Pub Date : 2024-03-05DOI: 10.1088/2632-959x/ad2b82
Abin Philip, A Ruban Kumar
Owing to its exceptional structural, electrical, and optical features, Molybdenum disulphide (MoS2), a two-dimensional (2D) layered material with tuneable bandgap, finds its application in electrochemical supercapacitors for superior energy and power density. Because of their low toxicity and long-term energy storage, the development of MoS2-based supercapacitors is inevitable. The study of solvent effects on the electrochemical performance of a few layered MoS2 using FTO substrates is done for the first time to the best of our knowledge. Exfoliating bulk MoS2 powder in different solvents with variable surface tensions such as Ethanol, Ethylene Glycol (EG), Dimethylformamide (DMF), and Dimethyl Sulfoxide (DMSO) results in the formation of few-layered MoS2 structures. The sample’s structural, optical, and electrochemical behaviours are investigated using x-ray diffraction (XRD), atomic force microscopy (AFM), UV spectroscopy, Fourier transform infrared (FTIR), cyclic-voltammetry (CV), galvanostatic charge–discharge (GCD), and electrochemical impedance spectroscopy (EIS). XRD confirms the formation of a 2D MoS2 film with (002) planes and the optical investigation revealed the variation of layer-dependent bandgap with solvents. We observe both faradaic and non-faradaic charge storage mechanisms in the samples and demonstrate a superior pseudocapacitive behaviour for MoS2 in DMF with a maximum specific capacitance of 34.25 F g−1 at a current density of 1 A/g.
{"title":"Solvent effects on the electrochemical performance of few layered MoS2 electrodes fabricated using FTO substrates","authors":"Abin Philip, A Ruban Kumar","doi":"10.1088/2632-959x/ad2b82","DOIUrl":"https://doi.org/10.1088/2632-959x/ad2b82","url":null,"abstract":"Owing to its exceptional structural, electrical, and optical features, Molybdenum disulphide (MoS<sub>2</sub>), a two-dimensional (2D) layered material with tuneable bandgap, finds its application in electrochemical supercapacitors for superior energy and power density. Because of their low toxicity and long-term energy storage, the development of MoS<sub>2</sub>-based supercapacitors is inevitable. The study of solvent effects on the electrochemical performance of a few layered MoS<sub>2</sub> using FTO substrates is done for the first time to the best of our knowledge. Exfoliating bulk MoS<sub>2</sub> powder in different solvents with variable surface tensions such as Ethanol, Ethylene Glycol (EG), Dimethylformamide (DMF), and Dimethyl Sulfoxide (DMSO) results in the formation of few-layered MoS<sub>2</sub> structures. The sample’s structural, optical, and electrochemical behaviours are investigated using x-ray diffraction (XRD), atomic force microscopy (AFM), UV spectroscopy, Fourier transform infrared (FTIR), cyclic-voltammetry (CV), galvanostatic charge–discharge (GCD), and electrochemical impedance spectroscopy (EIS). XRD confirms the formation of a 2D MoS<sub>2</sub> film with (002) planes and the optical investigation revealed the variation of layer-dependent bandgap with solvents. We observe both faradaic and non-faradaic charge storage mechanisms in the samples and demonstrate a superior pseudocapacitive behaviour for MoS<sub>2</sub> in DMF with a maximum specific capacitance of 34.25 F g<sup>−1</sup> at a current density of 1 A/g.","PeriodicalId":501827,"journal":{"name":"Nano Express","volume":"93 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140315602","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}
Pub Date : 2024-03-05DOI: 10.1088/2632-959x/ad2b80
Peuli Nath, Aniruddha Ray
All inorganic perovskite nanocrystals (CsPbX3 NCs) have excellent optical properties with high quantum yield, size tunable absorption and emission spectra which makes them popular for a wide variety of applications. All the commonly used synthesis techniques, such as hot injection and ligand assisted reprecipitation method (LARP), use ‘good’ solvent such as dimethyl formamide, dimethyl sulfoxide or octadecene to dissolve the precursor salts. The CsPbX3 NCs formation is triggered either by rapid injection of the dissolved precursor salt in hot mixture (hot injection) or by adding a ‘good’ solvent into a ‘poor’ solvent (LARP) that induces crystallization. Here, we present an alternative synthesis of CsPbX3 perovskite nanocrystals in an antisolvent system, instead of a ‘good’ solvent. Crystallization in the antisolvent is induced by adding a trace amount of water, leading to the formation of highly bright CsPbX3 nanocrystals. This method resulted in a maximum photoluminescent quantum yield of ∼91%. Furthermore, these CsPbBr3 NCs can be modified to create core–shell structures with polymers such as silica, in the same pot. Encapsulating the NCs within a protective silica shell resulted in vastly superior water stability compared to the bare NCs. The silica coated CsPbBr3 NCs showed strong fluorescence in water were used to label breast cancer cells, thereby demonstrating its potential as an optical contrast agent for advanced bioimaging applications. Overall, this synthesis approach requires minimal steps and time, and can be carried out in an ambient atmosphere, thereby increasing its versatility and practicality, which is particularly attractive in low-resource settings.
{"title":"One-step synthesis of highly fluorescent perovskite nanocrystals in antisolvent for bioimaging","authors":"Peuli Nath, Aniruddha Ray","doi":"10.1088/2632-959x/ad2b80","DOIUrl":"https://doi.org/10.1088/2632-959x/ad2b80","url":null,"abstract":"All inorganic perovskite nanocrystals (CsPbX<sub>3</sub> NCs) have excellent optical properties with high quantum yield, size tunable absorption and emission spectra which makes them popular for a wide variety of applications. All the commonly used synthesis techniques, such as hot injection and ligand assisted reprecipitation method (LARP), use ‘good’ solvent such as dimethyl formamide, dimethyl sulfoxide or octadecene to dissolve the precursor salts. The CsPbX<sub>3</sub> NCs formation is triggered either by rapid injection of the dissolved precursor salt in hot mixture (hot injection) or by adding a ‘good’ solvent into a ‘poor’ solvent (LARP) that induces crystallization. Here, we present an alternative synthesis of CsPbX<sub>3</sub> perovskite nanocrystals in an antisolvent system, instead of a ‘good’ solvent. Crystallization in the antisolvent is induced by adding a trace amount of water, leading to the formation of highly bright CsPbX<sub>3</sub> nanocrystals. This method resulted in a maximum photoluminescent quantum yield of ∼91%. Furthermore, these CsPbBr<sub>3</sub> NCs can be modified to create core–shell structures with polymers such as silica, in the same pot. Encapsulating the NCs within a protective silica shell resulted in vastly superior water stability compared to the bare NCs. The silica coated CsPbBr<sub>3</sub> NCs showed strong fluorescence in water were used to label breast cancer cells, thereby demonstrating its potential as an optical contrast agent for advanced bioimaging applications. Overall, this synthesis approach requires minimal steps and time, and can be carried out in an ambient atmosphere, thereby increasing its versatility and practicality, which is particularly attractive in low-resource settings.","PeriodicalId":501827,"journal":{"name":"Nano Express","volume":"21 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140315491","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}
Pub Date : 2024-03-01DOI: 10.1088/2632-959x/ad2b7e
Aditi Manna, N. Ray
Colloidal quantum dots (QDs) have emerged as transformative materials with diverse properties, holding tremendous promise for reshaping the landscape of photovoltaics and thermoelectrics. Emphasizing the pivotal role of surface ligands, ranging from extended hydrocarbon chains to intricate metal chalcogenide complexes, halides, and hybrid ligands, we underscore their influence on the electronic behavior of the assembly. The ability to tailor interdot coupling can have profound effects on charge transport, making colloidal QDs a focal point for research aimed at enhancing the efficiency and performance of energy conversion devices. This perspective provides insights into the multifaceted realm of QD solids, starting from fundamentals of charge transport through the coupled assemblies. We delve into recent breakthroughs, spotlighting champion devices across various architectures and elucidating the sequential advancements that have significantly elevated efficiency levels.
{"title":"Recent progress in photovoltaic and thermoelectric applications of coupled colloidal quantum dot solids: insights into charge transport fundamentals","authors":"Aditi Manna, N. Ray","doi":"10.1088/2632-959x/ad2b7e","DOIUrl":"https://doi.org/10.1088/2632-959x/ad2b7e","url":null,"abstract":"\u0000 Colloidal quantum dots (QDs) have emerged as transformative materials with diverse properties, holding tremendous promise for reshaping the landscape of photovoltaics and thermoelectrics. Emphasizing the pivotal role of surface ligands, ranging from extended hydrocarbon chains to intricate metal chalcogenide complexes, halides, and hybrid ligands, we underscore their influence on the electronic behavior of the assembly. The ability to tailor interdot coupling can have profound effects on charge transport, making colloidal QDs a focal point for research aimed at enhancing the efficiency and performance of energy conversion devices. This perspective provides insights into the multifaceted realm of QD solids, starting from fundamentals of charge transport through the coupled assemblies. We delve into recent breakthroughs, spotlighting champion devices across various architectures and elucidating the sequential advancements that have significantly elevated efficiency levels.","PeriodicalId":501827,"journal":{"name":"Nano Express","volume":"107 12","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140406859","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}
Pub Date : 2024-02-29DOI: 10.1088/2632-959x/ad2997
Vandana Sharma, J K Sharma, Vishal Kansay, Aarzoo Dutta, Mayank Raj, Manoj Singh, Anu Kapoor, Chhavi Pahwa, Anupam Sharma, Suresh Kumar, A K Sharma, M K Bera
Application of drug conjugated iron oxide hematite (α-Fe2O3) nanoparticles are of tremendous interest in biomedicine nowadays. Meanwhile, green production of iron oxide nanoparticles is gaining favour due to its sustainability, ease of usage, and biocompatibility. Therefore, this work reports on the use of hexahydrate ferric chloride and nerium oleander flower extract to synthesize nanoscaled hematite (α-Fe2O3) iron oxide particles conjugated with various drugs for antibacterial agents. Diverse morphological, physicochemical, structural, optical, and magnetic characteristics have been characterized using FESEM, EDX, XRD, UV–vis, FTIR, Raman and vibrating sample magnetometer. The synthesis of the polyshaped iron oxide nanoparticles, with average sizes ranging from 47.2 ± 20 nm, was accomplished. Furthermore, temperature-dependent variations in magnetic behavior were observed during calcination. The XRD and Raman spectra revealed hematite (α-Fe2O3) type formation of iron oxide nanoparticles. Only calcinated IO-NPs at high temperatures (700 °C) demonstrated low coercivity and residual magnetism, which revealed weak ferromagnetic ordering; other calcinated samples, including nascent ones, showed incredibly weak ferromagnetic ordering. Besides, the effectiveness of drug-encapsulated iron oxide nanoparticles against bacteria in vitro was examined. It was interesting to observe that gentamycin-coated IO-NPs tended to be more susceptible to S. aureus than E. coli bacteria, but streptomycin-conjugated IO-NPs showed the reverse trend. However, as compared to the nascent sample and the high temperature (700 °C) calcinated sample, both antibiotic-loaded IO-NPs displayed better inhibitory abilities.
{"title":"Green synthesis, characterization and drug-loaded iron oxide nanoparticles derived from Nerium oleander flower extract as a nanocarrier for in vitro antibacterial efficacy","authors":"Vandana Sharma, J K Sharma, Vishal Kansay, Aarzoo Dutta, Mayank Raj, Manoj Singh, Anu Kapoor, Chhavi Pahwa, Anupam Sharma, Suresh Kumar, A K Sharma, M K Bera","doi":"10.1088/2632-959x/ad2997","DOIUrl":"https://doi.org/10.1088/2632-959x/ad2997","url":null,"abstract":"Application of drug conjugated iron oxide hematite (<italic toggle=\"yes\">α</italic>-Fe<sub>2</sub>O<sub>3</sub>) nanoparticles are of tremendous interest in biomedicine nowadays. Meanwhile, green production of iron oxide nanoparticles is gaining favour due to its sustainability, ease of usage, and biocompatibility. Therefore, this work reports on the use of hexahydrate ferric chloride and <italic toggle=\"yes\">nerium oleander</italic> flower extract to synthesize nanoscaled hematite (<italic toggle=\"yes\">α</italic>-Fe<sub>2</sub>O<sub>3</sub>) iron oxide particles conjugated with various drugs for antibacterial agents. Diverse morphological, physicochemical, structural, optical, and magnetic characteristics have been characterized using FESEM, EDX, XRD, UV–vis, FTIR, Raman and vibrating sample magnetometer. The synthesis of the polyshaped iron oxide nanoparticles, with average sizes ranging from 47.2 ± 20 nm, was accomplished. Furthermore, temperature-dependent variations in magnetic behavior were observed during calcination. The XRD and Raman spectra revealed hematite (<italic toggle=\"yes\">α</italic>-Fe<sub>2</sub>O<sub>3</sub>) type formation of iron oxide nanoparticles. Only calcinated IO-NPs at high temperatures (700 °C) demonstrated low coercivity and residual magnetism, which revealed weak ferromagnetic ordering; other calcinated samples, including nascent ones, showed incredibly weak ferromagnetic ordering. Besides, the effectiveness of drug-encapsulated iron oxide nanoparticles against bacteria <italic toggle=\"yes\">in vitro</italic> was examined. It was interesting to observe that gentamycin-coated IO-NPs tended to be more susceptible to <italic toggle=\"yes\">S. aureus</italic> than <italic toggle=\"yes\">E. coli</italic> bacteria, but streptomycin-conjugated IO-NPs showed the reverse trend. However, as compared to the nascent sample and the high temperature (700 °C) calcinated sample, both antibiotic-loaded IO-NPs displayed better inhibitory abilities.","PeriodicalId":501827,"journal":{"name":"Nano Express","volume":"65 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-02-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140315595","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}
Pub Date : 2024-02-12DOI: 10.1088/2632-959x/ad246c
Natchanok Talapphet, Chang Soon Huh
The oxidizing agent, hydrogen peroxide (H2O2), which is a part of reactive oxygen species (ROS) is well-known to contribute to oxidative stress-induced damage to biological molecules. An excess of free radicals can harm health and is associated with human diseases. Gold nanotechnology, a highly relevant nanomaterial, has been utilized as a new material in advanced sensor detection. In this study, colorimetric methods based on peroxidase enzymes were developed for measuring H2O2. The synthesized gold nanoparticles (AuNPs) showed a concentration of approximately 1.73 nM at a wavelength of 520 nm. The average diameter displayed a uniform size distribution, estimated at 18 nm, and an increase in the shell thickness of AuNPs-horseradish peroxidase (HRP) was observed in the TEM images. The AuNPs-HRP system demonstrated remarkable catalytic activity in the reaction of the chromogenic substrate tetramethylbenzidine (TMB) with H2O2, resulting in the production of an oxide product. The optimal conditions for the AuNPs-HRP system, as determined by central composite design (CCD), were a temperature of 25 °C and a pH of 7 within an 8 h period. A strong linear relationship was observed between different absorbance values and the H2O2 concentration, with a coefficient of determination of 0.9956. A portable platform was successfully used to determine H2O2 levels in beverages with recoveries ranging from 95.51% to 118.85%. These findings suggest that the AuNPs-HRP system could be applied to detect H2O2 in beverages.
{"title":"The optimization of gold nanoparticles–horseradish peroxidase as peroxidase mimic using central composite design for the detection of hydrogen peroxide","authors":"Natchanok Talapphet, Chang Soon Huh","doi":"10.1088/2632-959x/ad246c","DOIUrl":"https://doi.org/10.1088/2632-959x/ad246c","url":null,"abstract":"The oxidizing agent, hydrogen peroxide (H<sub>2</sub>O<sub>2</sub>), which is a part of reactive oxygen species (ROS) is well-known to contribute to oxidative stress-induced damage to biological molecules. An excess of free radicals can harm health and is associated with human diseases. Gold nanotechnology, a highly relevant nanomaterial, has been utilized as a new material in advanced sensor detection. In this study, colorimetric methods based on peroxidase enzymes were developed for measuring H<sub>2</sub>O<sub>2</sub>. The synthesized gold nanoparticles (AuNPs) showed a concentration of approximately 1.73 nM at a wavelength of 520 nm. The average diameter displayed a uniform size distribution, estimated at 18 nm, and an increase in the shell thickness of AuNPs-horseradish peroxidase (HRP) was observed in the TEM images. The AuNPs-HRP system demonstrated remarkable catalytic activity in the reaction of the chromogenic substrate tetramethylbenzidine (TMB) with H<sub>2</sub>O<sub>2</sub>, resulting in the production of an oxide product. The optimal conditions for the AuNPs-HRP system, as determined by central composite design (CCD), were a temperature of 25 °C and a pH of 7 within an 8 h period. A strong linear relationship was observed between different absorbance values and the H<sub>2</sub>O<sub>2</sub> concentration, with a coefficient of determination of 0.9956. A portable platform was successfully used to determine H<sub>2</sub>O<sub>2</sub> levels in beverages with recoveries ranging from 95.51% to 118.85%. These findings suggest that the AuNPs-HRP system could be applied to detect H<sub>2</sub>O<sub>2</sub> in beverages.","PeriodicalId":501827,"journal":{"name":"Nano Express","volume":"29 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-02-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139764494","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}
Pub Date : 2024-01-12DOI: 10.1088/2632-959x/ad1de5
Cuixiu Wu, Wanyuan Huang, Fengyi Du, Miaomiao Zhang, Hanliang Qian
Zeolitic imidazolate framework-8 nanoparticles (ZIF-8 NPs) are emerging metal-organic framework nanomaterials composed of 2-methylimidazole and zinc ions, which are widely used in biomedical fields due to their distinctive features such as high porosity, bioresponsive degradation, and superior biocompatibility. Especially, the advanced research of ZIF-8 NPs in smart drug delivery systems is providing unique insights into the rational design of versatile nanomedicines for the treatment and diagnosis of serious diseases. This article provides a comprehensive review and outlook on ZIF-8 NPs-based smart drug delivery systems (SDDSs) including the synthesis methods, drug loading strategies, surface modification, and stimuli-responsive release. In particular, we focus on the advantages of ZIF-8 NPs-based drug loading strategies between the metal coordination-based active loading and the physical packaging-based passive loading. Finally, the opportunities and challenges of ZIF-8 NPs as smart drug delivery carriers are discussed.
{"title":"Engineering Zeolitic Imidazolate Framework-8 Nanoparticles for Smart Drug Delivery Systems","authors":"Cuixiu Wu, Wanyuan Huang, Fengyi Du, Miaomiao Zhang, Hanliang Qian","doi":"10.1088/2632-959x/ad1de5","DOIUrl":"https://doi.org/10.1088/2632-959x/ad1de5","url":null,"abstract":"\u0000 Zeolitic imidazolate framework-8 nanoparticles (ZIF-8 NPs) are emerging metal-organic framework nanomaterials composed of 2-methylimidazole and zinc ions, which are widely used in biomedical fields due to their distinctive features such as high porosity, bioresponsive degradation, and superior biocompatibility. Especially, the advanced research of ZIF-8 NPs in smart drug delivery systems is providing unique insights into the rational design of versatile nanomedicines for the treatment and diagnosis of serious diseases. This article provides a comprehensive review and outlook on ZIF-8 NPs-based smart drug delivery systems (SDDSs) including the synthesis methods, drug loading strategies, surface modification, and stimuli-responsive release. In particular, we focus on the advantages of ZIF-8 NPs-based drug loading strategies between the metal coordination-based active loading and the physical packaging-based passive loading. Finally, the opportunities and challenges of ZIF-8 NPs as smart drug delivery carriers are discussed.","PeriodicalId":501827,"journal":{"name":"Nano Express","volume":"22 2","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139532435","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}
Pub Date : 2024-01-04DOI: 10.1088/2632-959x/ad100c
Shanmuga Priya S, Suseem S R
Carbon dots are small carbon-based particles with unique properties that make them useful in various applications. Some advantages include low toxicity, bio-compatibility, excellent photo luminescence, high stability, and ease of synthesis. These features make them promising for biomedical imaging, drug delivery, and optoelectronic devices. Carbon dots derived from plants have several advantages, including their low toxicity, biocompatibility, and renewable sources. They also have excellent water solubility and high stability and can be easily synthesized using simple and low-cost methods. These properties make them promising candidates for various biomedicine, sensing, and imaging applications. Plant-based carbon dots have shown great potential in metal sensing and bio-imaging applications. They can act as efficient sensors for detecting heavy metals due to their strong chelation and fluorescence properties. This article showcases plant-based carbon dots, emphasizing their low toxicity, biocompatibility, renewability, and potential in metal sensing and bio-imaging. It aims to illustrate their versatile applications and ongoing research for broader use. The current investigation explores their full potential and develops new synthesis and application methods.
{"title":"Plant-based carbon dots are a sustainable alternative to conventional nanomaterials for biomedical and sensing applications","authors":"Shanmuga Priya S, Suseem S R","doi":"10.1088/2632-959x/ad100c","DOIUrl":"https://doi.org/10.1088/2632-959x/ad100c","url":null,"abstract":"Carbon dots are small carbon-based particles with unique properties that make them useful in various applications. Some advantages include low toxicity, bio-compatibility, excellent photo luminescence, high stability, and ease of synthesis. These features make them promising for biomedical imaging, drug delivery, and optoelectronic devices. Carbon dots derived from plants have several advantages, including their low toxicity, biocompatibility, and renewable sources. They also have excellent water solubility and high stability and can be easily synthesized using simple and low-cost methods. These properties make them promising candidates for various biomedicine, sensing, and imaging applications. Plant-based carbon dots have shown great potential in metal sensing and bio-imaging applications. They can act as efficient sensors for detecting heavy metals due to their strong chelation and fluorescence properties. This article showcases plant-based carbon dots, emphasizing their low toxicity, biocompatibility, renewability, and potential in metal sensing and bio-imaging. It aims to illustrate their versatile applications and ongoing research for broader use. The current investigation explores their full potential and develops new synthesis and application methods.","PeriodicalId":501827,"journal":{"name":"Nano Express","volume":"6 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139092869","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}
The exponential growth of large data and the widespread adoption of the Internet of Things (IoT) have created significant challenges for traditional Von Neumann computers. These challenges include complex hardware, high energy consumption, and slow memory access time. Researchers are investigating novel materials and device architectures to address these issues by reducing energy consumption, improving performance, and enabling compact designs. A new study has successfully engineered a heterostructure that integrates Sb2Se3 and Sb2S3, resulting in improved electrical properties. This has generated significant interest in its potential applications in resistive switching. In this study, we have demonstrated the fabrication of a device based on Sb2S3/Sb2Se3 heterostructure that exhibits resistive switching behavior. The device has different resistance states that can be switched between high and low resistance levels when exposed to an external bias (−1 V to 0 V to 1 V). It also has good non-volatile memory characteristics, including low power consumption, high resistance ratio (∼102), and reliable endurance (∼103). The device enables faster data processing, reduces energy consumption, and streamlines hardware designs, contributing to computing advancements amidst modern challenges. This approach can revolutionize resistive switching devices, leading to more efficient computing solutions for big data processing and IoT technologies.
大数据的指数级增长和物联网（IoT）的广泛应用给传统的冯-诺依曼计算机带来了巨大挑战。这些挑战包括复杂的硬件、高能耗和缓慢的内存访问时间。研究人员正在研究新型材料和器件架构，以通过降低能耗、提高性能和实现紧凑设计来解决这些问题。一项新的研究成功地设计出了一种集成了 Sb2Se3 和 Sb2S3 的异质结构，从而改善了电气性能。这引起了人们对其在电阻开关中潜在应用的极大兴趣。在本研究中，我们展示了一种基于 Sb2S3/Sb2Se3 异质结构的器件，该器件具有电阻开关行为。该器件具有不同的电阻状态，当受到外部偏压（-1 V 至 0 V 至 1 V）时，可在高阻和低阻之间切换。它还具有良好的非易失性存储器特性，包括低功耗、高电阻比（∼102）和可靠的耐用性（∼103）。该器件可加快数据处理速度、降低能耗并简化硬件设计，从而在现代挑战中推动计算技术的进步。这种方法可以彻底改变电阻开关器件，为大数据处理和物联网技术带来更高效的计算解决方案。
{"title":"Fabrication of Sb2S3/Sb2Se3 heterostructure for potential resistive switching applications","authors":"Pukhraj Prajapat, Pargam Vashishtha, Preeti Goswami, Govind Gupta","doi":"10.1088/2632-959x/ad1695","DOIUrl":"https://doi.org/10.1088/2632-959x/ad1695","url":null,"abstract":"The exponential growth of large data and the widespread adoption of the Internet of Things (IoT) have created significant challenges for traditional Von Neumann computers. These challenges include complex hardware, high energy consumption, and slow memory access time. Researchers are investigating novel materials and device architectures to address these issues by reducing energy consumption, improving performance, and enabling compact designs. A new study has successfully engineered a heterostructure that integrates Sb<sub>2</sub>Se<sub>3</sub> and Sb<sub>2</sub>S<sub>3</sub>, resulting in improved electrical properties. This has generated significant interest in its potential applications in resistive switching. In this study, we have demonstrated the fabrication of a device based on Sb<sub>2</sub>S<sub>3</sub>/Sb<sub>2</sub>Se<sub>3</sub> heterostructure that exhibits resistive switching behavior. The device has different resistance states that can be switched between high and low resistance levels when exposed to an external bias (−1 V to 0 V to 1 V). It also has good non-volatile memory characteristics, including low power consumption, high resistance ratio (∼10<sup>2</sup>), and reliable endurance (∼10<sup>3</sup>). The device enables faster data processing, reduces energy consumption, and streamlines hardware designs, contributing to computing advancements amidst modern challenges. This approach can revolutionize resistive switching devices, leading to more efficient computing solutions for big data processing and IoT technologies.","PeriodicalId":501827,"journal":{"name":"Nano Express","volume":"11 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139092807","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}
MoS2/TiO2 nanostructure provides a lot of advantages in photoelectrochemical (PEC) applications due to the absorption of the wide spectrum solar radiation, more catalytically active sites, proper band alignment, and better separation of photogenerated charge carriers. Here we report PEC water splitting studies of MoS2 thin film grown by chemical vapor deposition on TiO2 nanotubes fabricated on flexible thin Ti foil. Raman and x-ray diffraction analysis confirmed the polycrystalline growth of a few layers MoS2 on TiO2/Ti through their characteristic peaks. Field emission scanning electron microscopy revealed the nanotube surface morphology of TiO2 having a diameter in the range of 200–300 nm. The chemical and electronic composition of MoS2 and TiO2 were investigated by x-ray photoelectron spectroscopy. PEC measurements performed in 0.5 M Na2SO4 aqueous electrolyte solution under 100 mW cm−2 (AM 1.5G) simulated sunlight revealed 2-fold improved photocurrent density for MoS2/TiO2 heterostructure (∼135.7 μA cm−2) compared to that of bare TiO2 (∼70 μA cm−2). This is attributed to extended light absorption and more catalytically active surface area resulting from MoS2 functionalization of the TiO2 nanotubes, which results in better PEC activity. This study provides a new insight to explore the performance of thin metal foil-based photoelectrode in PEC applications that can be beneficial to develop roll-to-roll device fabrication to advance futuristic flexible electronics.
{"title":"MoS2 thin film decorated TiO2 nanotube arrays on flexible Ti foil for solar water splitting application","authors":"Bheem Singh, Sudhanshu Gautam, Govinda Chandra Behera, Rahul Kumar, Vishnu Aggarwal, Jai Shankar Tawale, Ramakrishnan Ganesan, Somnath Chanda Roy, Sunil Singh Kushvaha","doi":"10.1088/2632-959x/ad1694","DOIUrl":"https://doi.org/10.1088/2632-959x/ad1694","url":null,"abstract":"MoS<sub>2</sub>/TiO<sub>2</sub> nanostructure provides a lot of advantages in photoelectrochemical (PEC) applications due to the absorption of the wide spectrum solar radiation, more catalytically active sites, proper band alignment, and better separation of photogenerated charge carriers. Here we report PEC water splitting studies of MoS<sub>2</sub> thin film grown by chemical vapor deposition on TiO<sub>2</sub> nanotubes fabricated on flexible thin Ti foil. Raman and x-ray diffraction analysis confirmed the polycrystalline growth of a few layers MoS<sub>2</sub> on TiO<sub>2</sub>/Ti through their characteristic peaks. Field emission scanning electron microscopy revealed the nanotube surface morphology of TiO<sub>2</sub> having a diameter in the range of 200–300 nm. The chemical and electronic composition of MoS<sub>2</sub> and TiO<sub>2</sub> were investigated by x-ray photoelectron spectroscopy. PEC measurements performed in 0.5 M Na<sub>2</sub>SO<sub>4</sub> aqueous electrolyte solution under 100 mW cm<sup>−2</sup> (AM 1.5G) simulated sunlight revealed 2-fold improved photocurrent density for MoS<sub>2</sub>/TiO<sub>2</sub> heterostructure (∼135.7 <italic toggle=\"yes\">μ</italic>A cm<sup>−2</sup>) compared to that of bare TiO<sub>2</sub> (∼70 <italic toggle=\"yes\">μ</italic>A cm<sup>−2</sup>). This is attributed to extended light absorption and more catalytically active surface area resulting from MoS<sub>2</sub> functionalization of the TiO<sub>2</sub> nanotubes, which results in better PEC activity. This study provides a new insight to explore the performance of thin metal foil-based photoelectrode in PEC applications that can be beneficial to develop roll-to-roll device fabrication to advance futuristic flexible electronics.","PeriodicalId":501827,"journal":{"name":"Nano Express","volume":"35 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139092440","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}
Pub Date : 2023-12-08DOI: 10.1088/2632-959x/ad100b
Ghulam Abbas Gohar, Awais Akhtar, Hassan Raza, Ghulam Mustafa, Mahreen Fatima, Habib Ur Rehman, Muhammad Waqas Aslam, Abrar ul Haq, Waqar Manzoor
Polymeric nanocomposites have emerged as a promising class of materials with improved strength, stiffness, and toughness compared to pure polymers. The incorporation of nanoparticles into polymer matrices, such as carbon nanotubes, graphene, clay nanoparticles, and metal oxides, has shown considerable potential for enhancing the properties of the produced nanocomposites. Herein, the influence of filtered multiwalled carbon nanotubes (MWCNTs) on solution-cast polyurethane (PU) nanocomposite is explored. Scanning electron microscopy (SEM), x-ray diffraction (XRD), Raman spectroscopy, thermogravimetric analysis (TGA), and x-rays photoelectron spectroscopy (XPS), respectively, were employed to characterize the morphology, crystal structure, phase, thermal stability, and oxidation states of the samples. MWCNTs with a higher weight% of MWCNTs showcased superior mechanical properties compared to base polymer (PU). The nanocomposite with 1 wt% of MWCNTs and 99 wt% of PU exhibited the highest stress (19.25 N mm−2) and strain (700.22%) among all fabricated samples. Also, Modulus of elasticity (∼25%), Ultimate tensile strength (∼21%), and elongation at break (∼11%) are increased by incorporating 0.5 wt% MWCNTs into PU matrix. The attainment of these remarkable mechanical properties could be attributed to excellent dispersion, interfacial bonding and structural stability of filtered MWCNTs in the nanocomposites.
与纯聚合物相比，聚合物纳米复合材料具有更高的强度、刚度和韧性，是一种很有前途的材料。将纳米颗粒（如碳纳米管、石墨烯、粘土纳米颗粒和金属氧化物）掺入聚合物基体中，已显示出增强所生产的纳米复合材料性能的巨大潜力。本文探讨了过滤多壁碳纳米管（MWCNTs）对溶液浇注聚氨酯（PU）纳米复合材料的影响。分别采用扫描电子显微镜（SEM）、X 射线衍射（XRD）、拉曼光谱、热重分析（TGA）和 X 射线光电子能谱（XPS）来表征样品的形貌、晶体结构、相、热稳定性和氧化态。与基础聚合物（PU）相比，MWCNTs 重量百分比较高的纳米复合材料具有更优越的机械性能。在所有制成的样品中，MWCNTs 含量为 1 wt% 和 PU 含量为 99 wt% 的纳米复合材料表现出最高的应力（19.25 N mm-2）和应变（700.22%）。此外，在聚氨酯基体中加入 0.5 wt%的 MWCNTs 后，弹性模量（∼25%）、极限拉伸强度（∼21%）和断裂伸长率（∼11%）均有所提高。这些优异机械性能的获得可归因于纳米复合材料中过滤的 MWCNTs 具有优异的分散性、界面结合性和结构稳定性。
{"title":"Achieving enhanced tensile properties of polyurethane-multiwall carbon nanotubes nanocomposites","authors":"Ghulam Abbas Gohar, Awais Akhtar, Hassan Raza, Ghulam Mustafa, Mahreen Fatima, Habib Ur Rehman, Muhammad Waqas Aslam, Abrar ul Haq, Waqar Manzoor","doi":"10.1088/2632-959x/ad100b","DOIUrl":"https://doi.org/10.1088/2632-959x/ad100b","url":null,"abstract":"Polymeric nanocomposites have emerged as a promising class of materials with improved strength, stiffness, and toughness compared to pure polymers. The incorporation of nanoparticles into polymer matrices, such as carbon nanotubes, graphene, clay nanoparticles, and metal oxides, has shown considerable potential for enhancing the properties of the produced nanocomposites. Herein, the influence of filtered multiwalled carbon nanotubes (MWCNTs) on solution-cast polyurethane (PU) nanocomposite is explored. Scanning electron microscopy (<italic toggle=\"yes\">SEM</italic>), x-ray diffraction (<italic toggle=\"yes\">XRD</italic>), Raman spectroscopy, thermogravimetric analysis (<italic toggle=\"yes\">TGA</italic>), and x-rays photoelectron spectroscopy (<italic toggle=\"yes\">XPS</italic>), respectively, were employed to characterize the morphology, crystal structure, phase, thermal stability, and oxidation states of the samples. MWCNTs with a higher weight% of MWCNTs showcased superior mechanical properties compared to base polymer (PU). The nanocomposite with 1 wt% of MWCNTs and 99 wt% of PU exhibited the highest stress (19.25 N mm<sup>−2</sup>) and strain (700.22%) among all fabricated samples. Also, Modulus of elasticity (∼25%), Ultimate tensile strength (∼21%), and elongation at break (∼11%) are increased by incorporating 0.5 wt% MWCNTs into PU matrix. The attainment of these remarkable mechanical properties could be attributed to excellent dispersion, interfacial bonding and structural stability of filtered MWCNTs in the nanocomposites.","PeriodicalId":501827,"journal":{"name":"Nano Express","volume":"86 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-12-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138693344","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}
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