Nano FuturesPub Date : 2022-01-24DOI: 10.1088/2399-1984/ac4e77
K. Boldt
{"title":"Raman spectroscopy of colloidal semiconductor nanocrystals","authors":"K. Boldt","doi":"10.1088/2399-1984/ac4e77","DOIUrl":"https://doi.org/10.1088/2399-1984/ac4e77","url":null,"abstract":"Raman spectroscopy is a powerful method that gives insight into the atomic structure and composition of nanomaterials, but also allows to draw conclusions about their electronic properties. It is based on the inelastic scattering of light, which is able to excite phonons in the material. In the field of semiconductor nanocrystals, Raman spectroscopy has been employed to make significant contributions to the analysis of lattice distortion, interfaces, phase mixing, and defect formation. Yet, there is no clear consensus on how the electronic and crystal structure of the material interacts with the incident light to yield the observed spectra. This review gives a brief overview over the method. It then reviews the most important findings, current developments, and discusses the efforts to formulate a consistent model that allows to establish the method as a tool for structural analysis.","PeriodicalId":54222,"journal":{"name":"Nano Futures","volume":null,"pages":null},"PeriodicalIF":2.1,"publicationDate":"2022-01-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47530025","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Nano FuturesPub Date : 2022-01-11DOI: 10.1088/2399-1984/ac4a27
O. Konevtsova, D. Roshal, S. Rochal
{"title":"Moiré patterns and carbon nanotube sorting","authors":"O. Konevtsova, D. Roshal, S. Rochal","doi":"10.1088/2399-1984/ac4a27","DOIUrl":"https://doi.org/10.1088/2399-1984/ac4a27","url":null,"abstract":"Moiré patterns (MPs), arising from the superposition of two lattices with close periods, are tightly related to the physicochemical properties of bilayer nanostructures. Here, we develop the theory of complex MPs emerging in twisted bilayer graphene and planar nets of double-walled nanotubes at significant relative twist and/or deformation of layers. The proposed theory clarifies the physicochemical regularities arising at sorting of single-walled carbon nanotubes (SWCNTs) by organic molecules, which self-assemble in regular coatings on both the tubes and planar graphene. We introduce and consider an outer tubular virtual lattice that is a parent structure for the deposited coating and due to this fact, its existence is crucial for the coating formation. As we show, such outer lattices exist only for successfully sorted SWCNTs and the superposition between the outer lattice and SWCNT forms a specific long-period MP. We explain known experimental results of SWCNT sorting by molecules of flavin group, poly(9,9-dioctylfluorene-2,7-diyl), and poly [(m-phenylenevinylene)-alt-(p-phenylenevinylene)]. Also, our approach points out other organic molecules and polymers suitable for effective carbon nanotube sorting.","PeriodicalId":54222,"journal":{"name":"Nano Futures","volume":null,"pages":null},"PeriodicalIF":2.1,"publicationDate":"2022-01-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45710646","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Nano FuturesPub Date : 2021-12-17DOI: 10.1088/2399-1984/ac446c
F. A. Jan, Wajidullah, R. Ullah, Salman, N. Ullah, A. Salam
{"title":"An investigation into the environmental and therapeutic applications of holmium-doped titanium dioxide (Ho-TiO2) nanocatalysts: a kinetic and thermodynamic study of the photocatalytic degradation of Safranin O dye","authors":"F. A. Jan, Wajidullah, R. Ullah, Salman, N. Ullah, A. Salam","doi":"10.1088/2399-1984/ac446c","DOIUrl":"https://doi.org/10.1088/2399-1984/ac446c","url":null,"abstract":"Titanium dioxide (TiO2) and holmium-doped titanium dioxide (Ho-TiO2) nanoparticles(NPs) were synthesized through a sol gel route. The synthesized NPs were characterized by ultraviolet-visible (UV–Vis) spectroscopy, x-ray diffraction (XRD), energy dispersive x-ray analysis, scanning electron microscopy (SEM), Fourier transform infrared spectroscopy, and photoluminescence (PL) spectroscopy. DNA binding, antibacterial, hemolysis, and antioxidant assays of the synthesized NPs were also carried out in order to find their therapeutic applications. Successful doping of TiO2 with Ho reduced the bandgap from 3.10 to 2.88 eV. SEM and XRD analysis showed that both TiO2 and Ho-TiO2 NPs exhibit a tetragonal structure and the morphology of the particles improved and agglomeration reduced as a result of doping. The PL emission intensity of TiO2 also reduced with doping. The degradation of Safranin O dye over both the catalysts followed first-order kinetics. The calculated activation energy for the photodegradation of the given dye was found to be 51.7 and 35.2 KJ mol−1 for bare TiO2 and Ho-TiO2 NPs, respectively. After 180 min, 84% and 87% dye degradation was observed using pure TiO2 and Ho-TiO2, respectively. A high percent of degradation of the dye was found at a low concentration (20 ppm) and at optimal dosage (0.035 g) of both the catalysts. The rate of Safranin O dye degradation was found to increase with an increase in temperature and pH of the medium. A DNA binding study revealed that Ho-TiO2 NPs are more capable of binding to human DNA. An antibacterial activity study showed that Ho-TiO2 NPs were more efficient against both gram-negative and gram-positive bacterial strains compared to pure TiO2. Hemolysis assay showed that TiO2 and Ho-TiO2 NPs are non-biocompatible. Ho-TiO2 NPs showed higher anti-oxidant activity compared to bare TiO2.","PeriodicalId":54222,"journal":{"name":"Nano Futures","volume":null,"pages":null},"PeriodicalIF":2.1,"publicationDate":"2021-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47681698","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Nano FuturesPub Date : 2021-12-10DOI: 10.1088/2399-1984/ac421c
Huiwen Chen, Yunlong Li, Bo Zhao, Jun Ming, D. Xue
{"title":"Nanocrystals of metal halide perovskites and their analogues as scintillators for x-ray detection","authors":"Huiwen Chen, Yunlong Li, Bo Zhao, Jun Ming, D. Xue","doi":"10.1088/2399-1984/ac421c","DOIUrl":"https://doi.org/10.1088/2399-1984/ac421c","url":null,"abstract":"Scintillators are widely used for x-ray detection in various fields, such as medical diagnostics, industrial inspection and homeland security. Nanocrystals (NCs) of metal halide perovskites (MHPs) and their analogues showed great advantages as x-ray scintillators due to their cheap manufacturing, fast decay time, and room temperature scintillation from quantum confinement effect. However, there are still many challenges unsolved for further industrialization. Herein, it is necessary to summarize the progress of scintillators based on NCs of MHPs and their analogues. In the first section, the scintillation mechanism and key parameters are outlined. Then, various NCs of MHPs and their analogues used as scintillators are reviewed. Finally, the challenges and outlook are discussed. It is believed that NCs of MHPs and their analogues are favorable for large-area and flexible x-ray detectors.","PeriodicalId":54222,"journal":{"name":"Nano Futures","volume":null,"pages":null},"PeriodicalIF":2.1,"publicationDate":"2021-12-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49113038","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Nano FuturesPub Date : 2021-12-01DOI: 10.1088/2399-1984/ac279b
K. Samrat, M. Chandraprabha, R. Hari Krishna, R. Sharath, B. Harish
{"title":"Biogenic synthesis of nano-sulfur using Punica granatum fruit peel extract with enhanced antimicrobial activities for accelerating wound healing","authors":"K. Samrat, M. Chandraprabha, R. Hari Krishna, R. Sharath, B. Harish","doi":"10.1088/2399-1984/ac279b","DOIUrl":"https://doi.org/10.1088/2399-1984/ac279b","url":null,"abstract":"Microbial wound infections leading to secondary complications in wound healing has resulted in high demand for therapeutic drugs with improved efficacy. Despite achieving enhanced bio-activity and higher bioavailability compared to its bulk form, nano-sulfur (SNP) has been explored to a very limited extent for wound healing applications. In this work, we prepare biogenic SNP (SNP-B) via simple biogenic technique using pomegranate (Punica granatum) peel extract and demonstrate its antimicrobial and wound healing activity. The SNP-B was characterized using powder x-ray diffractometer, FESEM, transmission electron microscopy and Raman spectroscopy. Different wound models (excision, incision, dead space and burn) were used to assess the wound healing potential of SNP-B. The 2% (w/w) SNP-B treated group exhibited enhanced wound contraction rate (excision wound, 99.62 ± 0.59%; burn wound, 99.46 ± 0.59%), breaking strength (393.2 ± 10.87 g cm−2), and granulation tissue weight (166.8 ± 9.45 mg) compared to the control group (excision wound, 84.24 ± 2.78%; burn wound, 90.58 ± 3.2%; breaking strength, 241.3 ± 16.11 g cm−2; granulation tissue weight, 91.17 ± 7.28 mg). The efficacy of 2% (w/w) SNP-B was comparable to that of standard (5% w/w povidone-iodine ointment) in all the wound models analyzed. The SNP-B showed enhanced antibacterial activity with a MIC value of 90, 80, 80, and 60 μg ml−1 for Pseudomonas aeruginosa, Escherichia coli, Bacillus subtilis and Staphylococcus aureus, respectively. The results obtained prove the potential of SNP-B as a multifunctional therapeutic agent for topical applications.","PeriodicalId":54222,"journal":{"name":"Nano Futures","volume":null,"pages":null},"PeriodicalIF":2.1,"publicationDate":"2021-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44367413","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Nano FuturesPub Date : 2021-12-01DOI: 10.1088/2399-1984/ac421d
K. Murata, S. Yagi, Takashi Kanazawa, S. Tsubomatsu, C. Kirkham, K. Nittoh, D. Bowler, K. Miki
{"title":"Activation of two dopants, Bi and Er in δ-doped layer in Si crystal","authors":"K. Murata, S. Yagi, Takashi Kanazawa, S. Tsubomatsu, C. Kirkham, K. Nittoh, D. Bowler, K. Miki","doi":"10.1088/2399-1984/ac421d","DOIUrl":"https://doi.org/10.1088/2399-1984/ac421d","url":null,"abstract":"Conventional doping processes are no longer viable for realizing extreme structures, such as a δ-doped layer with multiple elements, such as the heavy Bi, within the silicon crystal. Here, we demonstrate the formation of (Bi + Er)-δ-doped layer based on surface nanostructures, i.e. Bi nanolines, as the dopant source by molecular beam epitaxy. The concentration of both Er and Bi dopants is controlled by adjusting the amount of deposited Er atoms, the growth temperature during Si capping and surfactant techniques. Subsequent post-annealing processing is essential in this doping technique to obtain activated dopants in the δ-doped layer. Electric transport measurement and photoluminescence study revealed that both Bi and Er dopants were activated after post-annealing at moderate temperature.","PeriodicalId":54222,"journal":{"name":"Nano Futures","volume":null,"pages":null},"PeriodicalIF":2.1,"publicationDate":"2021-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46133403","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Nano FuturesPub Date : 2021-11-30DOI: 10.1088/2399-1984/ac3ec1
X. Lei, Bo Liu, Payam Ahmadian Koudakan, Hongge Pan, Yitai Qian, Gongming Wang
{"title":"Single-atom catalyst cathodes for lithium–oxygen batteries: a review","authors":"X. Lei, Bo Liu, Payam Ahmadian Koudakan, Hongge Pan, Yitai Qian, Gongming Wang","doi":"10.1088/2399-1984/ac3ec1","DOIUrl":"https://doi.org/10.1088/2399-1984/ac3ec1","url":null,"abstract":"Recently, single-atom catalysts (SACs) have been found to be promising candidates for oxygen electrocatalysis in rechargeable lithium–oxygen batteries (LOBs) owing to their high oxygen electrocatalytic activity and high stability, which originates from their unique coordination environments and electronic properties. As a new type of catalyst for LOBs, the advancements have never been reviewed and discussed comprehensively. Herein, breakthroughs in the design of various types of SACs as cathode catalysts for LOBs are summarized, including Co-based, Ru-based, and other types of SACs. Moreover, considerable emphasis is placed on the correlations between the structural feature of the SAC active sites and the electrocatalytic performance of LOBs. Finally, an overview and challenges of SACs for practical LOBs are also provided. This review provides an intensive understanding of SACs for designing efficient oxygen electrocatalysis and offers useful guidelines for the development of SACs in the field of LOBs.","PeriodicalId":54222,"journal":{"name":"Nano Futures","volume":null,"pages":null},"PeriodicalIF":2.1,"publicationDate":"2021-11-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46627499","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Nano FuturesPub Date : 2021-11-25DOI: 10.1088/2399-1984/ac3d6e
Molood Barmala, M. Behnood
{"title":"Novel ternary metal oxide nanoparticles (La2Cu0.8Zn0.2O4) as a potential photocatalyst for visible light photocatalytic degradation of methylene blue and desulfurization of dibenzothiophene","authors":"Molood Barmala, M. Behnood","doi":"10.1088/2399-1984/ac3d6e","DOIUrl":"https://doi.org/10.1088/2399-1984/ac3d6e","url":null,"abstract":"In this work we present the preparation of novel ternary metal oxide nanoparticles, La2Cu0.8Zn0.2O4 (LCZO), using a simple co-precipitation method. The crystalline structure, morphology and composition of the prepared LCZO nanoparticles were characterized by x-ray diffraction, scanning electron microscopy and energy-dispersive x-ray analysis. The diffuse reflectance spectrum investigation showed that LCZO nanoparticles have considerable light absorption in the visible light region. Also, the LCZO nanoparticles possess a band-gap energy of 2.82 eV. To investigate the visible light photocatalytic potential of the prepared LCZO nanoparticles, two photocatalytic reactions were conducted, namely degradation of methylene blue (MB) solution and desulfurization of dibenzothiophene (DBT). In the presence of a 3:1 molar ratio of H2O2/DBT, a high photocatalytic desulfurization rate of DBT (93.7%) was obtained over 0.2 g of LCZO photocatalyst. In addition, the photocatalytic degradation rate of MB solution was 91.4%. The mechanisms of both photocatalytic reactions were studied using different radical scavenging agents, which showed that hydroxyl radicals are responsible for highly efficient desulfurization and degradation reactions. Moreover, reusability experiments reveal that the prepared LCZO photocatalyst has great stability and recyclability for both desulfurization of DBT and degradation of MB after six reaction cycles.","PeriodicalId":54222,"journal":{"name":"Nano Futures","volume":null,"pages":null},"PeriodicalIF":2.1,"publicationDate":"2021-11-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46645511","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Nano FuturesPub Date : 2021-11-24DOI: 10.1088/2399-1984/ac3ccd
Xin Kuang, Bifeng Yin, Xiping Yang, H. Jia, Bo Xu
{"title":"Study of the tribological properties of nano lubricating oil blends for diesel engines","authors":"Xin Kuang, Bifeng Yin, Xiping Yang, H. Jia, Bo Xu","doi":"10.1088/2399-1984/ac3ccd","DOIUrl":"https://doi.org/10.1088/2399-1984/ac3ccd","url":null,"abstract":"The aim of this paper is to evaluate and compare the tribological properties of lubricating oil blends with added nano graphene and nano cerium oxide (CeO2) on the key friction pairs of diesel engines. Dispersion stability is the premise of the study of tribological properties. In this paper, nano CeO2 particles were self-made and high-quality nano graphene was purchased. The dispersion stability of the two nanomaterials in lubricating oil was studied after the same modification. According to the working conditions of the cylinder liner and piston ring, friction and wear tests of the lubricating oil blends containing the modified nanomaterials were carried out at different temperatures. The results showed that both nanomaterials were successfully modified with oleic acid and stearic acid. The dispersion stability of the modified nanomaterials in lubricating oil was improved. The dispersion stability of the lubricating oil blends with graphene before and after modification was slightly higher than that of lubricating oil blends with CeO2 before and after modification. At high temperature, the anti-friction properties of the two nano lubricating oil blends were similar. At ambient temperature, lubricating oil blends containing modified CeO2 did not play a role in reducing friction, while lubricating oil blends with modified graphene had the effect of reducing friction. Whether at ambient temperature or high temperature, the anti-wear property when lubricated with lubricating oil blends with modified CeO2 within the right concentration range was better than that when lubricated with lubricating oil blends containing modified graphene.","PeriodicalId":54222,"journal":{"name":"Nano Futures","volume":null,"pages":null},"PeriodicalIF":2.1,"publicationDate":"2021-11-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43311682","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Nano FuturesPub Date : 2021-11-24DOI: 10.1088/2399-1984/ac3ccc
G. Zeevi, Joanna Dehnel, Adam K. Budniak, Y. Milyutin, G. Ankonina, H. Haick, E. Lifshitz, Y. Yaish
{"title":"Dynamics of light-induced charge transfer between carbon nanotube and CdSe/CdS core/shell nanocrystals","authors":"G. Zeevi, Joanna Dehnel, Adam K. Budniak, Y. Milyutin, G. Ankonina, H. Haick, E. Lifshitz, Y. Yaish","doi":"10.1088/2399-1984/ac3ccc","DOIUrl":"https://doi.org/10.1088/2399-1984/ac3ccc","url":null,"abstract":"The integration of semiconducting colloidal nanocrystals (NCs) with carbon nanotubes (CNTs) in a single device presents a unique platform that combines optical flexibility with high charge carrying capability. These qualities are desirable in many applications such as photovoltaic cells, photocatalysis, and light sensors. Here, we present hybrid devices that incorporate various CdSe/CdS core/shell NCs, such as seeded quantum dots and asymmetric seeded nanorods (a-sNRs), with a single-wall CNT in a field-effect transistor geometry. We used electrical measurements to probe a light-induced charge transfer (LICT) between the CdSe/CdS NCs and the CNT. We investigate the effect of gate voltage on the LICT magnitude and temporal characteristics. Surprisingly, the measured photo-response depends on the gate voltage, and we observe both electrons and holes transfer from the a-sNRs to the CNT. Furthermore, a comparison between LICT measurements on different devices with different CNTs and NC types reveals that the charge transfer time is directly proportional to the shell-thickness around the CdSe core and inversely correlated with the NCs size. The recovery of the charge trapped inside the CdSe/CdS NCs is characterized by two distinct fast and slow relaxation times, which depend on the NCs size and CNT type. Although, the charge relaxation time is similar between the symmetric QDs and the asymmetric sNRs, the overall percentage of the remaining charge in the QDs is significantly larger than in the sNRs. Understanding both gate voltage and NCs size effect on the LICT processes can optimize the performance of optoelectronic devices.","PeriodicalId":54222,"journal":{"name":"Nano Futures","volume":null,"pages":null},"PeriodicalIF":2.1,"publicationDate":"2021-11-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47890798","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}