Haibin Li, Zhiheng Sun, Yue Liu, Yi Xing, Jing Gao, Aihong Shi, Yadong Yu, Jin Long, Dong‐Po Song, Chao Jin, Marc D. McKee, Jun‐An Ma, Wenge Jiang
Functional chiral suprastructures are common in biology, including in biomineralization, and they are frequently found in many hardened structures of both marine and terrestrial invertebrates, and even in pathologic human otoconia of the inner ear. However, the biological processes by which they form remain unclear. Here, we show that chiral hierarchical suprastructures of calcium sulfate dihydrate (gypsum) can be induced by the chiral Aspartic acid (Asp). Left‐handed (clockwise) morphology of gypsum is induced by the d‐enantiomer of Asp, while right‐handed (counterclockwise) morphology is induced by the l‐enantiomer. A layer‐by‐layer, oriented inclination mineral growth model controlled by continuous self‐assembly of chiral Asp enantiomers on an amorphous calcium sulfate mineral surface of gypsum platelet layers is postulated to produce these chiral architectures. This hybrid amorphous‐crystallized chiral and hierarchical suprastructure of gypsum displays outstanding mechanical properties, including high‐performance strength and toughness. Furthermore, the induction of chiral gypsum suprastructures can be more generally extended from specific acidic amino acids to other (nonamino acid) molecules. These findings contribute to our understanding of the molecular mechanisms by which biomineral‐associated enantiomers exert structural control over chiral architectures commonly seen in biominerals and in biomimetically synthesized functional materials.
功能性手性超结构在生物学中很常见,包括在生物矿化过程中,它们经常出现在海洋和陆地无脊椎动物的许多硬化结构中,甚至出现在病态的人类内耳耳膜中。然而,它们形成的生物过程仍不清楚。在这里,我们展示了手性天冬氨酸(Asp)可以诱导二水硫酸钙(石膏)的手性分层超结构。石膏的左旋(顺时针)形态由 Asp 的 d 对映体诱导,而右旋(逆时针)形态则由 l 对映体诱导。在石膏板层的无定形硫酸钙矿物表面,手性 Asp 对映体通过连续自组装控制逐层定向倾斜矿物生长模型,从而产生了这些手性结构。这种无定形-结晶手性和分层混合结构的石膏具有出色的机械性能,包括高性能的强度和韧性。此外,手性石膏超微结构的诱导可以从特定的酸性氨基酸扩展到其他(非氨基酸)分子。这些发现有助于我们理解生物矿物相关对映体对生物矿物和生物模拟合成功能材料中常见的手性结构进行结构控制的分子机制。
{"title":"Chiral gypsum with high‐performance mechanical properties induced by self‐assembly of chiral amino acid on an amorphous mineral","authors":"Haibin Li, Zhiheng Sun, Yue Liu, Yi Xing, Jing Gao, Aihong Shi, Yadong Yu, Jin Long, Dong‐Po Song, Chao Jin, Marc D. McKee, Jun‐An Ma, Wenge Jiang","doi":"10.1002/smm2.1302","DOIUrl":"https://doi.org/10.1002/smm2.1302","url":null,"abstract":"Functional chiral suprastructures are common in biology, including in biomineralization, and they are frequently found in many hardened structures of both marine and terrestrial invertebrates, and even in pathologic human otoconia of the inner ear. However, the biological processes by which they form remain unclear. Here, we show that chiral hierarchical suprastructures of calcium sulfate dihydrate (gypsum) can be induced by the chiral Aspartic acid (Asp). Left‐handed (clockwise) morphology of gypsum is induced by the d‐enantiomer of Asp, while right‐handed (counterclockwise) morphology is induced by the l‐enantiomer. A layer‐by‐layer, oriented inclination mineral growth model controlled by continuous self‐assembly of chiral Asp enantiomers on an amorphous calcium sulfate mineral surface of gypsum platelet layers is postulated to produce these chiral architectures. This hybrid amorphous‐crystallized chiral and hierarchical suprastructure of gypsum displays outstanding mechanical properties, including high‐performance strength and toughness. Furthermore, the induction of chiral gypsum suprastructures can be more generally extended from specific acidic amino acids to other (nonamino acid) molecules. These findings contribute to our understanding of the molecular mechanisms by which biomineral‐associated enantiomers exert structural control over chiral architectures commonly seen in biominerals and in biomimetically synthesized functional materials.","PeriodicalId":21794,"journal":{"name":"SmartMat","volume":"5 9","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141684983","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
D. Simatos, M. Nikolka, J. Charmet, L. Spalek, Z. Toprakcioglu, Ian E. Jacobs, I. Dimov, G. Schweicher, Mi Jung Lee, C. Fernández-Posada, Duncan J. Howe, T. Hakala, L. W. Roode, Vincenzo Pecunia, Thomas P. Sharp, Weimin Zhang, Maryam Alsufyani, Iain McCulloch, T. Knowles, Henning Sirringhaus
A key component of organic bioelectronics is electrolyte‐gated organic field‐effect transistors (EG‐OFETs), which have recently been used as sensors to demonstrate label‐free, single‐molecule detection. However, these devices exhibit limited stability when operated in direct contact with aqueous electrolytes. Ultrahigh stability is demonstrated to be achievable through the utilization of a systematic multifactorial approach in this study. EG‐OFETs with operational stability and lifetime several orders of magnitude higher than the state of the art have been fabricated by carefully controlling a set of intricate stability‐limiting factors, including contamination and corrosion. The indacenodithiophene‐co‐benzothiadiazole (IDTBT) EG‐OFETs exhibit operational stability that exceeds 900 min in a variety of widely used electrolytes, with an overall lifetime exceeding 2 months in ultrapure water and 1 month in various electrolytes. The devices were not affected by electrical stress‐induced trap states and can remain stable even in voltage ranges where electrochemical doping occurs. To validate the applicability of our stabilized device for biosensing applications, the reliable detection of the protein lysozyme in ultrapure water and in a physiological sodium phosphate buffer solution for 1500 min was demonstrated. The results show that polymer‐based EG‐OFETs are a viable architecture not only for short‐term but also for long‐term biosensing applications.
{"title":"Electrolyte‐gated organic field‐effect transistors with high operational stability and lifetime in practical electrolytes","authors":"D. Simatos, M. Nikolka, J. Charmet, L. Spalek, Z. Toprakcioglu, Ian E. Jacobs, I. Dimov, G. Schweicher, Mi Jung Lee, C. Fernández-Posada, Duncan J. Howe, T. Hakala, L. W. Roode, Vincenzo Pecunia, Thomas P. Sharp, Weimin Zhang, Maryam Alsufyani, Iain McCulloch, T. Knowles, Henning Sirringhaus","doi":"10.1002/smm2.1291","DOIUrl":"https://doi.org/10.1002/smm2.1291","url":null,"abstract":"A key component of organic bioelectronics is electrolyte‐gated organic field‐effect transistors (EG‐OFETs), which have recently been used as sensors to demonstrate label‐free, single‐molecule detection. However, these devices exhibit limited stability when operated in direct contact with aqueous electrolytes. Ultrahigh stability is demonstrated to be achievable through the utilization of a systematic multifactorial approach in this study. EG‐OFETs with operational stability and lifetime several orders of magnitude higher than the state of the art have been fabricated by carefully controlling a set of intricate stability‐limiting factors, including contamination and corrosion. The indacenodithiophene‐co‐benzothiadiazole (IDTBT) EG‐OFETs exhibit operational stability that exceeds 900 min in a variety of widely used electrolytes, with an overall lifetime exceeding 2 months in ultrapure water and 1 month in various electrolytes. The devices were not affected by electrical stress‐induced trap states and can remain stable even in voltage ranges where electrochemical doping occurs. To validate the applicability of our stabilized device for biosensing applications, the reliable detection of the protein lysozyme in ultrapure water and in a physiological sodium phosphate buffer solution for 1500 min was demonstrated. The results show that polymer‐based EG‐OFETs are a viable architecture not only for short‐term but also for long‐term biosensing applications.","PeriodicalId":21794,"journal":{"name":"SmartMat","volume":"38 30","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-06-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141339951","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Flexible, wearable electronics are the future of electronics. Although organic photovoltaic devices have the advantages of high efficiency, low cost, and flexibility, they face the problem of failure due to the effects of water vapor in the environment. Therefore, the development of encapsulation films with outstanding mechanical and encapsulation properties is the key to realizing wearable devices. This review provides an overview of the development of thin‐film encapsulation (TFE), the application of TFE in the field of optoelectronics, recent advances in the field of flexible encapsulation with TFE using atomic layer deposition technology, and an outlook on future trends in the field of flexible encapsulation with TFE using atomic layer deposition technology.
{"title":"Efforts of implementing ultra‐flexible thin‐film encapsulation for optoelectronic devices based on atomic layer deposition technology","authors":"Guanran Wang, Yu Duan","doi":"10.1002/smm2.1286","DOIUrl":"https://doi.org/10.1002/smm2.1286","url":null,"abstract":"Flexible, wearable electronics are the future of electronics. Although organic photovoltaic devices have the advantages of high efficiency, low cost, and flexibility, they face the problem of failure due to the effects of water vapor in the environment. Therefore, the development of encapsulation films with outstanding mechanical and encapsulation properties is the key to realizing wearable devices. This review provides an overview of the development of thin‐film encapsulation (TFE), the application of TFE in the field of optoelectronics, recent advances in the field of flexible encapsulation with TFE using atomic layer deposition technology, and an outlook on future trends in the field of flexible encapsulation with TFE using atomic layer deposition technology.","PeriodicalId":21794,"journal":{"name":"SmartMat","volume":"17 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-04-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140696601","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Lei Shi, Ke Shi, Zhi-Cheng Zhang, Yuan Li, Fu‐Dong Wang, Shu‐Han Si, Zhi‐Bo Liu, Tong‐Bu Lu, Xu‐Dong Chen, Jin Zhang
Bioinspired neuromorphic machine vision system (NMVS) that integrates retinomorphic sensing and neuromorphic computing into one monolithic system is regarded as the most promising architecture for visual perception. However, the large intensity range of natural lights and complex illumination conditions in actual scenarios always require the NMVS to dynamically adjust its sensitivity according to the environmental conditions, just like the visual adaptation function of the human retina. Although some opto‐sensors with scotopic or photopic adaption have been developed, NMVSs, especially fully flexible NMVSs, with both scotopic and photopic adaptation functions are rarely reported. Here we propose an ion‐modulation strategy to dynamically adjust the photosensitivity and time‐varying activation/inhibition characteristics depending on the illumination conditions, and develop a flexible ion‐modulated phototransistor array based on MoS2/graphdiyne heterostructure, which can execute both retinomorphic sensing and neuromorphic computing. By controlling the intercalated Li+ ions in graphdiyne, both scotopic and photopic adaptation functions are demonstrated successfully. A fully flexible NMVS consisting of front‐end retinomorphic vision sensors and a back‐end convolutional neural network is constructed based on the as‐fabricated 28 × 28 device array, demonstrating quite high recognition accuracies for both dim and bright images and robust flexibility. This effort for fully flexible and monolithic NMVS paves the way for its applications in wearable scenarios.
{"title":"Flexible retinomorphic vision sensors with scotopic and photopic adaptation for a fully flexible neuromorphic machine vision system","authors":"Lei Shi, Ke Shi, Zhi-Cheng Zhang, Yuan Li, Fu‐Dong Wang, Shu‐Han Si, Zhi‐Bo Liu, Tong‐Bu Lu, Xu‐Dong Chen, Jin Zhang","doi":"10.1002/smm2.1285","DOIUrl":"https://doi.org/10.1002/smm2.1285","url":null,"abstract":"Bioinspired neuromorphic machine vision system (NMVS) that integrates retinomorphic sensing and neuromorphic computing into one monolithic system is regarded as the most promising architecture for visual perception. However, the large intensity range of natural lights and complex illumination conditions in actual scenarios always require the NMVS to dynamically adjust its sensitivity according to the environmental conditions, just like the visual adaptation function of the human retina. Although some opto‐sensors with scotopic or photopic adaption have been developed, NMVSs, especially fully flexible NMVSs, with both scotopic and photopic adaptation functions are rarely reported. Here we propose an ion‐modulation strategy to dynamically adjust the photosensitivity and time‐varying activation/inhibition characteristics depending on the illumination conditions, and develop a flexible ion‐modulated phototransistor array based on MoS2/graphdiyne heterostructure, which can execute both retinomorphic sensing and neuromorphic computing. By controlling the intercalated Li+ ions in graphdiyne, both scotopic and photopic adaptation functions are demonstrated successfully. A fully flexible NMVS consisting of front‐end retinomorphic vision sensors and a back‐end convolutional neural network is constructed based on the as‐fabricated 28 × 28 device array, demonstrating quite high recognition accuracies for both dim and bright images and robust flexibility. This effort for fully flexible and monolithic NMVS paves the way for its applications in wearable scenarios.","PeriodicalId":21794,"journal":{"name":"SmartMat","volume":"117 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-04-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140708775","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Peri‐implant infection is one of the major causes for implant failure. The transmucosal/transcutaneous surface of implant abutment is directly connected to the external environment and constantly exposed to a large number of bacteria. Establishing a robust anti‐biofilm barrier at the abutment surface to minimize the risk of peri‐implant infection is highly desirable in the field of dental implantology but remains challenging. Herein, a new class of therapeutic abutments featuring excellent anti‐biofilm performance is developed, which is achieved by admirably integrating the outstanding self‐cleaning property of polyethylene glycol and the long‐lasting renewable antibacterial property of N‐halamine. Through a comprehensive series of in vitro and in vivo experiments closely mimicking clinical conditions, therapeutic abutments have been successfully demonstrated to possess the ability of inhibiting biofilm accumulation to prevent peri‐implant infection, as well as to achieve persistent and accurate administration to reverse early‐stage peri‐implant infection. Furthermore, the therapeutic abutment could be repeatedly used, representing the characteristic of sustainable medical devices. These findings indicate a new paradigm for the prevention and treatment of peri‐implant infection.
{"title":"Coral‐inspired anti‐biofilm therapeutic abutments as a new paradigm for prevention and treatment of peri‐implant infection","authors":"Weiran Li, Zhike Huang, Xin Li, Mengqi Zhang, Qianqian Li, Shulu Luo, Yan Li, Dingcai Wu, Shuyi Wu","doi":"10.1002/smm2.1284","DOIUrl":"https://doi.org/10.1002/smm2.1284","url":null,"abstract":"Peri‐implant infection is one of the major causes for implant failure. The transmucosal/transcutaneous surface of implant abutment is directly connected to the external environment and constantly exposed to a large number of bacteria. Establishing a robust anti‐biofilm barrier at the abutment surface to minimize the risk of peri‐implant infection is highly desirable in the field of dental implantology but remains challenging. Herein, a new class of therapeutic abutments featuring excellent anti‐biofilm performance is developed, which is achieved by admirably integrating the outstanding self‐cleaning property of polyethylene glycol and the long‐lasting renewable antibacterial property of N‐halamine. Through a comprehensive series of in vitro and in vivo experiments closely mimicking clinical conditions, therapeutic abutments have been successfully demonstrated to possess the ability of inhibiting biofilm accumulation to prevent peri‐implant infection, as well as to achieve persistent and accurate administration to reverse early‐stage peri‐implant infection. Furthermore, the therapeutic abutment could be repeatedly used, representing the characteristic of sustainable medical devices. These findings indicate a new paradigm for the prevention and treatment of peri‐implant infection.","PeriodicalId":21794,"journal":{"name":"SmartMat","volume":"17 4","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-04-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140709937","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Jingyu Mao, Tengyu Jin, Xiangyu Hou, Siew Lang Teo, Ming Lin, Jingsheng Chen, Wei Chen
In dealing with the increasing power dissipation of electronic systems with increasing integration density, a field‐effect transistor (FET) with steep switching slope that overcomes the thermionic limit is vital to achieve low‐power operations. Here, we report two types of threshold switching (TS) FETs based on 2D Van der Waals heterostructures by virtue of the abrupt resistive switching of the hexagonal boron nitride (hBN) TS device. The common hBN dielectric layer functions as the switching medium for the TS device and the gate dielectric for the 2D FET enabling seamless integration of the hBN TS device and baseline 2D FET. TS FET in source configuration by connecting the TS device to the source terminal of the 2D FET offers an ultralow average subthreshold swing (SS) of 1.6 mV/dec over six decades of drain current at room temperature and suppressed leakage current. TS FET in gate configuration by connecting the TS device to the gate terminal of the 2D FET also exhibits steep switching slope with ultralow SS of 10.6 mV/dec. The proposed compact device structures integrating 2D FET and TS device provide a potential approach of monolithic integration toward next‐generation low‐power electronics.
{"title":"Steep slope threshold switching field‐effect transistors based on 2D heterostructure","authors":"Jingyu Mao, Tengyu Jin, Xiangyu Hou, Siew Lang Teo, Ming Lin, Jingsheng Chen, Wei Chen","doi":"10.1002/smm2.1283","DOIUrl":"https://doi.org/10.1002/smm2.1283","url":null,"abstract":"In dealing with the increasing power dissipation of electronic systems with increasing integration density, a field‐effect transistor (FET) with steep switching slope that overcomes the thermionic limit is vital to achieve low‐power operations. Here, we report two types of threshold switching (TS) FETs based on 2D Van der Waals heterostructures by virtue of the abrupt resistive switching of the hexagonal boron nitride (hBN) TS device. The common hBN dielectric layer functions as the switching medium for the TS device and the gate dielectric for the 2D FET enabling seamless integration of the hBN TS device and baseline 2D FET. TS FET in source configuration by connecting the TS device to the source terminal of the 2D FET offers an ultralow average subthreshold swing (SS) of 1.6 mV/dec over six decades of drain current at room temperature and suppressed leakage current. TS FET in gate configuration by connecting the TS device to the gate terminal of the 2D FET also exhibits steep switching slope with ultralow SS of 10.6 mV/dec. The proposed compact device structures integrating 2D FET and TS device provide a potential approach of monolithic integration toward next‐generation low‐power electronics.","PeriodicalId":21794,"journal":{"name":"SmartMat","volume":"9 12","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-03-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140369364","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Yujeong Jeong, Talshyn Begildayeva, J. Theerthagiri, Ahreum Min, C. J. Moon, Jangyun Kim, S. S. Naik, Myong Yong Choi
Herein, an in situ approach of pulsed laser irradiation in liquids (PLIL) was exploited to create surface‐modified electrodes for eco‐friendly H2 fuel production via electrolysis. The surface of the nickel foam (NF) substrate was nondestructively modified in 1.0 mol/L KOH using PLIL, resulting in a highly reactive Ni(OH)2/NF. Moreover, single‐metal Ir, Ru, and Pd nanoclusters were introduced onto Ni(OH)2/NF via appropriate metal precursors. This simultaneous surface oxidation of the NF to Ni(OH)2 and decoration with reduced metallic nanoparticles during PLIL are advantageous for promoting hydrogen evolution reaction (HER) and oxygen evolution reaction (OER), and overall water splitting (OWS). The Ir‐Ni(OH)2/NF electrode demonstrates superior performance, achieving the lowest overpotentials at 10 mA/cm2 (η) with 74 mV (HER) and 268 mV (OER). The OWS using Ir‐Ni(OH)2/NF||Ir‐Ni(OH)2/NF cell demonstrated a low voltage of 1.592 V, reaching 10 mA/cm2 with notable stability of 72 h. Ir‐Ni(OH)2/NF performance is assigned to the improved defects and boosted intrinsic properties resulting from the synergy between metallic‐nanoparticles and the oxidized NF surface, which are positively influenced by PLIL.
{"title":"Laser‐driven liquid assembly: Metal‐nanocluster‐decorated Ni(OH)2/nickel foam for efficient water electrolysis","authors":"Yujeong Jeong, Talshyn Begildayeva, J. Theerthagiri, Ahreum Min, C. J. Moon, Jangyun Kim, S. S. Naik, Myong Yong Choi","doi":"10.1002/smm2.1281","DOIUrl":"https://doi.org/10.1002/smm2.1281","url":null,"abstract":"Herein, an in situ approach of pulsed laser irradiation in liquids (PLIL) was exploited to create surface‐modified electrodes for eco‐friendly H2 fuel production via electrolysis. The surface of the nickel foam (NF) substrate was nondestructively modified in 1.0 mol/L KOH using PLIL, resulting in a highly reactive Ni(OH)2/NF. Moreover, single‐metal Ir, Ru, and Pd nanoclusters were introduced onto Ni(OH)2/NF via appropriate metal precursors. This simultaneous surface oxidation of the NF to Ni(OH)2 and decoration with reduced metallic nanoparticles during PLIL are advantageous for promoting hydrogen evolution reaction (HER) and oxygen evolution reaction (OER), and overall water splitting (OWS). The Ir‐Ni(OH)2/NF electrode demonstrates superior performance, achieving the lowest overpotentials at 10 mA/cm2 (η) with 74 mV (HER) and 268 mV (OER). The OWS using Ir‐Ni(OH)2/NF||Ir‐Ni(OH)2/NF cell demonstrated a low voltage of 1.592 V, reaching 10 mA/cm2 with notable stability of 72 h. Ir‐Ni(OH)2/NF performance is assigned to the improved defects and boosted intrinsic properties resulting from the synergy between metallic‐nanoparticles and the oxidized NF surface, which are positively influenced by PLIL.","PeriodicalId":21794,"journal":{"name":"SmartMat","volume":" 22","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-03-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140220321","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Xueyan Zhao, Yan Yan, Min Tan, Surong Zhang, Xiaona Xu, Zhibin Zhao, Maoning Wang, Xubin Zhang, Adila Adijiang, Zongliang Li, E. Scheer, Dong Xiang
Thanks to their excellent bond strength, phenyl‐based molecules with thiol anchoring groups are extensively employed to form stable single‐molecule junctions. However, two critical questions are still not answered which seriously hinder high‐yield establishing reliable molecular functional devices: (1) Whether molecular dimer junctions will be formed, and if this is the case, whether the dimerization is caused by intermolecular disulfide bonds or π–π stacking of phenyl rings; (2) Upon a mechanical‐compression force, is it possible that both anchoring groups of the molecule bond to the same electrode instead of bridging two opposite electrodes, which would drastically reduce the yield of the molecular junctions. Here, combining UV‐Vis/Raman spectroscopy of bulk molecules and conductance/flicker‐noise measurements of single molecules, we give compelling evidence that molecular dimers naturally form under ambient conditions, primarily via disulfide bonds rather than by π–π stacking. We further proposed a technique, named electrode‐compression‐hold‐on (ECHO), and reveal that the two thiol groups of phenyl‐backboned molecules will bond to the same electrode upon a compression force with a prolongated ECHO time. In contrast, the compression‐time‐dependent phenomenon is not observed for alkyl‐backboned molecules. The underlying mechanism for these unprecedented observations is elucidated, shedding light on the yield of molecular junctions.
{"title":"Molecular dimer junctions forming: Role of disulfide bonds and electrode‐compression‐time","authors":"Xueyan Zhao, Yan Yan, Min Tan, Surong Zhang, Xiaona Xu, Zhibin Zhao, Maoning Wang, Xubin Zhang, Adila Adijiang, Zongliang Li, E. Scheer, Dong Xiang","doi":"10.1002/smm2.1280","DOIUrl":"https://doi.org/10.1002/smm2.1280","url":null,"abstract":"Thanks to their excellent bond strength, phenyl‐based molecules with thiol anchoring groups are extensively employed to form stable single‐molecule junctions. However, two critical questions are still not answered which seriously hinder high‐yield establishing reliable molecular functional devices: (1) Whether molecular dimer junctions will be formed, and if this is the case, whether the dimerization is caused by intermolecular disulfide bonds or π–π stacking of phenyl rings; (2) Upon a mechanical‐compression force, is it possible that both anchoring groups of the molecule bond to the same electrode instead of bridging two opposite electrodes, which would drastically reduce the yield of the molecular junctions. Here, combining UV‐Vis/Raman spectroscopy of bulk molecules and conductance/flicker‐noise measurements of single molecules, we give compelling evidence that molecular dimers naturally form under ambient conditions, primarily via disulfide bonds rather than by π–π stacking. We further proposed a technique, named electrode‐compression‐hold‐on (ECHO), and reveal that the two thiol groups of phenyl‐backboned molecules will bond to the same electrode upon a compression force with a prolongated ECHO time. In contrast, the compression‐time‐dependent phenomenon is not observed for alkyl‐backboned molecules. The underlying mechanism for these unprecedented observations is elucidated, shedding light on the yield of molecular junctions.","PeriodicalId":21794,"journal":{"name":"SmartMat","volume":"12 10","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-03-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140239271","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}