Statistical morphological identification of low-dimensional nanomaterials by using TEM

Nanomaterials with low-dimensional morphology display unique properties in catalysis and related fields,which are highly dependent on the structure and aspect ratio.Thus,accurate identification of the structure and morphology is the basis to correlate to the performance.However,the widely adopted techniques such as XRD is incapable to precise identify the aspect ratio of low-dimensional nanomaterials,not even to quantify the morphological uniformity with statistical deviation value.Herein,ZnO nanorod and nanosheet featured with one-and two-dimensional morphology were selected as model materials,which were prepared by the hydrothermal method and statistically characterized by transmission electron microscopy(TEM).The results indicate that ZnO nanorods and nanosheets display rod-like and orthohexagnal morphology,which mainly encapsulated with{100}and{001}planes,respectively.The 7.36±0.20 and 0.39±0.02 aspect ratio(c/a)of ZnO nanorods and nanosheets could be obtained through the integration of the(100)and(002)diffraction rings in selected area electron diffraction(SAED).TEM combining with the SAED is favorable compare with XRD,which not only provides more accurate aspect ratio results with standard deviation values but also requires very small amounts of sample.This work is supposed to provide a convenient and accurate method for the characterization of nanomaterials with low-dimensional morphology through TEM.

STRENGTH, PLASTICITY, INTERLAYER INTERACTIONS AND PHASE TRANSITION OF LOW-DIMENSIONAL NANOMATERIALS UNDER MULTIPLE FIELDS

Atoms are hold together to form different materials and devices through short range interactions such as chemical bonds and long range interactions such as the van der Waals force and electromagnetic interactions. Quantum mechanics is powerful to describe the short range interactions of materials at the nanometer scale, while molecular mechanics and dynamics based on empirical potentials are able to simulate material behaviors at much large scales, but weak in handling of processes including charge transfer and redistributions, such as mechanical-electric coupling of functional nanomaterials, plastic deformation~ fracture and phase transition of nano- materials. These issues are also challenging to quantum mechanics which needs to be extended to van der Waals distance and larger spatial as well as temporal scales. Here, we make brief review and discussions on such kind of mechanical behaviors of some important functional nanomaterials and nanostructures, to probe the frontier of nanomechanics and the trend to multiscale physical mechanics.

Recent progress on nanomaterial-based electrochemical dissolved oxygen sensors

Dissolved oxygen(DO)usually refers to the amount of oxygen dissolved in water.In the environment,medicine,and fermentation industries,the DO level needs to be accurate and capable of online monitoring to guide the precise control of water quality,clinical treatment,and microbial metabolism.Compared with other analytical methods,the electrochemical strategy is superior in its fast response,low cost,high sensitivity,and portable device.However,an electrochemical DO sensor faces a trade-off between sensitivity and long-term stability,which strongly limits its practical applications.To solve this problem,various advanced nanomaterials have been proposed to promote detection performance owing to their excellent electrocatalysis,conductivity,and chemical stability.Therefore,in this review,we focus on the recent progress of advanced nanomaterial-based electrochemical DO sensors.Through the comparison of the working principles on the main analysis techniques toward DO,the advantages of the electrochemical method are discussed.Emphasis is placed on recently developed nanomaterials that exhibit special characteristics,including nanostructures and preparation routes,to benefit DO determination.Specifically,we also introduce some interesting research on the configuration design of the electrode and device,which is rarely introduced.Then,the different requirements of the electrochemical DO sensors in different application fields are included to provide brief guidance on the selection of appropriate nanomaterials.Finally,the main challenges are evaluated to propose future development prospects and detection strategies for nanomaterial-based electrochemical sensors.

Laser spectroscopy imaging technique coupled withnanomaterials for cancer diagnosis: A review

Laser spectroscopic imaging techniques have received tremendous attention in the-eld of cancer diagnosis due to their high sensitivity,high temporal resolution,and short acquisition time.However,the limited tissue penetration of the laser is still a challenge for the in vivo diagnosis of deep-seated lesions.Nanomaterials have been universally integrated with spectroscopic imaging techniques for deeper cancer diagnosis in vivo.The components,morphology,and sizes of nanomaterials are delicately designed,which could realize cancer diagnosis in vivo or in situ.Considering the enhanced signal emitting from the nanomaterials,we emphasized their combination with spectroscopic imaging techniques for cancer diagnosis,like the surface-enhanced Raman scattering(SERS),photoacoustic,fluorescence,and laser-induced breakdown spectroscopy(LIBS).Applications ofthe above spectroscopic techniques offer new prospectsfor cancer diagnosis.

Carbon-based nanomaterials cause toxicity by oxidative stress to the liver and brain in Sprague-Dawley rats

Carbon-based nanomaterials have important research significance in various disciplines,such as composite materials,nanoelectronic devices,biosensors,biological imaging,and drug delivery.Recently,the human and ecological risks associated with carbon-based nanomaterials have received increasing attention.However,the biological safety of carbon based nanomaterials has not been systematically studied.In this study,we used different types of carbon materials,namely,graphene oxide(GO),single-walled carbon nanotubes(SWCNTs),and multiwalled carbon nanotubes(MWCNTs),as models to observe their distribution and oxidative damage in vivo.The results of Histopathological and ultrastructural examinations indicated that the liver and lungs were the main accumulation targets of these nanomaterials.SR-μ-XRF analysis revealed that SWCNTs and MWCNTs might be present in the brain.This shows that the three types of carbon-based nanomaterials could cross the gas-blood barrier and eventually reach the liver tissue.In addition,SWCNTs and MWCNTs could cross the blood-brain barrier and accumulate in the cerebral cortex.The increase in ROS and MDA levels and the decrease in GSH,SOD,and CAT levels indicated that the three types of nanomaterials might cause oxidative stress in the liver.This suggests that direct instillation of these carbon-based nanomaterials into rats could induce ROS generation.In addition,iron(Fe)contaminants in these nanomaterials were a definite source of free radicals.However,these nanomaterials did not cause obvious damage to the rat brain tissue.The deposition of selenoprotein in the rat brain was found to be related to oxidative stress and Fe deficiency.This information may support the development of secure and reasonable applications of the studied carbon-based nanomaterials.

Mapping the intellectual structure and emerging trends for the application of nanomaterials in gastric cancer:A bibliometric study

BACKGROUND Recent reviews have outlined the main nanomaterials used in relation to gastrointestinal tumors and described the basic properties of these materials.However,the research hotspots and trends in the application of nanomaterials in gastric cancer(GC)remain obscure.AIM To demonstrate the knowledge structure and evolutionary trends of research into the application of nanomaterials in GC.METHODS Publications related to the application of nanomaterials in GC were retrieved from the Web of Science Core Collection for this systematic review and bibliometric study.VOSviewer and CiteSpace were used for bibliometric and visualization analyses.RESULTS From 2000 to 2022,the application of nanomaterials in GC developed rapidly.The keyword co-occurrence analysis showed that the related research topics were divided into three clusters:(1)The application of nanomaterials in GC treatment;(2)The application and toxicity of nanomaterials in GC diagnosis;and(3)The effects of nanomaterials on the biological behavior of GC cells.Complexes,silver nanoparticles,and green synthesis are the latest high-frequency keywords that represent promising future research directions.CONCLUSION The application of nanomaterials in GC diagnosis and treatment and the mechanisms of their effects on GC cells have been major themes in this field over the past 23 years.

Nanomaterials-mediated lysosomal regulation:a robust protein-clearance approach for the treatment of Alzheimer’s disease

Alzheimer’s disease is a debilitating,progressive neurodegenerative disorder characterized by the progressive accumulation of abnormal proteins,including amyloid plaques and intracellular tau tangles,primarily within the brain.Lysosomes,crucial intracellular organelles responsible for protein degradation,play a key role in maintaining cellular homeostasis.Some studies have suggested a link between the dysregulation of the lysosomal system and pathogenesis of neurodegenerative diseases,including Alzheimer’s disease.Restoring the normal physiological function of lysosomes hold the potential to reduce the pathological burden and improve the symptoms of Alzheimer’s disease.Currently,the efficacy of drugs in treating Alzheimer’s disease is limited,with major challenges in drug delivery efficiency and targeting.Recently,nanomaterials have gained widespread use in Alzheimer’s disease drug research owing to their favorable physical and chemical properties.This review aims to provide a comprehensive overview of recent advances in using nanomaterials(polymeric nanomaterials,nanoemulsions,and carbon-based nanomaterials)to enhance lysosomal function in treating Alzheimer’s disease.This review also explores new concepts and potential therapeutic strategies for Alzheimer’s disease through the integration of nanomaterials and modulation of lysosomal function.In conclusion,this review emphasizes the potential of nanomaterials in modulating lysosomal function to improve the pathological features of Alzheimer’s disease.The application of nanotechnology to the development of Alzheimer’s disease drugs brings new ideas and approaches for future treatment of this disease.

Recent progress on Sn_(3)O_(4)nanomaterials for photocatalytic applications

Tin(IV)oxide(Sn_(3)O_(4))is layered tin and exhibits mixed valence states.It has emerged as a highly promising visible-light pho-tocatalyst,attracting considerable attention.This comprehensive review is aimed at providing a detailed overview of the latest advance-ments in research,applications,advantages,and challenges associated with Sn_(3)O_(4)photocatalytic nanomaterials.The fundamental con-cepts and principles of Sn_(3)O_(4)are introduced.Sn_(3)O_(4)possesses a unique crystal structure and optoelectronic properties that allow it to ab-sorb visible light efficiently and generate photoexcited charge carriers that drive photocatalytic reactions.Subsequently,strategies for the control and improved performance of Sn_(3)O_(4)photocatalytic nanomaterials are discussed.Morphology control,ion doping,and hetero-structure construction are widely employed in the optimization of the photocatalytic performance of Sn_(3)O_(4)materials.The effective imple-mentation of these strategies improves the photocatalytic activity and stability of Sn_(3)O_(4)nanomaterials.Furthermore,the review explores the diverse applications of Sn_(3)O_(4)photocatalytic nanomaterials in various fields,such as photocatalytic degradation,photocatalytic hydro-gen production,photocatalytic reduction of carbon dioxide,solar cells,photocatalytic sterilization,and optoelectronic sensors.The discus-sion focuses on the potential of Sn_(3)O_(4)-based nanomaterials in these applications,highlighting their unique attributes and functionalities.Finally,the review provides an outlook on the future development directions in the field and offers guidance for the exploration and de-velopment of novel and efficient Sn_(3)O_(4)-based nanomaterials.Through the identification of emerging research areas and potential avenues for improvement,this review aims to stimulate further advancements in Sn_(3)O_(4)-based photocatalysis and facilitate the translation of this promising technology into practical applications.

Preparation of Corncob-Like WO3 Nanomaterials and Their Photocatalytic Treatment of Toluene

Corn rod-like WO3 nanomaterials were successfully synthesized by a simple hydrothermal method. The morphology, structure and optical absorption properties of the prepared samples were characterized by SEM, XRD, FTIR and UV-Vis-DRS. The WO3 materials were corn rod-like morphology with about 800 nm for length and 150 nm for diameter, especially there were plenty of corn particles (about 20 nm) on the surface of corn rods. The X-ray diffraction peaks of the products corresponded with WO3 standard card, and the characteristic peak of W-O bond was found in the infrared spectrum. The absorption band edge of the products was about 480 nm, indicating their potential visible-light-induced photocatalytic activity. In situ FTIR technology research showed that the prepared WO3 nanomaterials had visible photocatalytic activity to gas-phase toluene. After a photocatalytic reaction for 8 hours toluene was effectively degraded, and carboxylic acid and aldehyde could be regarded as the intermediate products, and CO2 was produced as the final product during the reaction process.

Friction of low-dimensional nanomaterial systems

When material dimensions are reduced to the nanoscale,exceptional physical mechanics properties can be obtained that differ significantly from the corresponding bulk materials.Here we review the physical mechanics of the friction of low‐dimensional nanomaterials,including zero‐dimensional nanoparticles,one‐dimensional multiwalled nanotubes and nanowires,and two‐dimensional nanomaterials-such as graphene,hexagonal boron nitride(h‐BN),and transition‐metal dichalcogenides-as well as topological insulators.Nanoparticles between solid surfaces can serve as rolling and sliding lubrication,while the interlayer friction of multiwalled nanotubes can be ultralow or significantly high and sensitive to interwall spacing and chirality matching,as well as the tube materials.The interwall friction can be several orders of magnitude higher in binary polarized h‐BN tubes than in carbon nanotubes mainly because of wall buckling.Furthermore,current extensive studies on two‐dimensional nanomaterials are comprehensively reviewed herein.In contrast to their bulk materials that serve as traditional dry lubricants(e.g.,graphite,bulk h‐BN,and MoS_(2)),large‐area high‐quality monolayered two‐dimensional nanomaterials can serve as single‐atom‐thick coatings that minimize friction and wear.In addition,by appropriately tuning the surface properties,these materials have shown great promise for creating energy‐efficient self‐powered electro‐opto‐magneto‐mechanical nanosystems.State‐of‐the‐art experimental and theoretical methods to characterize friction in nanomaterials are also introduced.

Low-dimensional nanomaterial/Si heterostructure-based photodetectors

Due to its excellent electrical and optical features,silicon(Si)is highly attractive for photodetector applications.The design and fabrication of low-dimensional semiconductor/Si hybrid heterostructures provide a great platform for fabricating high-performance photodetectors,thereby overcoming the inherent limitations of Si.This review focuses on state-of-the-art Si heterostructure-based photodetectors.It starts with the introduction of three different device configurations,that is,photoconductors,photodiodes,and phototransistors.Their working mechanisms and relative pros and cons are introduced,and the figures of merit of photodetectors are summarized.Then,we discuss the device physics/design,photodetection performance,and optimization strategies for Si-based photodetectors.Finally,future challenges in the photodetector applications of Si-based hybrid heterostructures are discussed.

Preparation,Properties,and Applications of Low-Dimensional Molecular Organic Nanomaterials

In recent years, great progress has been made in research and development of small-molecule organic materials with various low-dimensional nanostructures. This paper presents a comprehensive review of recent research progress in this field, including preparation, electronic and optoelectronic properties and applications. First, an introduction gives to the reprecipitation, soft templates methods, and progress in synthesis and morphological control of low-dimensional small-molecule organic nanomaterials. Their unique optical and electronic properties and research progress in these aspects are reviewed and discussed in detail. Applications based on low-dimensional small-molecule organic nanomaterials are briefly described. Finally, some perspectives to the future development of this field are addressed.

Synthesis of porous carbon nanomaterials and their application in tetracycline removal from aqueous solutions

The low-cost and efficient elimination of tetracycline from wastewater and to decrease the concentration in soils,sediments,rivers,underground water,or lakes are crucial to human health.Herein,threedimensional porous carbon nanomaterials were synthesized using glucose and NH_(4)Cl by sugarblowing process at 900℃ and then oxidized under air atmosphere for surface functional group modification.The prepared 3D porous carbon nanomaterials were applied for the removal of tetracycline from aqueous solutions.The sorption isotherms were well simulated by the Langmuir model,with the calculated sorption capacity of 2378 mg·g^(-1) for C-450 at pH=6.5,which was the highest value of today's reported materials.The porous carbon nanomaterials showed high stability at acidic conditions and selectivity in high salt concentrations.The good recycle ability and high removal efficiency of tetracycline from natural groundwater indicated the potential application of the porous carbon nanomaterials in natural environmental antibiotic pollution cleanup.The outstanding sorption properties were attributed to the structures,surface areas and functional groups,strong interactions such as H-bonding,π-π interaction,electrostatic attraction,etc.This paper highlighted the synthesis of porous carbon nanomaterials with high specific surfaces,high sorption capacities,stability,and reusability in organic chemicals'pollution treatment.

Diagnosis and treatment of chronic osteomyelitis based on nanomaterials

Chronic osteomyelitis is a painful and serious disease caused by infected surgical prostheses or infected fractures.Traditional treatment includes surgical debridement followed by prolonged systemic antibiotics.However,excessive antibiotic use has been inducing rapid emergence of antibiotic-resistant bacteria worldwide.Additionally,it is difficult for antibiotics to penetrate internal sites of infection such as bone,thus limiting their efficacy.New approaches to treat chronic osteomyelitis remain a major challenge for orthopedic surgeons.Luckily,the development of nanotechnology has brought new antimicrobial options with high specificity to infection sites,offering a possible way to address these challenges.Substantial progress has been made in constructing antibacterial nanomaterials for treatment of chronic osteomyelitis.Here,we review some current strategies for treatment of chronic osteomyelitis and their underlying mechanisms.

Low-dimensional perovskite modified 3D structures for higher-performance solar cells

For solution prepared perovskite solar cells,metal halide perovskite materials with low-dimensional(LD)are flexibly employed in 3D perovskite solar cells to promote efficiency and long-term stability.In this review,the various structures,properties,and applications of LD perovskites are firstly summarized and discussed.To take advantage of LD materials,LD perovskites are introduced in the 3D bulk and/or the interface between the perovskite thin film and the carrier transporting layer to passivate the gain boundary defects while providing the stability advantage of LD materials.Therefore,the preparation methods and crystallization control of the LD perovskite layers are discussed in depth.Then,the combined devices using both LD and 3D components are reviewed on the basis of device design,cell structure,interface charge transfer,energy lever alignment,and synergistic improvement of both efficiency and stability.Finally,the challenges and expectations are speculated for further development of perovskite solar cells.

Machine Learning-Assisted Low-Dimensional Electrocatalysts Design for Hydrogen Evolution Reaction

Efficient electrocatalysts are crucial for hydrogen generation from electrolyzing water.Nevertheless,the conventional"trial and error"method for producing advanced electrocatalysts is not only cost-ineffective but also time-consuming and labor-intensive.Fortunately,the advancement of machine learning brings new opportunities for electrocatalysts discovery and design.By analyzing experimental and theoretical data,machine learning can effectively predict their hydrogen evolution reaction(HER)performance.This review summarizes recent developments in machine learning for low-dimensional electrocatalysts,including zero-dimension nanoparticles and nanoclusters,one-dimensional nanotubes and nanowires,two-dimensional nanosheets,as well as other electrocatalysts.In particular,the effects of descriptors and algorithms on screening low-dimensional electrocatalysts and investigating their HER performance are highlighted.Finally,the future directions and perspectives for machine learning in electrocatalysis are discussed,emphasizing the potential for machine learning to accelerate electrocatalyst discovery,optimize their performance,and provide new insights into electrocatalytic mechanisms.Overall,this work offers an in-depth understanding of the current state of machine learning in electrocatalysis and its potential for future research.

Two-dimensional silicon nanomaterials for optoelectronics

Silicon nanomaterials have been of immense interest in the last few decades due to their remarkable optoelectronic responses,elemental abundance,and higher biocompatibility.Two-dimensional silicon is one of the new allotropes of silicon and has many compelling properties such as quantum-confined photoluminescence,high charge carrier mobilities,anisotropic electronic and magnetic response,and non-linear optical properties.This review summarizes the recent advances in the synthesis of two-dimensional silicon nanomaterials with a range of structures(silicene,silicane,and multilayered silicon),surface ligand engineering,and corresponding optoelectronic applications.

Applications of nanomaterials in mosquito vector control:A review

The periodic outbreak of mosquito-borne diseases like dengue fever,zika fever,and yellow fever all over the world highlights the need for effective mosquito control methods targeting the biological system.Due to the lack of therapeutic measures,preventive treatments or vaccines against pathogens,insecticide resistance eventually lead the research focus towards novel technological applications in mosquito management.Nanomaterials with ovicidal,larvicidal,adulticidal,and repellent properties for controlling mosquito vectors are under research.A literature search was carried out for advancements in nanomaterials,insecticides,and mosquito control in PubMed/MEDLINE,Scopus,Google Scholar,ScienceDirect,and Web of Science.This paper aims to provide insights into various nanomaterials relevant to mosquito-borne diseases,in vivo and in vitro toxicity evaluation against mosquito species,mode of action,effect on non-target organisms,and ecological risks.Organic and inorganic materials that provide controlled release,target delivery,less dosage,prolonged efficacy,a reduction in the use of organic solvents and emulsifiers,and minimum pollution to the environment have already been explored.Indeed,further research on the ecological risk and economic feasibility of nanomaterials in mosquitocidal applications should be done prior to commercialization.

Circularly Polarized Light-Enabled Chiral Nanomaterials:From Fabrication to Application

For decades,chiral nanomaterials have been extensively studied because of their extraordinary properties.Chiral nanostructures have attracted a lot of interest because of their potential applications including biosensing,asymmetric catalysis,optical devices,and negative index materials.Circularly polarized light(CPL)is the most attractive source for chirality owing to its high availability,and now it has been used as a chiral source for the preparation of chiral matter.In this review,the recent progress in the field of CPL-enabled chiral nanomaterials is summarized.Firstly,the recent advancements in the fabrication of chiral materials using circularly polarized light are described,focusing on the unique strategies.Secondly,an overview of the potential applications of chiral nanomaterials driven by CPL is provided,with a particular emphasis on biosensing,catalysis,and phototherapy.Finally,a perspective on the challenges in the field of CPL-enabled chiral nanomaterials is given.

Progress in oncolytic viruses modified with nanomaterials for intravenous application

In oncolytic virus(OV)therapy,a critical component of tumor immunotherapy,viruses selectively infect,replicate within,and eventually destroy tumor cells.Simultaneously,this therapy activates immune responses and mobilizes immune cells,thereby eliminating residual or distant cancer cells.However,because of OVs’high immunogenicity and immune clearance during circulation,their clinical applications are currently limited to intratumoral injections,and their use is severely restricted.In recent years,numerous studies have used nanomaterials to modify OVs to decrease virulence and increase safety for intravenous injection.The most commonly used nanomaterials for modifying OVs are liposomes,polymers,and albumin,because of their biosafety,practicability,and effectiveness.The aim of this review is to summarize progress in the use of these nanomaterials in preclinical experiments to modify OVs and to discuss the challenges encountered from basic research to clinical application.