子化学的数值策略，可以在多体水平上确定铜酸盐母态中材料特定的关联电子结构。这揭示了费米分布和准粒子中多轨道键合和

关联效应的趋势，并给出了低能磁激发的定量描述

铜酸盐与母态及计算技术

铜酸盐的主要结构特征是二维（2D）CuO₂（形式为[CuO₂]^2-）方晶格平面（图1A)。在不同的铜酸盐中，铜-氧平面在垂直方向上被不同的原子和缓冲层所包围。除了层堆叠的理想CuO₂平面，作者考虑了三种特定的化合物。第一个是无限层CaCuO2（CCO）（图1D），其中钙反离子以无限重复的结构插入在CuO₂平面之间。CCO本身不具有超导性。然而，在相关的汞-钡铜酸盐（Hg-Ba-Ca-Cu-O家族）中观察到高温（T c）超导。CuO₂平面由顶端氧修饰，顶端氧连接到汞和钡离子的缓冲层。与CCO不同的是，缓冲层在铜-氧层之间形成了较大的间隔层。不同缓冲层之间有不同数量的CuO₂平面，可以合成不同的汞-钡铜酸盐，导致单层铜酸盐，双层铜酸盐等等。作者考虑了这个家族中的两个成员：HgBa2CuO 4（Hg-1201；单层，T c = 97 K）和HgBa 2CaCu 2O 6（Hg-1212；双层，T c = 127 K）。Hg-1201表现出扭曲的八面体Cu-O配位（每个Cu包含两个顶端氧）（图1B)，而Hg-1212每层都包含锥体Cu-O配位（每个Cu包含一个顶端氧）（图1C)。Hg-1201、Hg-1212和CCO通过用Ca层取代Hg-Ba-顶端O层而组成相关。作者在母态的磁性特征与材料的原子级结构和电子特征之间建立了因果关系与定量关系。

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图1. 结构和计算策略

同时，新加坡国立大学的Wei Sun Leong教授对北航杨树斌教授的工作以前对铜酸盐电子结构的数值研究[除了少数例外]分为两类：(i)从头计算等位电子模拟与适度处理电子关联，它们常被用来推导出低能量的有效模型；（ii）精确的多体方法应用于低能量有效模型，以获得相图和更奇异的阶。作者的策略是使用与（ii）的模型研究相关的一系列方法，但在技术上提升到 (i) 的完全从头算哈密顿量。作者从Hg-1201、Hg-1212、CCO和[CuO 2] 2-系列的一般电子趋势开始，作为在后面部分理解物理趋势的基线。作者首先从2×2计算超级单体中提取阶参数：电荷、局部矩、键序和自旋相关函数（图2A至E）。进行了评述，并发表在Nature上。评述中指出：这种方法可以直接将非范德华固体材料转变为单层TMCs，极具普适性，且操作简便，成本低廉，非常适合工业生产，将二维材料的应用极大地推向了市场商业化。从科学本身角度而言，杨树斌教授团队的最新研究工作表表明，少量（<1％）杂原子的掺杂可以稳定单层过渡金属硫族化物，用于解决二维材料在环境中的不稳定性，这为材料研究人员提供了新的思路：应当开始探索使用化学元素来稳定二维材料，而不用再使用包覆等复杂策略。

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图2. 电荷、自旋和键序

关于作者

崔智昊，从初中开始就着迷于化学实验。高中就读于太原五中，高二时，他拿到了全国化学竞赛初赛的一等奖；高三入选省队参加第26届全国高中生化学竞赛获得金牌；随后入选国家队，代表我国中学生参加第45届国际化学奥林匹克竞赛，斩获国际化学奥赛金牌，同年被保送到北京大学化学学院。一路开挂，在北大就读期间，获2015-2016学年国家奖学金，以第一作者身份,Phys. Chem. Phys. Chem., 2016, 18, 29914-29922; J. Phys. Chem. C 2017, 121, 6, 3241–3251；J. Phys. Chem. Lett. 2018, 9, 9, 2338–2345发表论文3篇。以参与作者在Nature Materials, J. Mater. Chem. A等顶尖期刊发表论文。2017年从北大毕业后，前往加州理工学院求学，从事强相关的材料和相关的电子结构方法研究，如今问鼎Science!

中稿插图·一周精选

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Titel

Interfacial engineering to achieve an energy

density of over 200 Wh kg−1 in sodium batteries

DOI

https://www.nature.com/articles/s41560-022-01033-6

Abstract （上下滑动查看）

Sodium-based batteries have attracted wide interests in the academic and industrial fields. However, their energy density

is still lower than that of Li-based batteries. Here we report an initial anode-free Na battery with an energy density of over

200 Wh kg−1, which is even higher than that of the commercial LiFePO4||graphite battery. Through introducing graphitic carbon

coating on the Al current collector and boron-containing electrolytes in the battery, we show that uniform nucleation and robust

interphases enable reversible and crack-free Na deposition. Benefitting from the synergetic effects derived from the built coop

erative interfaces, the cycling lifetime of the Na battery without applying additional pressure reaches 260 cycles, which is the

longest life for large-size cells with zero excess Na. The insights gained from the Na plating/stripping behaviour and interfacial

chemistry in this work pave the way for further development of Na batteries with even higher performance.

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Titel

Comprehensive 3D epigenomic maps defifine limbal

stem/progenitor cell function and identity

DOI

https://www.nature.com/articles/s41467-022-28966-6

Abstract （上下滑动查看）

The insights into how genome topology couples with epigenetic states to govern the function

and identity of the corneal epithelium are poorly understood. Here, we generate a high

resolution Hi-C interaction map of human limbal stem/progenitor cells (LSCs) and show that

chromatin multi-hierarchical organisation is coupled to gene expression. By integrating Hi-C,

epigenome and transcriptome data, we characterize the comprehensive 3D epigenomic

landscapes of LSCs. We fifind that super-silencers mediate gene repression associated with

corneal development, differentiation and disease via chromatin looping and/or proximity.

Super-enhancer (SE) interaction analysis identifified a set of SE interactive hubs that contribute

to LSC-specifific gene activation. These active and inactive element-anchored loop networks

occur within the cohesin-occupied CTCF-CTCF loops. We further reveal a coordinated reg

ulatory network of core transcription factors based on SE-promoter interactions. Our results

provide detailed insights into the genome organization principle for epigenetic regulation of

gene expression in stratifified epithelia.

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Titel

Bio-Inspired Self-Hydrophobized Sericin Adhesive with

Tough Underwater Adhesion Enables Wound Healing

and Fluid Leakage Sealing

DOI

https://doi.org/10.1002/adfm.202201108

Abstract （上下滑动查看）

Given that adhesion-resistance of water severely weakens the bonding

strength of tissue adhesives, instant adhesion to wet biological tissue

surfaces remains challenging. Inspired by the robust underwater adhesion

of natural creatures (such as mussels and barnacles whose underwater

adhesion derives from the synergy of hydrophobic and adhesive matrix), a

self-hydrophobized adhesive is developed by co-assembly of disulfide-bond

hydrolyzed hydrophobic natural sericin protein (a major component of silk

worm silk fibers) and tannic acid. Once exposed to water, the self-aggregation

of hydrophobic chains within the adhesive repels water and enhances inter

facial hydrogen bonding or electrostatic interactions, mechanistically leading

to a robust (>0.5 MPa for solid plates and >0.1 MPa for tissues) and durable

(still maintained at 0.4 Mpa even after five cycles) underwater adhesion.

Owing to its robust underwater adhesion property, this adhesive possesses

multiple advantages outperforming commercial adhesives, such as in vivo

wound healing-promoting effects, effective fluid leakage sealing, and rapid

hemostasis activity. This study not only offers a novel strategy for designing

and fabricating an underwater adhesive with natural protein but also pro

vides a new adhesive for various potential applications, including promoting

wound healing and hemostasis.

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itel

Biodegradation of polystyrene and low-density polyethylene by Zophobas

atratus larvae: Fragmentation into microplastics, gut microbiota shift, and

microbial functional enzymes

DOI

https://doi.org/10.1016/j.jclepro.2022.132987

Abstract （上下滑动查看）

In this study, biodegradation of polystyrene (PS) and low-density polyethylene (LDPE) by Zophobas atratus larvae

was characterized to investigate fragmentation of ingested polymers, larval physiology, gut microbiota, and

microbial functional enzymes over a 28-day test. The larvae maintained high survival rates and low cannibal

rates, but their body fat content decreased when fed with PS or LDPE with respective consumption rates of 43.3

± 1.5 and 52.9 ± 3.1 mg plastics/100 larvae per day. The larvae biodegraded PS via broad depolymerization and

LDPE via limited-extent depolymerization. The ingested PS and LDPE were fragmented into microplastics with a

mean size of 174 and 185 μm on a volume basis, and the particles with a size of 6.3 and 5.9 μm reached a

maximum number, respectively, with no nanoplastics generated. Chemical modifications of the polymers were

confirmed. Significant shifts and clustering in the gut microbiota were detected with the relative abundance of

Citrobacter sp. increasing when PS and LDPE were fed, as reported for other species of Tenebrionidae. Microbial

functional enzymes, possibly associated with plastic degradation, including arylesterase and serine-hydrolase,

were upregulated in both PS-fed and PE-fed larvae. This work provides new insights into insect-mediated

biodegradation of persistent plastics for future investigations.

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Titel

The Yin and Yang of the protein corona on the delivery journey of nanoparticles

DOI

https://doi.org/10.1007/s12274-022-4849-6

Abstract （上下滑动查看）

Nanoparticles-based drug delivery systems have attracted significant attention in biomedical fields because they can deliver

loaded cargoes to the target site in a controlled manner. However, tremendous challenges must still be overcome to reach the

expected targeting and therapeutic efficacy in vivo. These challenges mainly arise because the interaction between nanoparticles

and biological systems is complex and dynamic and is influenced by the physicochemical properties of the nanoparticles and the

heterogeneity of biological systems. Importantly, once the nanoparticles are injected into the blood, a protein corona will

inevitably form on the surface. The protein corona creates a new biological identity which plays a vital role in mediating the

bio–nano interaction and determining the ultimate results. Thus, it is essential to understand how the protein corona affects the

delivery journey of nanoparticles in vivo and what we can do to exploit the protein corona for better delivery efficiency. In this

review, we first summarize the fundamental impact of the protein corona on the delivery journey of nanoparticles. Next, we

emphasize the strategies that have been developed for tailoring and exploiting the protein corona to improve the transportation

behavior of nanoparticles in vivo. Finally, we highlight what we need to do as a next step towards better understanding and

exploitation of the protein corona. We hope these insights into the “Yin and Yang” effect of the protein corona will have profound

implications for understanding the role of the protein corona in a wide range of nanoparticles.

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Titel

Ultraviolet Photodetectors Based on Polymer Microwire Arrays

toward Wearable Medical Devices

DOI

https://doi.org/10.1021/acsami.2c04169

Abstract （上下滑动查看）

Polymer micro/nanoarchitectures have attracted intense

interest for wearable medical applications due to their excellent mechanical

flexibility, solution processability, and tunable optoelectronic properties. Based

on polymer micro/nanostructures, high-performance ultraviolet (UV) photo

detectors can not only functionalize the accurate image sensing but also sustain

the biocomfortable flexible devices for real-time health monitoring. The main

challenges are focused on the integration of medical wearable devices, which

requires large-scale assembly of polymer micro/nanostructures with controlled

morphology and strict alignment. Herein, we utilized a confined assembly

system through the cautious regulation for the growth of high-quality polymer

1D arrays. UV photodetectors based on these polymer microwire arrays

perform a high on/off ratio of 137 and responsivity of 19.1 mA W−1. Polymer

microarray photodetectors facilitate the scale-up fabrication of 14 × 18

multiplexed image sensors for highly accurate capturing the signals of Arabic numerals “1,” “2,” and “3.” Flexible UV photodetectors

based on these arrays present excellent flexibility and bending durability, maintaining 97% of their original on/off ratio after 4000

cycles with a 10 mm bending radius. UV photodetection signals were also collected from the attached flexible devices on the back

skin of the mouse, demonstrating the great potential in wearable medical photodetection.

Titel

Selection of growth monomers on the 4H-SiC (0001) atomic step surfaces:

From the first-principles calculations to homo-epitaxy verification

DOI

https://doi.org/10.1016/j.apsusc.2022.154949

Abstract （上下滑动查看）

Silicon carbide (SiC) has gained increased interest due to industry demand, especially for the 4H-SiC. Never

theless, the ‘structural mutation’ in the 4H-SiC epitaxy is in urgent need of investigation and proper solution as

the epitaxial thickness/wafer size increases. In this study, growth monomers in the step-flow mode were firstly

investigated by the first-principles calculations for their dynamic and kinetic behaviours from an atomic level.

The stability (by the comprehensive analyses of total energies, chemical potentials, and formation enthalpies)

and the location of adsorptions were studied to reveal the dynamics. Meanwhile, the potential barrier of Si-Si

interaction and phonon spectra were determined to understand the kinetics. We found monomers could be

selected by controlling chemical potentials to make ordering growth. Secondly, two methods were thus inferred

to select monomers to adsorb on atomic step surfaces in an orderly fashion and were verified in a six-inch

epitaxy. Thirdly, a protocol was designed to restrict the extension of basal plane dislocation (BPD) from sub

strates, a reduction greater than five orders of magnitude was gained but without time compromise in the thick

film epitaxy. This study provided new insights into growth on the 4H-SiC (0001) atomic step surfaces and a new

way of 4H-SiC homo-epitaxy.

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Titel

Detection of biosignatures in Terrestrial analogs of Martian regions:

Strategical and technical assessments

DOI

https://doi.org/

10.26464/epp2022042

Abstract （上下滑动查看）

For decades, the search for potential signs of Martian life has attracted strong international interest and has led to significant

planning and scientific implementation. Clearly, in order to detect potential life signals beyond Earth, fundamental questions, such as

how to define such terms as “life” and “biosignature”, have been given considerable attention. Due to the high costs of direct exploration

of Mars, Mars-like regions on Earth have been invaluable targets for astrobiological research, places where scientists could practice the

search for “biosignatures” and refine ways to detect them. This review summarizes scientific instrumental techniques that have resulted

from this work. Instruments must necessarily be our “eyes” and “hands” as we attempt to identify and quantify biosignatures on Mars.

Scientific devices that can be applied in astrobiology include mass spectrometers and electromagnetic-spectrum-based spectrometers,

redox potential indicators, circular dichroism polarimeters, in situ nucleic acid sequencers, life isolation/cultivation systems, and imagers.

These devices and how to interpret the data they collect have been tested in Mars-analog extreme environments on Earth to validate

their practicality on Mars. To anticipate the challenges of instrumental detection of biosignatures through the full evolutionary history of

Mars, Terrestrial Mars analogs are divided into four major categories according to their similarities to different Martian geological periods

(the Early−Middle Noachian Period, the Late Noachian−Early Hesperian Period, the Late Hesperian−Early Amazonian Period, and the

Middle−Late Amazonian Period). Future missions are suggested that would focus more intensively on Mars’ Southern Hemisphere, once

landing issues there are solved by advances in spacecraft engineering, since exploration of these early terrains will permit investigations

covering a wider continuum of the shifting habitability of Mars through its geological history. Finally, this paper reviews practical

applications of the range of scientific instruments listed above, based on the four categories of Mars analogs here on Earth. We review the

selection of instruments suitable for autonomous robotic rover tests in these Mars analogs. From considerations of engineering efficiency,

a Mars rover ought to be equipped with as few instrument assemblies as possible. Therefore, once candidate landing regions on Mars are

defined, portable suites of instruments should be smartly devised on the basis of the known geological, geochemical, geomorphological,

and chronological characteristics of each Martian landing region. Of course, if Mars sample-return missions are successful, such samples

will allow experiments in laboratories on Earth that can be far more comprehensive and affordable than is likely to be practicable on Mars.

To exclude false positive and false negative conclusions in the search for extraterrestrial life, multiple diverse and complementary

analytical techniques must be combined, replicated, and carefully interpreted. The question of whether signatures of life can be detected

on Mars is of the greatest importance. Answering that question is extremely challenging but appears to have become manageable.

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