Materials Today Physics最新文献_第3页

Wavelength-dependent photoresponse changes in graphene photodetectors induced by perovskite quantum dots 钙钛矿量子点诱导石墨烯光电探测器的波长相关光响应变化

IF 9.7 2区材料科学 Q1 MATERIALS SCIENCE, MULTIDISCIPLINARY

Materials Today Physics

Pub Date : 2026-02-01 DOI: 10.1016/j.mtphys.2026.102031

Young Jun Noh , Minjin Kim , Gi Hun Nam , Akash Gupta , Kootak Hong , Dongguen Shin , Doojin Lee , Yong Il Park , Sang Hyun Lee

Understanding the mechanisms underlying photocurrent generation in graphene-based photodetectors is essential for enhancing their spectral selectivity and response stability. Therefore, this study aims to systematically investigate and compare the photoresponse mechanisms of pristine monolayer graphene and CsPbBr₃ quantum dot (QD)-sensitized graphene heterostructures under 450 nm and 525 nm laser irradiation. Pristine graphene exhibits a wavelength-dependent photoresponse, with a pronounced negative photocurrent (NPC) under 450 nm irradiation due to photodesorption of p-type dopants and defect-assisted photoionization from the SiO₂ substrate. Under 525 nm irradiation, where photon energy is insufficient to activate surface and substrate mechanisms, graphene exhibited an unstable positive photocurrent (PPC) driven by weak photoconduction. In contrast, the CsPbBr₃/graphene heterostructure consistently exhibits strong and stable PPC at wavelengths. The integration of CsPbBr₃ QD enables efficient photocarrier generation and transfer to the graphene channel, overriding parasitic NPC pathways and stabilizing the overall photoresponse. Time-resolved measurements reveals significantly faster rise and fall times in the heterostructure, confirming a transition from slow surface-mediated processes to rapid photoconductive dynamics. This comparative study elucidates how intrinsic graphene properties, substrate interactions, and heterojunction effects collectively drive the photocurrent polarity and enhance performance in hybrid 2D/0D photodetectors.

了解石墨烯基光电探测器中光电流产生的机制对于提高其光谱选择性和响应稳定性至关重要。因此，本研究旨在系统研究和比较原始单层石墨烯和CsPbBr3量子点（QD）敏化石墨烯异质结构在450 nm和525 nm激光照射下的光响应机制。原始石墨烯表现出波长依赖的光响应，由于p型掺杂剂的光解吸和SiO2衬底的缺陷辅助光电离，在450 nm照射下具有明显的负光电流（NPC）。在525 nm辐照下，光子能量不足以激活表面和衬底机制，石墨烯表现出不稳定的正光电流（PPC），由弱光导驱动。相比之下，CsPbBr3/石墨烯异质结构在波长上始终表现出强大而稳定的PPC。CsPbBr3 QD的集成实现了高效的光载流子生成和转移到石墨烯通道，覆盖了寄生NPC途径并稳定了整体光响应。时间分辨测量显示异质结构的上升和下降时间明显更快，证实了从缓慢的表面介导过程到快速光导动力学的转变。这项比较研究阐明了石墨烯的固有特性、衬底相互作用和异质结效应如何共同驱动光电流极性，并提高了混合2D/0D光电探测器的性能。

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引用次数: 0

Optoelectronic logic gates and chaotic encryption optical communication enabled by dual-band optical response in a-Ga2O3/Cr2O3 heterostructures a-Ga2O3/Cr2O3异质结构中双带光响应实现光电逻辑门和混沌加密光通信

IF 9.7 2区材料科学 Q1 MATERIALS SCIENCE, MULTIDISCIPLINARY

Materials Today Physics

Pub Date : 2026-02-01 DOI: 10.1016/j.mtphys.2026.102032

Quancai Yue , Lijuan Ye , Lai Yuan, Guoping Qin, Di Pang, Yan Tang, Honglin Li, Hong Zhang, Wanjun Li

Self-powered bipolar photodetectors (PDs) have garnered significant attention for their potential in optoelectronic logic gates (OELGs) and secure optical communication systems, owing to their extremely low power consumption and cost-effectiveness. However, conventional unipolar PDs are constrained by functional rigidity and their reliance on passive decoding circuits. In this study, a self-powered bipolar photoelectrochemical detector (PEC-PD) is presented with a wavelength-dependent photoresponse in electrolytes, based on an amorphous gallium oxide/chromium oxide (a-Ga₂O₃/Cr₂O₃) p–n heterojunction. This distinctive behavior arises from variations in the competitive dynamics between interfacial redox reactions and photogenerated carrier transport at the semiconductor/electrolyte interface under short-wave ultraviolet (UV-C) and long-wave ultraviolet (UV-A) irradiation. The device exhibits a positive photocurrent response time of 82.1/91.2 ms under 254 nm illumination and a negative photocurrent response time of 9.1/13.6 ms under 380 nm without an external power supply. Utilizing this tunable photoresponse, five fundamental Boolean logic operations—“OR”, “AND”, “NOR”, “NOT”, and “NAND”—are demonstrated by tailoring the illumination at specific wavelengths. Furthermore, the distinct bipolar photocurrent behaviors enable encrypted optical communication within a single photoelectrode architecture. This study advances the understanding of carrier dynamics manipulation and provides a solid foundation for the development of multi-functional OELGs and secure optical communication systems.

由于其极低的功耗和成本效益，自供电双极光电探测器（pd）因其在光电逻辑门（OELGs）和安全光通信系统中的潜力而受到广泛关注。然而，传统的单极pd受到功能刚性和对无源解码电路的依赖的限制。在这项研究中，一种基于非晶氧化镓/氧化铬（a- ga2o3 /Cr2O3） p-n异质结的自供电双极光电电化学探测器（PEC-PD）在电解质中具有波长依赖的光响应。这种独特的行为源于在短波紫外线（UV-C）和长波紫外线（UV-A）照射下半导体/电解质界面氧化还原反应和光产生的载流子输运之间竞争动力学的变化。该器件在254 nm光照下的正光电流响应时间为82.1/91.2 ms，在没有外部电源的情况下，在380 nm光照下的负光电流响应时间为9.1/13.6 ms。利用这种可调谐的光响应，五种基本的布尔逻辑运算-“或”，“与”，“非”，“非”和“NAND”-通过剪裁特定波长的照明来演示。此外，独特的双极光电流行为使单个光电极结构内的加密光通信成为可能。该研究促进了对载流子动力学操纵的理解，为开发多功能oelg和安全光通信系统提供了坚实的基础。

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引用次数: 0

Supramolecular polymer-guided functionalization of rhenium diselenide nanosheets: Hierarchical Co-assembly and advanced performance 二硒化铼纳米片的超分子聚合物引导功能化：分层共组装和先进性能

IF 9.7 2区材料科学 Q1 MATERIALS SCIENCE, MULTIDISCIPLINARY

Materials Today Physics

Pub Date : 2026-02-01 DOI: 10.1016/j.mtphys.2026.102041

Tse-Hsin Lo , Ching-Hwa Ho , Wei-Tsung Chuang , Chih-Ping Chen , Chih-Chia Cheng

Rhenium diselenide (ReSe₂), a two-dimensional nanomaterial with excellent physical properties, holds potential for various applications. However, its performance and sustainability are severely limited by structural inhomogeneity, low electrical conductivity, and instability at high temperatures. We present an innovative approach to enhance its physical properties by combining ReSe₂ with an adenine-functionalized supramolecular polymer (AJ) to co-assemble a novel supramolecular composite system. Due to the strong affinity between the adenine groups in AJ and ReSe₂ crystals, AJ polymer chains securely attach to the ReSe₂ surface and self-assemble into hexagonal and lamellar nanostructures, which promotes stable exfoliation of ReSe₂ nanosheets and enhances the overall structural stability of the composites. Exfoliated ReSe₂ nanosheets exhibit many promising physical properties, including controllable layer number, uniform micron-sized thin nanosheet structures, distinct microscopic morphologies, and highly stable thermally reversible phase transitions and rheological behavior. Importantly, these composites exhibit significantly lower resistance and stable conductive performance compared to bulk ReSe₂ in electrochemical impedance and single-layer device evaluations, and enabled stable current conduction in devices. This newly developed system demonstrates the potential of supramolecular polymers to regulate the material properties of ReSe₂ and opens new opportunities for optoelectronics, semiconductors, and advanced technologies.

二硒化铼（ReSe2）是一种具有优异物理性能的二维纳米材料，具有广泛的应用前景。然而，其性能和可持续性受到结构不均匀性、低导电性和高温不稳定性的严重限制。我们提出了一种创新的方法，通过将ReSe2与腺嘌呤功能化的超分子聚合物（AJ）结合来共同组装一种新的超分子复合体系，以增强其物理性能。由于AJ和ReSe2晶体中的腺嘌呤基团之间具有很强的亲和力，AJ聚合物链可以安全地附着在ReSe2表面并自组装成六边形和片层状纳米结构，从而促进了ReSe2纳米片的稳定剥离，增强了复合材料的整体结构稳定性。剥离后的ReSe2纳米片具有许多有前途的物理性质，包括可控的层数、均匀的微米级薄纳米片结构、独特的微观形貌、高度稳定的热可逆相变和流变行为。重要的是，与本体ReSe2相比，这些复合材料在电化学阻抗和单层器件评估中表现出明显更低的电阻和稳定的导电性能，并使器件中的电流传导稳定。这个新开发的系统展示了超分子聚合物调节ReSe2材料特性的潜力，并为光电子、半导体和先进技术开辟了新的机会。

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引用次数: 0

Reversible thermal stiffening in polymers: A mini review 聚合物的可逆热硬化：综述

IF 9.7 2区材料科学 Q1 MATERIALS SCIENCE, MULTIDISCIPLINARY

Materials Today Physics

Pub Date : 2026-02-01 DOI: 10.1016/j.mtphys.2026.102042

Di Wu , Shuyue He , Wenbo Liu , Jason Y. Fang , Yue Wang

Conventional polymers lose mechanical properties at elevated temperatures, driving interest in polymers that show reversible heat-triggered stiffening. This review focuses on summarizing recent advances in smart polymer systems that exhibit reversible thermal stiffening, an unconventional property, where mechanical strength increases upon heating. Triggered temperature, stiffening factor, and response time are the three parameters for characterizing this behavior. We observed two primary material classes: polymer gels and solvent-free polymer melts, examining their design strategies, preparation methods, and underlying mechanisms. In gel systems, thermal stiffening is predominantly achieved upon lower critical solution temperature (LCST) polymer in solutions, while solvent-free polymer melts demonstrate more diverse and system-specific mechanisms. Although the material designs are distinguished, the reported thermal stiffening mechanisms can be summarized as reversible thermally triggered continuous polymer phases separation, denser polymer network, self-assembly polymer network, and particle network. To our knowledge, this article offers a comprehensive overview discussing various strategies for realizing thermal stiffening behavior in polymers. It also provides guidance for future developments in this emerging field of temperature-responsive smart polymer materials with self-enhanced performance capabilities.

传统聚合物在高温下会失去机械性能，这促使人们对具有可逆热致硬化特性的聚合物产生兴趣。这篇综述的重点是总结智能聚合物系统的最新进展，这些系统表现出可逆热硬化，这是一种非常规的特性，在加热时机械强度会增加。触发温度、强化系数和响应时间是表征这种行为的三个参数。我们观察了两种主要的材料类别：聚合物凝胶和无溶剂聚合物熔体，研究了它们的设计策略、制备方法和潜在的机制。在凝胶体系中，热硬化主要是在较低临界溶液温度（LCST）聚合物溶液中实现的，而无溶剂聚合物熔体则表现出更多样化和系统特异性的机制。虽然材料的设计是不同的，但报道的热强化机制可以概括为可逆的热触发连续聚合物相分离，更密集的聚合物网络，自组装聚合物网络和颗粒网络。据我们所知，这篇文章提供了一个全面的概述，讨论了实现聚合物热硬化行为的各种策略。它还为具有自我增强性能的温度响应智能聚合物材料这一新兴领域的未来发展提供了指导。

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引用次数: 0

Pressure and composition tuning of structural and electronic properties of the ternary chalcohalide Pb4SeBr6 三元乙醇化物Pb4SeBr6结构和电子性能的压力和组成调谐

IF 9.7 2区材料科学 Q1 MATERIALS SCIENCE, MULTIDISCIPLINARY

Materials Today Physics

Pub Date : 2026-02-01 DOI: 10.1016/j.mtphys.2026.102036

Junhui Liang , Ying Sun , Wenbo Qiu , Shuangjiang Du , Xinglong Deng , Weizhao Cai

Chalcohalides, a class of mixed-anion semiconductors featuring both chalcogenide and halide atoms, exhibit rich structural diversity and functional properties such as strong nonlinear optical responses and ferroelectricity. Although high-pressure studies have revealed dramatic electronic transformations, including metallization and superconductivity in several chalcohalides, Pb-based systems remain largely unexplored. Here, we combine high-pressure experiments with targeted chemical substitution to investigate the structural and electronic evolution of the ternary chalcohalide Pb₄SeBr₆. We show that both physical compression and Te substitution provide effective routes to electronic-structure tuning. The derivatives Pb₄Se_1-xTe_xBr₆ (x = 0.05 and 0.18) exhibit bandgap reductions of 5.3% and 8.3%, respectively, corresponding to the effect of applying ∼5.6 GPa and ∼8.6 GPa of external pressure to the parent compound. In the parent compound, compression induces a substantial redshift of the absorption edge, narrowing the bandgap by ∼64.9% at 25.2 GPa. At ∼20.0 GPa, Pb₄SeBr₆ undergoes a first-order phase transition with the noncentrosymmetric structure retained, whereas the Te substitution (x = 0.18) produces a modest upward shift of the transition pressure to ∼22 GPa. Combined high-pressure electrical transport measurements and first-principles calculations further predict a semiconductor-to-metal transition near 90 GPa. These results demonstrate that synergistically applying physical pressure and chemical substitution provides a robust strategy for engineering electronic properties in chalcohalides, offering guidance for designing next-generation functional mixed-anion materials.

硫卤化物（Chalcohalides）是一类同时具有硫系原子和卤化物原子的混合阴离子半导体，具有丰富的结构多样性和强大的非线性光学响应和铁电性等功能特性。尽管高压研究已经揭示了剧烈的电子转变，包括几种硫化物的金属化和超导性，但基于铅的系统在很大程度上仍未被探索。在这里，我们结合高压实验和靶向化学取代来研究三元乙醇化物Pb4SeBr6的结构和电子演化。我们发现物理压缩和Te取代都为电子结构调谐提供了有效的途径。衍生物Pb4Se1-xTexBr6 （x = 0.05和0.18）分别表现出5.3%和8.3%的带隙减小，对应于对母体化合物施加~ 5.6 GPa和~ 8.6 GPa的外部压力的影响。在母体化合物中，压缩引起吸收边的大量红移，在25.2 GPa时将带隙缩小了约64.9%。在~ 20.0 GPa时，Pb4SeBr6经历了一阶相变，保留了非中心对称结构，而Te取代（x = 0.18）使转变压力适度上升到~ 22 GPa。结合高压电输运测量和第一性原理计算，进一步预测了半导体到金属的转变接近90 GPa。这些结果表明，协同施加物理压力和化学替代为设计下一代功能混合阴离子材料提供了一种强大的策略。

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引用次数: 0

Phase transitions, dielectric response and lattice dynamics of dimethylammonium mixed lead halide perovskites 二甲基铵混合卤化铅钙钛矿的相变、介电响应和晶格动力学

IF 9.7 2区材料科学 Q1 MATERIALS SCIENCE, MULTIDISCIPLINARY

Materials Today Physics

Pub Date : 2026-02-01 DOI: 10.1016/j.mtphys.2026.102024

Furqanul Hassan Naqvi , Syed Bilal Junaid , Jae-Hyeon Ko , Hyun Jung Kim , Hyoungjeen Jeen , Wonhyuk Shon , Seongsu Lee , Seong Heon Kim , Yeong Uk Choi , Jong Hoon Jung

Hybrid organic–inorganic perovskites exhibit rich structural dynamics that govern their stability and optoelectronic performance. Here we map the temperature-composition phase behavior of dimethylammonium lead mixed halides, DMAPbBr_3-xCl_x with x = 0, 0.5, 1.5, 2, 2.5 and 3, by combining temperature-dependent powder X-ray diffraction, Raman and Brillouin spectroscopy, dielectric spectroscopy and differential scanning calorimetry. All compositions undergo a first-order transition between an orthorhombic (P2₁2₁2₁) low-temperature phase and a hexagonal (P6₃/mmc) high-temperature phase. The transition temperature increases monotonically with Cl content at 251, 256, 265, 283, 306, and 318 K for x = 0, 0.5, 1.5, 2, 2.5, and 3, respectively. Distinct experimental signatures include: (i) abrupt hardening/softening anomalies of low-frequency Raman modes (down to 10 cm⁻¹) associated with octahedral twists and Pb–X stretching; (ii) softening of the longitudinal acoustic phonon mode and a discontinuous jump at transition temperatures in the Brillouin spectra, evidencing elastic modulus renormalization; (iii) step-like increases in the real part of the dielectric permittivity (ε₁), reflecting increased DMA reorientational polarizability and (iv) sharp DSC endotherms that quantify latent heat and confirm the first-order character. We integrate these datasets to develop a temperature–composition phase diagram for DMAPbBr_3-xCl_x and clarify how halide substitution stiffens the lattice and strengthens hydrogen-bond network to tune the transition temperature. The results provide mechanistic insight into cation–framework coupling in DMA-based perovskites and valuable insights for optimizing their structural properties to enhance device performance.

杂化有机-无机钙钛矿表现出丰富的结构动力学，这决定了它们的稳定性和光电性能。本文通过结合温度相关的粉末x射线衍射、拉曼和布里渊光谱、介电光谱和差示扫描量热法，绘制了x = 0、0.5、1.5、2、2.5和3的二甲基铵铅混合卤化物DMAPbBr3-xClx的温度-组成相行为。所有化合物都经历了正交（P212121）低温相和六方（P63/mmc）高温相之间的一阶转变。当x分别为0、0.5、1.5、2、2.5和3时，在251、256、265、283、306和318 K时，转变温度随Cl含量的增加而单调升高。不同的实验特征包括：(i)与八面体扭曲和Pb-X拉伸相关的低频拉曼模式（低至10 cm−1）的突然硬化/软化异常；（ii）纵向声子模式的软化和布里渊光谱在转变温度处的不连续跳变，证明弹性模量重整化；（iii）介电常数实部（ε1）呈阶梯状增加，反映了DMA重定向极化率的增加；（iv）明显的DSC恒温曲线量化了潜热并证实了一阶特征。我们整合这些数据集来开发DMAPbBr3-xClx的温度-组成相图，并阐明卤化物取代如何使晶格硬化并加强氢键网络以调整转变温度。研究结果为dma钙钛矿中的阳离子-框架耦合提供了机理见解，并为优化其结构特性以提高器件性能提供了有价值的见解。

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引用次数: 0

A low-emissivity thermochromic coating for year-round window efficiency 一种全年窗效的低发射率热致变色涂层

IF 9.7 2区材料科学 Q1 MATERIALS SCIENCE, MULTIDISCIPLINARY

Materials Today Physics

Pub Date : 2026-02-01 DOI: 10.1016/j.mtphys.2026.102037

Lin Tian , Haibo Xu , Zengyao Li , Xinpeng Zhao

Windows are among the weakest components of building envelopes, accounting for up to 50% of total energy loss from buildings. Conventional solar control coatings, such as silver-based low-emissivity (low-E) films, demonstrate solar spectral selectivity, effectively reducing solar heat gain in summer by blocking near-infrared radiation. However, their static optical properties also block desirable solar heat gain in winter, thereby restricting year‐round energy efficiency. Herein, we propose an IHO/MgF₂/VO₂/MgF₂/IHO/MgF₂ multilayer coating that provides dynamic solar modulation, high luminous transparency, and low mid-infrared (MIR) emissivity simultaneously. This structure integrates thermochromic VO₂ for dynamic near-infrared (NIR) switching with hydrogen-doped indium oxide (IHO) as a transparent low-E layer, while anti-reflective MgF₂ layers maximize visible comfort. To ensure high solar heat modulation ability while balancing luminous transmission and radiative heat loss (i.e., MIR emissivity), a genetic-algorithms-coupled transfer-matrix method was employed to optimize material selection and layer thickness. The optimized design achieves a solar heat gain modulation ability of 7% and a U-value of ∼1.78 W/(m²·K) while maintaining a luminous transmittance of ∼60% in double-glazed windows, representing a 250% improvement in modulation capability compared to single-layer VO₂ coatings (2%) and a 33% enhancement in visible transmission compared to bare VO₂ films (45%). Whole-building energy analysis indicates that applying this coating to medium office buildings reduces energy consumption by 21.8% compared to conventional double-glazed windows and 8.4% compared to low-E windows. This work provides a promising solution for next-generation smart windows that effectively balance solar heat gain with thermal insulation, offering significant potential for reducing global building energy consumption while maintaining occupant visual comfort.

窗户是建筑围护结构中最薄弱的部分之一，占建筑总能量损失的50%。传统的太阳控制涂层，如银基低发射率（low-E）薄膜，展示了太阳光谱选择性，通过阻挡近红外辐射有效地减少了夏季的太阳热增益。然而，它们的静态光学特性也会在冬季阻碍理想的太阳能热增益，从而限制全年的能源效率。在此，我们提出了一种IHO/MgF2/VO2/MgF2/IHO/MgF2多层涂层，同时提供动态太阳调制，高发光透明度和低中红外（MIR）发射率。该结构集成了用于动态近红外（NIR）切换的热致变色VO2和氢掺杂氧化铟（IHO）作为透明的低e层，而抗反射MgF2层则最大限度地提高了可见舒适性。为了保证高的太阳热调制能力，同时平衡发光传输和辐射热损失（即MIR发射率），采用遗传算法耦合传递矩阵方法对材料选择和层厚进行优化。优化后的设计实现了7%的太阳热增益调制能力和~ 1.78 W/（m2·K）的u值，同时在双层玻璃窗中保持了~ 60%的透光率，与单层VO2涂层（2%）相比，调制能力提高了250%，与裸VO2膜（45%）相比，可见光透射率提高了33%。整体建筑能源分析表明，与传统双层玻璃窗相比，将这种涂层应用于中型办公大楼可减少21.8%的能源消耗，与低能耗窗户相比可减少8.4%的能源消耗。这项工作为下一代智能窗户提供了一个有前途的解决方案，它有效地平衡了太阳能的热量增益和隔热，在保持居住者视觉舒适的同时，为减少全球建筑能耗提供了巨大的潜力。

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引用次数: 0

Heterogeneous Fe/Ti3C2Tx MXene derived magnetic-dielectric synergy for efficient microwave attenuation at ultrathin thickness 非均相Fe/Ti3C2Tx MXene衍生磁介电协同在超薄厚度下的高效微波衰减

IF 9.7 2区材料科学 Q1 MATERIALS SCIENCE, MULTIDISCIPLINARY

Materials Today Physics

Pub Date : 2026-02-01 DOI: 10.1016/j.mtphys.2026.102034

Kexun Li , Fangyu Shi , Yanxia Wu , Min Zhao , Ying Liu

Modulating the electromagnetic properties of Ti₃C₂T_x MXene to produce an ideal multifunctional and efficient microwave absorbent is a challenging research hotspot. Although the atomic layer deposited transition magnetic metal nanostructures are a feasible strategy, the effects of the components and microstructure of the introduced magnetic nanostructure on the electromagnetic wave absorption performances of the MXene are still far from clear. Here, the Fe element has been selected as the modifier, and a heterostructure Fe/Ti₃C₂T_x MXene hybrid is constructed by the atomic layer deposition of Fe nanoparticles on the Ti₃C₂T_x nanosheets. The influences of the deposition cycles on the chemical composition, microstructure, electromagnetic response characteristics, and microwave absorption properties are investigated. The results show that the decoration of Fe nanoparticles enables a tunable electromagnetic performance. The Fe/Ti₃C₂T_x MXene hybrid achieves an optimal attenuation with the minimum reflection loss of -82.94 dB at a small thickness of 1.16 mm, corresponding with an effective absorption bandwidth of 3.76 GHz. The strong microwave absorption is attributed to the dielectric-magnetic synergy in the MXene and Fe nanoparticles, which provides excellent impedance matching, interfacial and dipolar polarization loss, and magnetic resonance loss. Specifically, the hybrid endows a low Fe content of 2.66 wt%. This is important for the design of a lightweight absorber with high attenuation efficiency.

调制Ti3C2Tx MXene的电磁特性以制备理想的多功能高效微波吸收剂是一个具有挑战性的研究热点。虽然原子层沉积过渡磁性金属纳米结构是一种可行的策略，但引入的磁性纳米结构的组成和微观结构对MXene电磁波吸收性能的影响尚不清楚。本文选择Fe元素作为改性剂，通过在Ti3C2Tx纳米片上原子层沉积Fe纳米粒子，构建了Fe/Ti3C2Tx MXene杂化结构。研究了沉积周期对化学成分、微观结构、电磁响应特性和微波吸收性能的影响。结果表明，铁纳米粒子的修饰使其电磁性能可调。Fe/Ti3C2Tx MXene复合材料在1.16 mm薄层处的反射损耗最小，为-82.94 dB，有效吸收带宽为3.76 GHz。强微波吸收是由于MXene和Fe纳米颗粒的介电-磁协同作用，提供了良好的阻抗匹配，界面和偶极极化损耗以及磁共振损耗。其中，杂化产物铁含量较低，为2.66 wt%。这对于设计具有高衰减效率的轻量化吸收体是非常重要的。

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引用次数: 0

From structure to sensing: Metal Organic Framework for ammonia gas detection 从结构到传感：用于氨气检测的金属有机框架

IF 9.7 2区材料科学 Q1 MATERIALS SCIENCE, MULTIDISCIPLINARY

Materials Today Physics

Pub Date : 2026-02-01 DOI: 10.1016/j.mtphys.2026.102029

Mohammad Yaasar Moosa , P. Uma Sathyakam

Ammonia (NH₃) serves as a significant environmental pollutant, a clinically important biomarker, and a critical target in industrial process monitoring. These varied roles drive the need for high-performance gas sensors that can operate effectively at room temperature. Metal–Organic Frameworks (MOFs) have emerged as promising materials for gas sensing due to their high surface area, tunable pore architecture, and tailorable chemical properties. This review critically analyses recent advances in MOF-based ammonia sensors from a structure-to-sensing performance perspective, highlighting how rational structural design directly governs sensing behavior. Key strategies—including pore size optimization, the incorporation of open metal sites, linker functionalization with acidic or polar groups, defect engineering, and metal encapsulation are evaluated for their ability to enhance NH₃ adsorption through Lewis acid–base interactions and hydrogen bonding. These structural features directly contribute to the exceptional sensing characterized by sub-ppm to ppb-level detection limits, large response amplitudes, rapid response/recovery times at room temperature, and improved selectivity. Post-synthetic modifications that improve stability and sensing reliability under high humidity conditions are also examined. By correlating MOF structural characteristics with experimentally demonstrated sensing benchmarks, this review provides a clear framework for the rational design and scalable integration of MOF-based ammonia sensors, supporting their transition from laboratory studies to practical sensing devices.

氨（NH3）是一种重要的环境污染物，是临床上重要的生物标志物，也是工业过程监测的重要靶点。这些不同的作用推动了对可在室温下有效工作的高性能气体传感器的需求。金属有机框架（mof）由于其高表面积、可调节的孔隙结构和可定制的化学性质，已成为气敏材料中很有前途的材料。这篇综述从结构到传感性能的角度批判性地分析了基于mof的氨传感器的最新进展，强调了合理的结构设计如何直接控制传感行为。关键策略——包括孔径优化、开放金属位点的结合、连接体与酸性或极性基团的功能化、缺陷工程和金属封装——通过路易斯酸碱相互作用和氢键来增强NH3吸附的能力。这些结构特征直接促成了特殊的传感特征，其检测限为亚ppm至ppb级，响应幅度大，室温下响应/恢复时间快，选择性提高。还研究了在高湿条件下提高稳定性和传感可靠性的合成后修饰。通过将MOF结构特征与实验验证的传感基准相关联，本综述为基于MOF的氨传感器的合理设计和可扩展集成提供了清晰的框架，支持其从实验室研究过渡到实际传感设备。

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引用次数: 0

Ultrahigh responsivity β-Ga2O3 solar-blind ultraviolet photodetectors through in-situ growth pressure-tuned defect engineering 基于原位生长压力调谐缺陷工程的超高响应率β-Ga2O3日盲紫外探测器

IF 9.7 2区材料科学 Q1 MATERIALS SCIENCE, MULTIDISCIPLINARY

Materials Today Physics

Pub Date : 2026-02-01 DOI: 10.1016/j.mtphys.2026.102030

Jiayi Liu , Dongyang Han , Shujun Zhu , Xiaoli Zhang , Shulin Hu , Kaisen Liu , Wenrui Zhang , Jichun Ye

β-Ga₂O₃ is a promising material for solar-blind ultraviolet (UV) photodetectors, yet its performance is often limited by native point defects. Here, we demonstrate ultrahigh performance β-Ga₂O₃ photodetectors through in-situ defect engineering via growth-pressure modulation during metal-organic chemical vapor deposition. Systematic variation of deposition pressure from 40 to 100 mbar reveals a nonmonotonic formation of gallium-oxygen divacancy (V_Ga–V_O) complexes governed by competing effects of precursor transport, surface nucleation, and adatom migration kinetics. X-ray photoelectron spectroscopy and photoluminescence analyses confirm that an intermediate pressure of 80 mbar maximizes V_Ga–V_O defect incorporation by balancing adatom mobility and precursor kinetics. The V_Ga–V_O complexes act as deep-level hole traps, prolonging carrier lifetimes and generating strong photoconductive gain. The β-Ga₂O₃ photodetector grown at 80 mbar exhibits an ultrahigh responsivity of 1.40 × 10⁴ A/W, a photo-to-dark current ratio of 1.88 × 10⁷, a detectivity of 1.12 × 10¹⁴ Jones, and rapid rise/decay times of 33.9/10.5 ms. This study establishes growth pressure-tuned defect engineering as an effective strategy for tailoring the optoelectronic properties of β-Ga₂O₃, providing a viable pathway toward high-performance solar-blind UV photodetectors.

β-Ga2O3是一种很有前途的太阳盲紫外（UV）光电探测器材料，但其性能往往受到原生点缺陷的限制。在这里，我们通过原位缺陷工程，通过金属有机化学气相沉积过程中的生长压力调制，展示了超高性能的β-Ga2O3光电探测器。沉积压力从40到100毫巴的系统变化表明，镓-氧空位（VGa-VO）复合物的非单调形成受前驱体传输、表面成核和附原子迁移动力学的竞争影响。x射线光电子能谱和光致发光分析证实，通过平衡附原子迁移率和前体动力学，80毫巴的中间压力使VGa-VO缺陷掺入最大化。VGa-VO配合物作为深能级空穴陷阱，延长载流子寿命并产生强光导增益。在80mbar下生长的β-Ga2O3光电探测器具有1.40 × 104 A/W的超高响应率、1.88 × 107的光暗比、1.12 × 1014 Jones的检出率和33.9/10.5 ms的快速上升/衰减时间。本研究建立了生长压力调谐缺陷工程作为定制β-Ga2O3光电特性的有效策略，为高性能太阳盲UV光电探测器提供了可行的途径。

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引用次数: 0