Journal of the American Chemical Society最新文献_第8页

Transient Salt-Bridge-Based Supramolecular Polymers: Experiments and Theory 瞬态盐桥基超分子聚合物：实验与理论

IF 15 1区化学 Q1 CHEMISTRY, MULTIDISCIPLINARY

Journal of the American Chemical Society

Pub Date : 2026-02-04 DOI: 10.1021/jacs.5c22087

Gabriele Melchiorre,Matteo Valentini,Francesco Ranieri,Davide Cantiello,Roberta Cacciapaglia,Laura Baldini,Gianfranco Ercolani,Stefano Di Stefano

The smooth decarboxylation under basic conditions of activated carboxylic acids (ACAs) is exploited to achieve a transient supramolecular polymer based on hydrogen bonds reinforced by electrostatic interactions. In particular, it is proved that when the aliphatic α,ω-diamine 3, namely, 1,8-diamino-3,6-dioxaoctane, reacts with an equimolar amount of the activated dicarboxylic acid 1H2, i.e., a difunctional derivative of 2-cyano-2-phenylpropanoic acid, a supramolecular polymer of the kind −AB─BA─AB– is immediately formed in chloroform solution. The A─A and B─B monomers are held together by salt bridges (hydrogen bonds reinforced by electrostatic interactions) between ammonium and carboxylate functions. The larger the concentration of the added materials, the higher the polymerization degree (DP) of the polymer. Under the given experimental protocol, such a polymer disaggregates over time due to decarboxylation, and at the end of the process, only diamine 3 and waste product 4, which cannot interact with one another anymore, remain in the solutions. DOSY spectra recorded at different reaction times definitely demonstrate the phenomenology described above. The trend of the degree of polymerization as a function of monomer concentration has been clarified in the light of the ring–chain equilibrium theory. The application of the theory enables the accurate evaluation of the distribution of linear and cyclic oligomers as well as the critical concentration, ccrit, above which polymerization rapidly becomes more extensive due to the saturation of macrocyclic species. Notably, the ACA is not used just as a stimulus for a dissipative system, but as one of its structural components.

利用活性羧酸（ACAs）在基本条件下的平滑脱羧，获得了一种基于静电相互作用增强的氢键的瞬态超分子聚合物。特别是，当脂肪族α，ω-二胺3，即1,8-二氨基-3,6-二氧杂辛烷与等摩尔量的活化二羧酸1H2，即2-氰基-2-苯基丙烷酸的双官能衍生物反应时，在氯仿溶液中立即生成−AB─BA─AB -类超分子聚合物。A─A和B─B单体通过盐桥（通过静电相互作用增强的氢键）在铵和羧酸盐功能之间结合在一起。添加材料的浓度越大，聚合物的聚合度（DP）越高。在给定的实验方案下，这种聚合物随着时间的推移由于脱羧而分解，在这个过程的最后，只有二胺3和废物4，它们不能再相互作用，留在溶液中。在不同反应时间记录的DOSY光谱明确地证明了上述现象。根据环链平衡理论，阐明了聚合度随单体浓度的变化趋势。该理论的应用能够准确地评估线性和环状低聚物的分布以及临界浓度，crcrs，在此之上，由于大环物种的饱和，聚合迅速变得更加广泛。值得注意的是，ACA不仅被用作耗散系统的刺激因素，而且被用作耗散系统的结构性组成部分之一。

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引用次数: 0

Synthesis of the Double Infinite-Layer Ni(I) Phase La3Ni2O5F via Sequential Topochemical Reactions 顺序拓扑化学反应合成双无限层Ni(I)相La3Ni2O5F

IF 15 1区化学 Q1 CHEMISTRY, MULTIDISCIPLINARY

Journal of the American Chemical Society

Pub Date : 2026-02-04 DOI: 10.1021/jacs.5c16740

Romain Wernert,Robert D. Smyth,Michael A. Hayward

Fluorination of the n = 2 Ruddlesden–Popper oxide, La3Ni2O7, with polyvinylidene fluoride yields La3Ni2O5F4, a phase in which fluoride ions have been inserted into interstitial sites in the Ruddlesden–Popper framework and also exchanged with the oxide ions residing on apical anion sites. Reaction with LiH at 190 °C reduces La3Ni2O5F4 by extracting interstitial fluoride ions. The resulting phase, La3Ni2O5F3, adopts a structure described in space group Pbcm in which the fluoride ions in the half-filled interstitial layer are arranged in chains parallel to the y-axis, and the NiO5F octahedra adopt an a–a–c+/–(a–a–)c+ tilting pattern. Further reduction with LiH at 250 °C converts La3Ni2O5F3 into La3Ni2O5F, a Ni1+ phase which adopts a T′-structure consisting of double infinite-sheets of apex linked NiO4 squares, stacked with LaOF fluorite-type layers. Magnetization and neutron diffraction data indicate La3Ni2O5F3 adopts an antiferromagnetically ordered state below TN = 225 K, while magnetization data from La3Ni2O5F exhibit a broad maximum centered at 75 K, suggestive of antiferromagnetic order.

n = 2 Ruddlesden-Popper氧化物La3Ni2O7与聚偏氟乙烯氟化反应生成La3Ni2O5F4，其中氟离子被插入Ruddlesden-Popper骨架的间隙位置，并与位于顶端阴离子位置的氧化物离子交换。与LiH在190℃下反应，通过提取间隙氟离子还原La3Ni2O5F4。所得相La3Ni2O5F3采用Pbcm空间基描述的结构，其中半填充的间隙层中的氟离子呈平行于y轴的链排列，NiO5F八面体呈a -a - c+/ - (a -a -)c+倾斜模式。在250℃下用LiH进一步还原，La3Ni2O5F3转化为La3Ni2O5F，这是一种Ni1+相，采用T '型结构，由双无限大的顶端连接的NiO4方形片组成，并堆叠有LaOF萤石型层。磁化和中子衍射数据表明，La3Ni2O5F3在TN = 225 K以下为反铁磁有序态，而La3Ni2O5F的磁化数据显示，在75 K处，La3Ni2O5F3为反铁磁有序态。

引用次数: 0

Proton-Fluid Preintercalation Topochemistry for High-Rate Capacity and Ultralow-Temperature Proton Storage. 高速容量和超低温质子存储的质子流体预插层拓扑化学。

IF 15.6 1区化学 Q1 CHEMISTRY, MULTIDISCIPLINARY

Journal of the American Chemical Society

Pub Date : 2026-02-04 DOI: 10.1021/jacs.5c21246

Tiezhu Xu, Tengyu Yao, Yuxuan Zhao, Zhenming Xu, Zhenhui Liu, Duo Chen, Kongjun Zhu, Laifa Shen

Fundamental limitations in structural reversibility and electrochemical performance have rendered anode materials a critical bottleneck for proton batteries and capacitors. While the rational design of intrinsic properties for metal oxides offers a promising route for advanced proton storage, the simultaneous realization of high-power and low-temperature operability remains a grand challenge. We show that topochemical preintercalation of protons and confined lattice water in hydrated molybdenum bronze modifies host lattice rearrangement and enables ultrafast proton-coupled electron transfer. Ion-fluid cointercalation mediates electrochemical reaction pathways to an unconventional three-proton insertion mechanism, enabling a state-of-the-art specific capacity of 407 mAh g^-1, ultrahigh-rate capability exceeding 1000 C (500 A g^-1), and ultralow-temperature adaptability (194.2 mAh g^-1 at -80 °C). Comprehensive in situ crystal and interface evolution methods and theoretical calculations reveal a highly reversible and homogeneous protonation mechanism and enhanced interfacial transport, suppressing heterogeneous and unstable reaction kinetics of pristine MoO₃. The hybrid proton capacitor with such a molybdenum bronze anode shows an unprecedented ultrahigh-power and ultralow-temperature performance, with excellent stability for over 2000 cycles at -80 °C. This work highlights physicochemical insights on preintercalation topochemistry in modulating charge carrier-host interactions and provides electrode design principles for high-rate and low-temperature nonmetallic ion storage.

结构可逆性和电化学性能的基本限制使阳极材料成为质子电池和电容器的关键瓶颈。虽然合理设计金属氧化物的固有性质为先进的质子存储提供了一条有希望的途径，但同时实现高功率和低温可操作性仍然是一个巨大的挑战。我们发现质子和约束晶格水在水合钼青铜中的拓扑化学预插修饰了主体晶格重排，并实现了超快的质子耦合电子转移。离子流体共插层将电化学反应途径转化为非常规的三质子插入机制，可实现407 mAh g-1的最先进比容量，超过1000℃（500 a g-1）的超高倍率容量，以及超低温适应性（-80℃时194.2 mAh g-1）。综合原位晶体和界面演化方法和理论计算揭示了一种高度可逆和均相的质子化机制，增强了界面传输，抑制了原始MoO3的非均相和不稳定反应动力学。采用这种钼青铜阳极的混合质子电容器表现出前所未有的超高功率和超低温性能，在-80℃下具有超过2000次循环的优异稳定性。这项工作强调了调制电荷载流子-宿主相互作用的插层前拓扑化学的物理化学见解，并为高速率和低温非金属离子存储提供了电极设计原则。

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引用次数: 0

Oxidation of a Dihydrophenazine Molecular Wire Attenuates Molecular Conductance 二氢非那嗪分子线的氧化降低了分子电导

IF 15 1区化学 Q1 CHEMISTRY, MULTIDISCIPLINARY

Journal of the American Chemical Society

Pub Date : 2026-02-04 DOI: 10.1021/jacs.5c18249

Moritz Nau,Raka Ahmed,Susanne Leitherer,Gemma C. Solomon,Rainer F. Winter

The concept of aromaticity is one of the most fundamental principles for understanding the properties and reactivities of organic molecules. However, in molecular electronics research, it has been shown that aromaticity is not necessarily advantageous for electron transmission across electrode-molecule-electrode junctions. In this work, we introduce formally antiaromatic, yet planar N,N’-disubstituted dihydrophenazines as a compelling building block for exploring molecular conductance properties beyond the scope of classical aromatic molecules and compare anchor group-modified dihydrophenazines and structurally closely related anthracenes. We find that molecular conductance increases by 1.5 orders of magnitude from aromatic anthracenes to their phenazine congeners, where the central ring attains partially antiaromatic character. Oxidation of the dihydrophenazine core results accordingly in conductance attenuation.

芳香性的概念是理解有机分子性质和反应性的最基本原理之一。然而，在分子电子学研究中，已经表明芳香性并不一定有利于电子在电极-分子-电极结之间的传输。在这项工作中，我们引入了形式上的反芳香族，但平面的N，N ' -二取代双氢非那嗪作为探索经典芳香族分子范围之外的分子电导特性的令人瞩目的构建块，并比较了锚基修饰的双氢非那嗪和结构上密切相关的蒽类。我们发现，从芳香蒽到它们的非那嗪同系物，分子电导增加了1.5个数量级，其中中心环达到部分反芳香特征。二氢非那嗪芯的氧化导致相应的电导衰减。

引用次数: 0

Assembling Ternary Dead-End Complex for Covalent Trapping of Protein Lysine Methyltransferases 组装三元终端复合物用于蛋白质赖氨酸甲基转移酶的共价捕获

IF 15 1区化学 Q1 CHEMISTRY, MULTIDISCIPLINARY

Journal of the American Chemical Society

Pub Date : 2026-02-04 DOI: 10.1021/jacs.5c14571

Yu Zong,Nawei Zhang,Jason Lin,Zhizhong Li,Yuqiao Zou,Rohit Chaudhuri,Minkui Luo

Protein lysine methylation is a distinct class of post-translational modifications because it minimally alters the size and positive charge of the lysine side chain. In cellular contexts, the human genome encodes over 60 protein lysine methyltransferases (PKMTs), with the S-adenosyl-l-methionine (SAM) cofactor as the methyl donor, to modify thousands of lysine sites on histones and nonhistone targets in a highly orchestrated manner. The biological roles of protein lysine methylation are increasingly implicated in epigenetic regulation to define diverse cell fates, and their dysregulation is frequently associated with developmental abnormalities and various aspects of cancerous malignancy. However, it has been challenging to annotate the multiple upstream methyltransferase(s) in parallel from known methyllysine marks in the context of over 60 PKMT candidates with redundant and cell-type-dependent activities. We therefore envisioned the technology of Covalent Trapping of Protein Lysine Methyltransferases (CTPM) by assembling the ternary dead-end complex of PKMTs with substrate-cofactor surrogates. With SET-domain-containing PKMTs, the norleucine(Nle)-SAM pair was shown to be a robust structural motif to form such dead-end complexes, likely via harnessing the common feature of the transition state of PKMT-catalyzed lysine methylation. Our CTPM peptidic probes contain the Nle warhead in the place of substrate lysine, the photo-cross-linking residue in proximity of Nle, and the terminal biotin anchor for target enrichment. These CTPM probes, upon pairing with the SAM cofactor, show high efficiency in trapping the upstream PKMTs of the cognate histone and nonhistone substrates.

蛋白质赖氨酸甲基化是一类独特的翻译后修饰，因为它可以最小程度地改变赖氨酸侧链的大小和正电荷。在细胞环境中，人类基因组编码超过60种蛋白质赖氨酸甲基转移酶（pkmt），以s -腺苷-l-蛋氨酸（SAM）辅助因子作为甲基供体，以高度协调的方式修饰组蛋白和非组蛋白靶点上的数千个赖氨酸位点。蛋白质赖氨酸甲基化的生物学作用越来越多地与表观遗传调控有关，以确定不同的细胞命运，其失调通常与发育异常和恶性肿瘤的各个方面有关。然而，在超过60个具有冗余和细胞类型依赖活性的PKMT候选基因的背景下，从已知的甲基赖氨酸标记平行地注释多个上游甲基转移酶(s)一直具有挑战性。因此，我们设想了蛋白质赖氨酸甲基转移酶（CTPM）的共价捕获技术，通过组装pkmt的三元死端复合物和底物辅助因子替代物。对于含有set结构域的pkmt，去甲亮氨酸(Nle)-SAM对被证明是形成这种死端复合物的强大结构基元，可能是通过利用pkmt催化赖氨酸甲基化过渡状态的共同特征。我们的CTPM肽探针包含Nle弹头代替底物赖氨酸，Nle附近的光交联残基，以及用于靶富集的末端生物素锚点。这些CTPM探针与SAM辅助因子配对后，在捕获同源组蛋白和非组蛋白底物的上游pkmt方面表现出高效率。

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引用次数: 0

Discovery of a Human Metabolite That Mimics the Bacterial Quorum-Sensing Autoinducer AI-2 人类代谢物的发现，模仿细菌群体感应自诱导物AI-2

IF 15 1区化学 Q1 CHEMISTRY, MULTIDISCIPLINARY

Journal of the American Chemical Society

Pub Date : 2026-02-04 DOI: 10.1021/jacs.5c18527

Emilee E. Shine,Julie S. Valastyan,Vanessa Y. Ying,Jonathan Z. Huang,Mohammad R. Seyedsayamdost,Bonnie L. Bassler

Bacteria use small molecules to orchestrate collective behaviors in a process called quorum sensing (QS), which relies on the production, release, and group-wide detection of extracellular signal molecules referred to as autoinducers. One QS autoinducer, termed AI-2, is broadly used for interspecies bacterial communication, including in the mammalian gut. AI-2 consists of a family of interconverting compounds and adducts originating from 4,5-dihydroxy-2,3-pentanedione. This complex speciation, coupled with the inherent instability of AI-2 congeners, have complicated isolation efforts. It has been known that mammalian epithelial cells produce an AI-2 mimic to which bacteria respond. However, the identity of the AI-2 mimic has remained elusive, presumably due to its instability, similar to that of known AI-2 compounds. Here, we developed a reactivity-based metabolomics approach to capture and identify a mammalian AI-2 mimic. Using a chemical strategy targeted at the α-diketone moiety of known AI-2s, we identify the unusual sugar l-xylosone, as well as the related metabolite l-xylulose, as AI-2 mimics. While l-xylulose is a common and naturally occurring sugar known in human metabolism, l-xylosone is a rare and highly reactive oxidation product. We established a facile synthetic route to access pure enantiomers of xylosone and confirmed that, like AI-2, the l-configuration is required for recognition by the bacterial AI-2 receptor, LuxP, whereas d-xylosone is inactive. l-xylosone is new to the human metabolome, suggesting that other chemically reactive small molecules that mediate host–microbe interactions await discovery. The identification of l-xylosone expands the AI-2 family of molecules and adds a new word to the lexicon of host–bacterial interactions.

细菌在称为群体感应（QS）的过程中使用小分子来协调集体行为，这依赖于被称为自诱导剂的细胞外信号分子的产生、释放和群体范围内的检测。一种称为AI-2的QS自诱导剂广泛用于种间细菌交流，包括在哺乳动物肠道中。AI-2由一系列源自4,5-二羟基-2,3-戊二酮的相互转化化合物和加合物组成。这种复杂的物种形成，加上AI-2同系物固有的不稳定性，使分离工作变得复杂。已知哺乳动物上皮细胞产生一种AI-2模拟物，细菌对其有反应。然而，人工智能-2模拟物的身份仍然难以捉摸，大概是由于它的不稳定性，类似于已知的人工智能-2化合物。在这里，我们开发了一种基于反应性的代谢组学方法来捕获和鉴定哺乳动物AI-2模拟物。利用针对已知AI-2 α-二酮部分的化学策略，我们确定了不寻常的糖l-木糖酮，以及相关的代谢物l-木糖糖，作为AI-2的模拟物。虽然l-木糖糖是一种常见的天然存在的糖，已知在人体代谢中，l-木糖酮是一种罕见的和高度活跃的氧化产物。我们建立了一种简单的合成途径来获得纯木糖酮对映体，并证实，与AI-2一样，细菌AI-2受体LuxP需要l构型才能识别，而d-木糖酮则是无活性的。l-木糖酮是人类代谢组的新发现，这表明介导宿主-微生物相互作用的其他化学反应性小分子有待发现。l-木糖酮的鉴定扩大了AI-2分子家族，并为宿主-细菌相互作用的词典增加了一个新词。

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引用次数: 0

De Novo Labile C-N Bonds Enable Dynamic Covalent Chemistry and Reversible Bioimaging. 新的不稳定C-N键实现动态共价化学和可逆生物成像。

IF 15.6 1区化学 Q1 CHEMISTRY, MULTIDISCIPLINARY

Journal of the American Chemical Society

Pub Date : 2026-02-04 DOI: 10.1021/jacs.5c16437

Chenming Chan, Yating Wang, Jingjing Wan, Yujie Han, Zhaoli Xue, Yang Tian, Qi-Wei Zhang

Dynamic covalent bonds (DCBs) enable reversible bond formation/cleavage, offering exciting possibilities for smart and adaptive materials, yet challenges such as slow kinetics and stringent conditions required for the reverse reaction currently hinder their broader use. We present a novel C-N σ-bond with exceptional reversibility and ultrafast kinetics (t_1/2 = 200 ms) across diverse primary aliphatic amine substrates, occurring spontaneously under ambient conditions without catalysts or external energy input, which is enabled by remarkably low activation barriers and near-equilibrium energetics. We showcase this transformative DCB's versatility in reversible gas-fixation, programmable transamination, and construct the first reversible chemical probes for real-time quantitative tracking of spatiotemporal histamine dynamics in live cells and in vivo within the brain under inflammatory pathology. This work redefines C-N σ-bonds as dynamic linkages, opening avenues for innovation in organic chemistry, adaptive materials, and dynamic biosystems.

动态共价键（DCBs）能够实现可逆键的形成/裂解，为智能和自适应材料提供了令人兴奋的可能性，但目前逆反应所需的缓慢动力学和严格条件等挑战阻碍了它们的广泛应用。我们提出了一种新的C-N σ-键，具有优异的可逆性和超快的动力学（t1/2 = 200 ms），跨越多种初级脂肪胺底物，在环境条件下自发发生，无需催化剂或外部能量输入，这是由非常低的激活障碍和接近平衡的能量学实现的。我们展示了这种变革性DCB在可逆气体固定、可编程转氨化方面的多功能性，并构建了第一个可逆化学探针，用于实时定量跟踪活细胞和炎症病理下大脑内的时空组胺动态。这项工作将C-N σ-键重新定义为动态键，为有机化学、自适应材料和动态生物系统的创新开辟了道路。

引用次数: 0

Axis-Dependent Conduction Polarity: Design Principles and High-Throughput Discovery of Transverse Thermoelectrics 轴相关的传导极性：设计原则和横向热电的高通量发现

IF 15 1区化学 Q1 CHEMISTRY, MULTIDISCIPLINARY

Journal of the American Chemical Society

Pub Date : 2026-02-04 DOI: 10.1021/jacs.5c22733

Zan Yang,Xinyi He,Hidetomo Usui,Toshio Kamiya,Takayoshi Katase

Some semiconductor materials exhibit axis-dependent conduction polarity (ADCP), where carrier transport is dominated by electrons along one crystallographic axis and holes along another. This unconventional transport behavior enables transverse thermoelectricity and other functionalities that are inaccessible in conventional isotropic/unipolar semiconductors. However, only a few ADCP materials have been identified, largely because the underlying electronic design principles have remained unclear. Here, we establish a quantitative framework that defines the electronic conditions required for ADCP to emerge and remain robust. Using a minimal two-band tight-binding model, we clarify that ADCP requires two key electronic conditions: a sufficiently small band gap that enables simultaneous electron–hole transport and strong anisotropy in carrier effective masses that causes their transport contributions to differ between axes. These parameters define a chemical-potential window in which axis-resolved Seebeck coefficients take opposite signs, identifying narrow-gap semiconductors and semimetals with anisotropic band edges as prime ADCP candidates. Guided by these criteria, we conduct a first-principles screening of 4282 anisotropic narrow-gap semiconductors and metals and identify 361 ADCP materials, which are predominantly found among chalcogenides, pnictides, and tetrel-based compounds, including 57 potential transverse thermoelectrics. Analysis of two representative materials, AlReGe and ZrSe3, reveals that ADCP originates from anisotropic band-edge states derived from low-dimensional bonding networks, resulting in spatially separated electron and hole transport on different crystal sublattices. These results provide chemically intuitive design rules for ADCP materials and establish a comprehensive data set for accelerating the development of transverse thermoelectrics and other next-generation electronic devices.

一些半导体材料表现出轴相关的传导极性（ADCP），其中载流子输运主要是电子沿一个晶体轴和空穴沿另一个晶体轴。这种非常规的输运行为实现了传统各向同性/单极半导体无法实现的横向热电和其他功能。然而，只有少数ADCP材料已经确定，很大程度上是因为潜在的电子设计原则仍然不清楚。在这里，我们建立了一个定量框架，定义了ADCP出现和保持稳健所需的电子条件。使用最小的两波段紧密结合模型，我们阐明了ADCP需要两个关键的电子条件：足够小的带隙，能够同时进行电子-空穴输运；载流子有效质量的强各向异性，导致它们在不同轴之间的输运贡献不同。这些参数定义了一个化学势窗口，其中轴分辨塞贝克系数取相反的符号，确定具有各向异性带边缘的窄间隙半导体和半金属作为主要的ADCP候选者。在这些标准的指导下，我们对4282种各向异性窄间隙半导体和金属进行了第一性原理筛选，并鉴定出361种ADCP材料，这些材料主要存在于硫族化合物、羟基化合物和四萜化合物中，包括57种潜在的横向热电材料。对两种具有代表性的材料AlReGe和ZrSe3的分析表明，ADCP起源于低维键合网络的各向异性带边态，导致不同晶体亚晶格上的电子和空穴输运在空间上分离。这些结果为ADCP材料提供了化学上直观的设计规则，并为加速横向热电器件和其他下一代电子器件的开发建立了全面的数据集。

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引用次数: 0

Electrochemical CO2 Reduction in the Presence of SO2 Impurities on a Nitrogen-Doped Carbon Electrocatalyst 氮掺杂碳电催化剂上SO2杂质存在下的电化学CO2还原

IF 15 1区化学 Q1 CHEMISTRY, MULTIDISCIPLINARY

Journal of the American Chemical Society

Pub Date : 2026-02-04 DOI: 10.1021/jacs.5c11790

Shilong Fu,Bowen Sha,Asvin Sajeev,Ming Li,Thijs J. H. Vlugt,Othonas A. Moultos,Wiebren de Jong,Ruud Kortlever

Electrochemical CO2 reduction to CO offers a sustainable route for converting CO2 into value-added chemicals and fuels. However, CO2 streams derived from industrial sources often contain SO2 impurities that severely poison conventional metal-based catalysts. Here, we report a nitrogen-doped carbon catalyst that exhibits pronounced tolerance and stability for CO2-to-CO conversion in the presence of SO2 (100–10,000 ppm). The catalyst maintains over 90% Faradaic efficiency toward CO during 8 h of electrolysis at −1.0 V vs RHE with 100 ppm of SO2, whereas Ag foil electrodes undergo rapid deactivation. Density functional theory calculations combined with surface analyses indicate that weak SO2 adsorption and the absence of stable sulfur accumulation on nitrogen-doped carbon strengthen its resistance to impurity-induced deactivation, in contrast to Ag catalysts that form Ag2S. Gas-fed tests in a membrane electrode assembly (MEA) electrolyzer further confirm that nitrogen-doped carbon sustains high CO selectivity at elevated current densities, while Ag nanoparticles suffer irreversible sulfur poisoning. These results demonstrate that nitrogen-doped carbon is intrinsically resistant to SO2-induced deactivation and highlight its potential as a robust catalyst for CO2 electroreduction under impurity-containing conditions.

电化学CO2还原为CO提供了将CO2转化为增值化学品和燃料的可持续途径。然而，来自工业来源的二氧化碳流通常含有SO2杂质，严重毒害传统的金属基催化剂。在这里，我们报道了一种氮掺杂碳催化剂，在SO2 （100-10,000 ppm）存在下，对co2到co的转化表现出明显的耐受性和稳定性。在−1.0 V vs RHE和100 ppm SO2条件下电解8 h，催化剂对CO的法拉第效率保持在90%以上，而银箔电极则快速失活。密度泛函理论计算结合表面分析表明，与形成Ag2S的Ag催化剂相比，氮掺杂碳对SO2的弱吸附和不存在稳定的硫积累增强了其对杂质诱导失活的抗性。在膜电极组件（MEA）电解槽中的气供测试进一步证实，氮掺杂碳在高电流密度下保持高CO选择性，而银纳米颗粒则遭受不可逆的硫中毒。这些结果表明，氮掺杂碳本质上抵抗二氧化硫诱导的失活，并突出了其作为含杂质条件下CO2电还原催化剂的潜力。

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引用次数: 0

Thermo-Bistable Red and Sensitized Near-Infrared Photoswitches 热双稳红色和敏化近红外光开关

IF 15 1区化学 Q1 CHEMISTRY, MULTIDISCIPLINARY

Journal of the American Chemical Society

Pub Date : 2026-02-04 DOI: 10.1021/jacs.5c20020

Zhiwei Zhang,Zhubin Hu,Lei Huang,Huichao Guo,Jinghong Dai,Long Deng,Guining Gong,Tong Xia,Ruijia Sun,Botao Ji,Wei-Hong Zhu,Junji Zhang,He Tian

Molecular photoswitching in the red and near-infrared (NIR) region is highly sought after for applications in biological systems, optoelectronic devices, and functional materials where low-energy light minimizes photodamage and enables deep-tissue penetration. However, developing photoswitches that simultaneously achieve long-wavelength responsiveness with robust thermal bistability and high quantum efficiency remains a formidable challenge. Here, we report an intrinsic thermo-bistable, red-light-responsive (605 nm/730 nm) photochromic motif based on a perylene bisimide (PBI) scaffold, which further enables an unprecedented sensitized NIR (808 nm/730 nm) photoisomerization through a triplet pathway. Rational side-chain engineering with aryl substituents of distinct aromaticity and electronic character finely tunes the transition-state energy barrier (ΔG‡ = 45.07 kcal mol–1), leading to exceptional thermal stability and a long-lived closed isomer. Further molecular engineering of PBI-based photoswitches also delivers high photoisomerization quantum yield, bright fluorescence, and near-quantitative photoconversion efficiency. This work provides a new photochromic motif that boosts the overall photochemical/thermal performances of molecular photoswitching at the red-light end, thereby enriching the structural and functional landscape of a high-performance photoswitching system. Demonstrations in dynamic cell-membrane imaging further highlight the potential of these PBI-based photoswitches as powerful photochemical platforms for advanced biomedical and optoelectronic applications.

红色和近红外（NIR）区域的分子光电开关在生物系统、光电子器件和功能材料中的应用备受追捧，在这些应用中，低能量光可以最大限度地减少光损伤并实现深层组织穿透。然而，开发同时具有强大的热双稳定性和高量子效率的长波长响应性的光开关仍然是一个艰巨的挑战。在这里，我们报道了一个基于苝二酰亚胺（PBI）支架的固有热双稳态、红光响应（605 nm/730 nm）光致变色基序，该基序进一步通过三重态途径实现了前所未有的近红外（808 nm/730 nm）光异构化。具有不同芳香性和电子特征的芳基取代基的合理侧链工程精细地调节了过渡态能垒（ΔG‡= 45.07 kcal mol-1），从而获得了优异的热稳定性和长寿命的封闭异构体。基于pbi的光开关的进一步分子工程也提供了高光异构量子产率，明亮的荧光和近定量的光转换效率。这项工作提供了一个新的光致变色基序，提高了分子光开关在红光端的整体光化学/热性能，从而丰富了高性能光开关系统的结构和功能景观。动态细胞膜成像的演示进一步突出了这些基于pbi的光开关作为先进生物医学和光电子应用的强大光化学平台的潜力。

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引用次数: 0