2D

2D
  • 文章类型: Journal Article
    异质结构工程对于提高气体传感性能至关重要。然而,通过合理的异质结构设计实现室温NO2传感的快速响应仍然是一个挑战。在这项研究中,通过水热法合成了Bi2Se3/SnSe22D/2D异质结构,用于室温下NO2的快速检测。通过将Bi2Se3纳米片与SnSe2纳米片相结合,Bi2Se3/SnSe2传感器证明,在室温下对10ppmNO2的响应时间短(15s),对NO2的最低检测限,达到25ppb。此外,传感器对NO2的响应明显大于对其他干扰气体的响应,包括10ppmNO2、H2S、NH3,CH4,CO,和SO2,证明了其出色的选择性。并讨论了相关性能增强的机理。
    Heterostructure engineering is crucial for enhancing gas sensing performance. However, achieving rapid response for room-temperature NO2 sensing through rational heterostructure design remains a challenge. In this study, a Bi2Se3/SnSe2 2D/2D heterostructure was synthesized by hydrothermal method for the rapid detection of NO2 at room temperature. By combining Bi2Se3 nanosheets with SnSe2 nanosheets, the Bi2Se3/SnSe2 sensor demonstrated and the lowest detection limit for NO2 a short response time (15 s) to 10 ppm NO2 at room temperature, reaches 25 ppb. Furthermore the sensor demonstrates significantly larger response to NO2 than to other interfering gases, including 10 ppm NO2, H2S, NH3, CH4, CO, and SO2,demonstrating its outstanding selectivity. And we discuss the mechanism of related performance enhancement.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

       PDF(Pubmed)

  • 文章类型: Journal Article
    偏振在扩展光网络容量方面起着至关重要的作用。各向异性二维(2D)材料提供了在各种光子和光电应用中利用光学偏振敏感响应的机会。然而,光纤在线器件中光学各向异性的探索,对超快脉冲产生和调制至关重要,仍然有限。在这项研究中,我们提出了一种基于单晶tcareene纳米片的纤维集成装置。受益于手性链晶格和独特的光学二向色性,可以实现具有多种优异性能的多功能光学器件。通过将在线设备插入1.5μm光纤激光器腔中,我们产生了线性偏振和双波长锁模脉冲,其偏振度为98%,并且具有出色的长期稳定性。通过扭曲配置的两个tcarrene纳米片,我们实现了具有快速响应的全光交换操作。该多功能器件还用作宽带光电探测器。值得注意的是,在没有任何外部电压的情况下,可以实现1550nm的双极偏振编码通信。该器件在周围环境中的多功能性和稳定性为将偏振作为光纤网络中的附加物理维度提供了一个有前途的原型。涵盖光产生的各种应用,调制,和检测。
    Polarization plays a paramount role in scaling the optical network capacity. Anisotropic two-dimensional (2D) materials offer opportunities to exploit optical polarization-sensitive responses in various photonic and optoelectronic applications. However, the exploration of optical anisotropy in fiber in-line devices, critical for ultrafast pulse generation and modulation, remains limited. In this study, we present a fiber-integrated device based on a single-crystalline tellurene nanosheet. Benefiting from the chiral-chain crystal lattice and distinct optical dichroism of tellurene, multifunctional optical devices possessing diverse excellent properties can be achieved. By inserting the in-line device into a 1.5 μm fiber laser cavity, we generated both linearly polarized and dual-wavelength mode-locking pulses with a degree of polarization of 98% and exceptional long-term stability. Through a twisted configuration of two tellurene nanosheets, we realized an all-optical switching operation with a fast response. The multifunctional device also serves as a broadband photodetector. Notably, bipolar polarization encoding communication at 1550 nm can be achieved without any external voltage. The device\'s multifunctionality and stability in ambient environments established a promising prototype for integrating polarization as an additional physical dimension in fiber optical networks, encompassing diverse applications in light generation, modulation, and detection.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

    求助全文

  • 文章类型: Journal Article
    近年来,MXene已成为广泛探索用于各种应用的最吸引人的二维层状(2Dl)材料之一。在这项研究中,开发了Ti3C2MXene/rGo-Cu2O纳米复合材料(TGCNCs),以有效地从水生环境中消除Safranin-O(SO)和酸性品红(AF)作为阳离子染料。多步骤参与吸附剂系统的制备,包括Ti3C2的制备,Humer法合成GO,其次是rGO生产,然后添加CuSO4以获得称为“TGCNCs”的最终纳米复合材料(NCs)。TGCNCs的结构可以以几种方式变化,包括FTIR,SEM,TGA,泽塔,EDX,XRD,而BET,确认TGCNCs的有效制备。开发了一种新型的吸附剂系统来去除SO和AF,两种阳离子染料。通过批量吸附试验优化了各种吸附条件,包括溶液的pH值(4-12),剂量的影响(0.003-0.03克),接触时间的影响(5-30分钟),以及起始染料浓度(25-250mg/L)的影响。因此,TGCNCs表现出对Freundlich等温线模式的极好拟合,产生909.09和769.23毫克的最大AF和SO吸附能力。g-1.对吸附动力学的研究表明,伪二阶(PSO)模型将与实验数据(=0.998和=0.990)很好地拟合。从热力学参数可以明显看出,吸附是自发且有利的吸热过程。在SO和AF吸附到NC上的过程中,假设这些分子通过堆叠相互作用在分子内相互作用,H-键相互作用,静电相互作用,和截留在聚合物Poros结构纳米复合材料内。对于所研究的两种有机染料,最有效的是持续五个循环的再生研究。
    In recent years, MXene has become one of the most intriguing two-dimensional layered (2Dl) materials extensively explored for various applications. In this study, a Ti3C2 MXene/rGo-Cu2O Nanocomposite (TGCNCs) was developed to eliminate Safranin-O effectively (SO) and Acid Fuchsin (AF) as cationic dyes from the aquatic environment. Multistep was involved in the preparation of the adsorbent system, including the Preparation of Ti3C2, after that, GO synthesis by the Humer method, followed by rGO production, then added CuSO4 to obtain a final Nanocomposite (NCs) called \"TGCNCs\". The structure of TGCNCs can be varied in several ways, including FTIR, SEM, TGA, Zeta, EDX, XRD, and BET, to affirm the efficacious preparation of TGCNCs. A novel adsorbent system was developed to remove SO and AF, both cationic dyes. Various adsorption conditions have been optimized through batch adsorption tests, including the pH of the solution (4-12), the effect of dosage (0.003-0.03 g), the impact of the contact time (5-30 min), and the effect of beginning dye concentration (25-250 mg/L). Accordingly, the TGCNCs exhibited excellent fitting for Freundlich isotherm mode, resulting in maximum AF and SO adsorption capacities of 909.09 and 769.23 mg g-1. This research on adsorption kinetics suggests that a pseudo-second-order (PSO) model would fit well with the experimental data (RSO2 = 0.998 and RAF2 = 0.990). It is evident from the thermodynamic parameters that adsorption is an endothermic process that is spontaneous and favorable. During the adsorption of SO and AF onto NCs, it is hypothesized that these molecules interact intramolecularly through stacking interactions, H-bond interactions, electrostatic interactions, and entrapment within the polymeric Poros structure nanocomposite. Regeneration studies lasting up to five cycles were the most effective for both organic dyes under study.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

    求助全文

  • 文章类型: Journal Article
    本研究旨在探讨3D腹腔镜在经腹腹膜前腹股沟疝(TAPP)手术老年患者中的安全性和有效性。根据手术期间使用的腹腔镜设备将患者分为两组。术前临床数据,术中,收集和术后资料进行统计分析。从2020年1月到2023年8月,这项研究共评估了127例原发性单侧腹股沟疝患者。3DTAPP组中61和2DTAPP组中66。基线数据差异无统计学意义,包括平均年龄,性别分布,BMI指数,疝类型,疝缺损的大小和位置,合并症,两组抗凝药物使用情况比较(P>0.05)。在操作指标方面,3D组平均手术时间较短(51.61±7.16minvs.78.59±13.51分钟,P<0.001),平均网格放置时间(6.07±1.40minvs.9.77±1.21分钟,P<0.001),和平均腹膜缝合时间(7.34±1.85minvs.9.73±1.32min,P<0.001)与2D组相比。然而,平均失血量没有统计学上的显著差异,术后疼痛评分,术后住院时间,两组住院总费用比较(P>0.05)。两组术后并发症发生率差异无统计学意义(P>0.05)。两组患者手术期间均未出现头晕、恶心等不良反应。三维腹腔镜在TAPP手术中提供高清晰度,三维手术图像,降低操作难度,有效缩短操作时间。
    This study aims to explore the safety and efficacy of 3D laparoscopy in elderly patients undergoing transabdominal preperitoneal (TAPP) surgery for inguinal hernia. Patients were divided into two groups based on the laparoscopic equipment used during surgery. Clinical data preoperatively, intraoperatively, and postoperatively were collected and subjected to statistical analysis. From January 2020 to August 2023, a total of 127 patients with primary unilateral inguinal hernia were evaluated in this study, 61 in the 3D TAPP group and 66 in the 2D TAPP group. There were no statistically significant differences in baseline data, including average age, gender distribution, BMI index, hernia type, hernia defect size and location, comorbidities, and usage of anticoagulant drugs between the two groups (P > 0.05). In terms of operative indicators, the 3D group showed shorter mean operation time (51.61 ± 7.16 min vs. 78.59 ± 13.51 min, P < 0.001), mean mesh placement time (6.07 ± 1.40 min vs. 9.77 ± 1.21 min, P < 0.001), and mean peritoneal suture time (7.34 ± 1.85 min vs. 9.73 ± 1.32 min, P < 0.001) compared to the 2D group. However, there were no statistically significant differences in mean blood loss, postoperative pain scores, postoperative hospital stay, and total hospital costs between the two groups (P > 0.05). The incidence of postoperative complications did not differ significantly between the two groups (P > 0.05). No adverse reactions such as dizziness or nausea were reported by surgeons during the procedures in either group. Three-dimensional laparoscopy in TAPP surgery provides high-definition, three-dimensional surgical images, reducing the difficulty of operations and effectively shortening the operation time.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

    求助全文

  • 文章类型: Journal Article
    通过第一性原理计算,从大块半HeuslerZrNiSn设计了一种用于热电应用的新型2D半HeuslerZrNiSn纳米片。已通过基于密度泛函理论-平面波基础集的量子浓缩代码对块状半Heusler和2DZrNiSn纳米片进行了研究。电子能带结构和态密度计算用于研究约束效应。在由于限制而从散装移动到2D时,从面心立方到三角观察到结构的变化。当移动到2D纳米片时,块状ZrNiSn的半导体性质不受干扰,然而,由于电子在一个方向上的运动受限,带隙从0.46扩展到1.3eV。与块状ZrNiSn相比,发现2D纳米片具有较高的塞贝克系数,低热导率和高ZT,使2DZrNiSn纳米片适用于热电应用。具有原子级薄性质和平坦表面的二维结构具有形成范德华异质结的潜力,为纳米级器件制造铺平了道路。 .
    A novel two-dimensional (2D) half-HeuslerZrNiSn nanosheetfor thermoelectric applications was designed from bulk half-Heusler ZrNiSn through first-principles calculation. Investigation of bulk half-Heusler and 2D nanosheet ZrNiSn was performed with the Quantum Espresso code based on a density functional theory plane wave basis set. Electronic band structure and density of states calculations were used to study the confinement effects. On moving from bulk to 2D a change of structure is observed from face-centered cubic to trigonal due to confinement effects. The semiconducting nature of bulk ZrNiSn is undisturbed while moving to a 2D nanosheet; however, the band gap is widened from 0.46 to 1.3 eV due to the restricted motion of electrons in one direction. Compared with bulk ZrNiSn, 2D nanosheets were found to have a higher Seebeck coefficient a lower thermal conductivity and higher figure of merit, which makes 2D ZrNiSn nanosheets suitable for thermoelectric applications. Atomically thin 2D structures with a flat surface have the potential to form van der Waals heterojunctions, paving the way for device fabrication at the nanoscale level.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

    求助全文

  • 文章类型: Journal Article
    背景:本研究旨在评估2D腹腔镜与3D腹腔镜治疗结直肠癌的有效性和安全性。
    方法:通过PubMed进行了文献检索,WebofScience,和Embase从成立到2024年1月。包括调查结直肠手术不同结局的研究。结果以比值比(OR)或平均差(MD)表示,具有95%置信区间(CI)。本次审查的协议已在PROSPERO(CRD42024504902)上注册。
    结果:本文检索到10篇文献。3D组与术中出血量的显着改善相关(MD=-8.04,95%CI=-14.18至-1.89,P=0.01,I2=55%),手术时间(MD=-17.33,95%CI=-29.15~-5.51,P=0.004,I2=90%),和术后住院时间(MD=-0.23,95%CI=-0.43至-0.04,P=0.02,I2=48%)与2D组患者相比,特别是对于三个结果以上的直肠癌患者(MD=-10.36,95%CI=-15.00至-5.73,P<0.001,I2=0%),(MD=-18.85,95%CI=-34.88至-2.82,P=0.02,I2=57%),和(MD=-0.93,95%CI=-1.53至-0.34,P=0.002,I2=0%),分别。经肛门排气时间(MD=-0.14,95%CI=-0.49~0.21,P=0.44,I2=79%)和淋巴结清扫数(MD=0.36,95%CI=-0.49~1.21,P=0.41,I2=45%)差异无统计学意义,但是3D组的直肠癌患者术后肛门排气较早(MD=-0.46,95%CI=-0.66至-0.27,P<0.001,I2=0%),并且结肠癌患者的淋巴结清扫数量更多(MD=1.54,95%CI=0.05至3.03,P=0.04,I2=69%)。两组术后总并发症(OR=0.94,95%CI=0.67~1.31,P=0.71,I2=0%)和吻合口漏(OR=0.93,95%CI=0.48~1.80,P=0.83,I2=0%)比较,差异无统计学意义。无论直肠癌和结肠手术患者。
    结论:这项荟萃分析表明,3D腹腔镜可以减少失血量,加速术后通过排气,并缩短直肠癌根治术的手术时间和术后住院时间,对于结肠癌根治术无明显优势。此外,3D腹腔镜检查可增加结肠癌根治术的淋巴结数量,但在直肠癌手术中可能未观察到。
    BACKGROUND: This study aimed to evaluate the effectiveness and safety of 2D laparoscopy vs 3D laparoscopy for the treatment of colorectal cancer.
    METHODS: A literature search was conducted through PubMed, Web of Science, and Embase from their inception to January 2024. Studies investigating different outcomes of colorectal surgery were included. Results are presented as odds ratios (ORs) or mean differences (MDs) with 95% confidence intervals (CIs). The protocol for this review has been registered on PROSPERO (CRD42024504902).
    RESULTS: A total of 10 publications were retrieved in this article. The 3D group is associated with a significant improvement in intraoperative blood loss (MD = -8.04, 95% CI = -14.18 to -1.89, P = 0.01, I2 = 55%), operative time (MD = -17.33, 95% CI = -29.15 to -5.51, P = 0.004, I2 = 90%), and postoperative hospital stay (MD = -0.23, 95% CI = -0.43 to -0.04, P = 0.02, I2 = 48%) compared to that of patients treated in the 2D group, particularly for rectal cancer patients above three results (MD = -10.36, 95% CI = -15.00 to -5.73, P < 0.001, I2 = 0%), (MD = -18.85, 95% CI = -34.88 to -2.82, P = 0.02, I2 = 57%), and (MD = -0.93, 95% CI = -1.53 to -0.34, P = 0.002, I2 = 0%), respectively. There was no significant statistical difference in the time of pass flatus (MD = -0.14, 95% CI = -0.49 to  0.21, P = 0.44, I2 = 79%) and the number of dissected lymph nodes (MD = 0.36, 95% CI = -0.49 to 1.21, P = 0.41, I2 = 45%), but the 3D group had an earlier postoperative pass flatus for rectal cancer patients (MD = -0.46, 95% CI = -0.66 to -0.27, P<0.001, I2 = 0%) and the more number of dissected lymph nodes for colon cancer patients (MD = 1.54, 95% CI = 0.05 to 3.03, P = 0.04, I2 = 69%) than the 2D group. There was no significant difference in postoperative overall complication (OR = 0.94, 95% CI = 0.67 to 1.31, P = 0.71, I2 = 0%) and anastomotic leakage (OR = 0.93, 95% CI = 0.48 to 1.80, P = 0.83, I2 = 0%) in the two groups, regardless of rectal cancer and colon surgery patients.
    CONCLUSIONS: This meta-analysis demonstrates that 3D laparoscopy could reduce the amount of blood loss, accelerate postoperative pass flatus, and shorten the operation time and postoperative hospital stay over 2D for radical rectal cancer surgery, without obvious advantage for radical colon cancer surgery. Moreover, 3D laparoscopy increases the number of dissected lymph nodes for radical colon cancer surgery but may not be observed in rectal cancer surgery.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

    求助全文

  • 文章类型: Journal Article
    石墨烯(GDY)是一种新型纳米碳材料,具有优异的化学性能,物理和电子特性。它在光学领域的广泛作用引起了研究者和实业家的广泛关注,电子,生物医疗和能源。sp-sp2碳原子的独特排列,直链炔属连接,均匀的孔隙和高度共轭的结构为进一步探索GDY材料提供了许多潜力。然而,由于材料处于起步阶段,对它的属性没有太多的了解,生长机制和未来应用。因此,在这次审查中,读者将通过对GDY属性的简短讨论来引导,不同的合成程序,特别关注表面功能化和GDY的应用列表。该综述还批判性地分析了每种合成路线的优缺点,并强调了材料的未来范围。
    Graphdiyne (GDY) is a new variant of nano-carbon material with excellent chemical, physical and electronic properties. It has attracted wide attention from researchers and industrialists for its extensive role in the fields of optics, electronics, bio-medics and energy. The unique arrangement of sp-sp2 carbon atoms, linear acetylenic linkages, uniform pores and highly conjugated structure offer numerous potentials for further exploration of GDY materials. However, since the material is at its infancy, not much understanding is available regarding its properties, growth mechanism and future applications. Therefore, in this review, readers are guided through a brief discussion on GDY\'s properties, different synthesis procedures with a special focus on surface functionalization and a list of applications for GDY. The review also critically analyses the advantages and disadvantages of each synthesis route and emphasizes the future scope of the material.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

    求助全文

  • 文章类型: Journal Article
    随着MBenes的出现,2D材料领域取得了显着进步,源自MAX相位系列的新材料,一类新的材料,起源于MAX阶段家庭。在这里,本文探讨了MBenes的独特特征和形态变异,全面概述了它们的结构演变。首先,讨论探讨了与几种合成技术相关的2DMBenes的进化时期,修改,并表征MBenes以定制其结构并增强其功能。然后焦点转移到MBenes的缺陷化学上,电子,催化,和光热特性在设计多功能太阳能驱动混合系统中起着至关重要的作用。第二,2DMBenes在太阳能驱动的混合动力系统中的最新进展和潜力,例如光电催化,用于淡水和热电发电机的混合太阳能蒸发器,和光疗,强调它们在解决能源和环境问题方面的关键意义,正在探索。该研究进一步探索了调节MBenes改善的光催化和光热特性的基本原理,强调他们对有效利用太阳能和修复环境的承诺。这项研究还彻底评估了MBenes的可扩展性,稳定性,和太阳能驱动系统的成本效益。当前的见解和未来的方向使研究人员能够利用MBenes进行可持续和多样化的应用。这篇关于MBenes的评论对于早期研究人员来说是有价值的,他们对合成和利用2D材料用于太阳能水能燃料和光疗系统感兴趣。
    The field of 2D materials has advanced significantly with the emergence of MBenes, a new material derived from the MAX phases family, a novel class of materials that originates from the MAX phases family. Herein, this article explores the unique characteristics and morphological variations of MBenes, offering a comprehensive overview of their structural evolution. First, the discussion explores the evolutionary period of 2D MBenes associated with the several techniques for synthesizing, modifying, and characterizing MBenes to tailor their structure and enhance their functionality. The focus then shifts to the defect chemistry of MBenes, electronic, catalytic, and photothermal properties which play a crucial role in designing multifunctional solar-driven hybrid systems. Second, the recent advancements and potentials of 2D MBenes in solar-driven hybrid systems e.g. photo-electro catalysis, hybrid solar evaporators for freshwater and thermoelectric generators, and phototherapy, emphasizing their crucial significance in tackling energy and environmental issues, are explored. The study further explores the fundamental principles that regulate the improved photocatalytic and photothermal characteristics of MBenes, highlighting their promise for effective utilization of solar energy and remediation of the environment. The study also thoroughly assesses MBenes\' scalability, stability, and cost effectiveness in solar-driven systems. Current insights and future directions allow researchers to utilize MBenes for sustainable and varied applications. This review regarding MBenes will be valuable to early researchers intrigued with synthesizing and utilizing 2D materials for solar-powered water-energy-fuel and phototherapy systems.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

    求助全文

  • 文章类型: Journal Article
    二维范德华(2DvdW)材料中自旋轨道转矩(SOT)技术的最新进展不仅将自旋电子器件推向了原子极限,而且还揭示了非常规的转矩和新颖的自旋切换机制。在许多2DvdW材料中观察到的SOT的巨大多样性需要筛选策略来确定用于扭矩装置性能的最佳材料。然而,这一战略尚未确立。为了解决这个关键问题,采用密度泛函理论和非平衡格林函数的组合来计算各种2DvdW双层异质结构中的SOT。这导致发现了三个高SOT系统:WTe2/CrSe2、MoTe2/VS2和NbSe2/CrSe2。此外,提出了一个允许快速有效估计SOT的品质因数,为未来的SOT应用提供最佳材料和设备的高通量筛选。
    Recent advancements in spin-orbit torque (SOT) technology in two-dimensional van der Waals (2D vdW) materials have not only pushed spintronic devices to their atomic limits but have also unveiled unconventional torques and novel spin-switching mechanisms. The vast diversity of SOT observed in numerous 2D vdW materials necessitates a screening strategy to identify optimal materials for torque device performance. However, such a strategy has yet to be established. To address this critical issue, a combination of density functional theory and non-equilibrium Green\'s function is employed to calculate the SOT in various 2D vdW bilayer heterostructures. This leads to the discovery of three high SOT systems: WTe2/CrSe2, MoTe2/VS2, and NbSe2/CrSe2. Furthermore, a figure of merit that allows for rapid and efficient estimation of SOT is proposed, enabling high-throughput screening of optimal materials and devices for SOT applications in the future.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

    求助全文

  • 文章类型: Journal Article
    二维(2D)杂化有机-无机卤化物钙钛矿已成为一类新型的2D半导体,具有将出色的光电特性与诸如铁电性之类的对称特性相结合的潜力。尽管已经报道了许多铅基铁电2D卤化物钙钛矿,目前还没有关于锡基二维钙钛矿铁电性的结论性报告。这里,我们报告了一系列新的2DDion-Jacobson(DJ)Sn钙钛矿的结构和性能:(4AMP)SnI4,(4AMP)(MA)Sn2I7和(4AMP)(FA)Sn2I7(4AMP=4-(氨基甲基)哌啶,MA=甲基铵,和FA=甲脒)。结构表征表明(4AMP)SnI4具有平面内自发极化的极性,而(4AMP)(MA)Sn2I7和(4AMP)(FA)Sn2I7是中心对称的。此外,(4AMP)SnI4显示二次谐波产生(SHG),极化-电场滞后测量证实它是铁电的,在室温下自发极化为10.0µCcm-2。(4AMP)SnI4转变为367K以上的中心对称结构。作为对锡基2D混合钙钛矿的自发铁电极化的首次直接实验观察,这项工作为铁电性和其他物理性质研究开辟了环保的2D卤化锡钙钛矿。本文受版权保护。保留所有权利。
    2D hybrid organic-inorganic halide perovskites emerge as a new class of 2D semiconductors with the potential to combine excellent optoelectronic properties with symmetry-enabled properties such as ferroelectricity. Although many lead-based ferroelectric 2D halide perovskites are reported, there is yet to be a conclusive report of ferroelectricity in tin-based 2D perovskites. Here, the structures and properties of a new series of 2D Dion-Jacobson (DJ) Sn perovskites: (4AMP)SnI4, (4AMP)(MA)Sn2I7, and (4AMP)(FA)Sn2I7 (4AMP = 4-(aminomethyl)piperidinium, MA = methylammonium, and FA = formamidinium), are reported. Structural characterization reveals that (4AMP)SnI4 is polar with in-plane spontaneous polarization whereas (4AMP)(MA)Sn2I7 and (4AMP)(FA)Sn2I7 are centrosymmetric. Further, (4AMP)SnI4 displays second harmonic generation (SHG) and polarization-electric field hysteresis measurements confirm it is ferroelectric with a spontaneous polarization of 10.0 µC cm-2 at room temperature. (4AMP)SnI4 transitions into a centrosymmetric structure above 367 K. As the first direct experimental observation of the spontaneous ferroelectric polarization of a Sn-based 2D hybrid perovskite, this work opens up environmentally friendly 2D tin halide perovskites for ferroelectricity and other physical property studies.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

    求助全文

公众号