Littérature scientifique sur le sujet « Semiconducting Polymer Nanomaterials »

Nanomaterials due to their size (ranging from 0.1-100 nm, at least in one dimension) and higher ratio of surface area to volume display dominant quantum effects causing drastic changes in their chemical reactivity as well as optical, elastic, electrical and magnetic properties. The electrons due to their wave nature move very easily without scattering in nanomaterials and allow their use as biological sensors. Nano wires, semiconducting in nature, act as a versatile optoelectronic component in photodetectors sensitive to polarization and arrays with sub wavelength resolution. The wide applicability of nanomaterials in medicines emerge from the similarity in size of biomolecule moieties of metabolic processes occurring at nano levels. Optical properties of quantum dots allow their use as biomarkers subsequent to coating with a material able to bind selectively with certain biological structures like cancer cells by fluorescent absorption followed by emission of electrons known as functionalised quantum dots. Nanomaterials on combining with biomolecules develop ability to recognize sensitive diagnostic and regulated drug delivery processes with appreciably better performances and may be used as tissue substitutes. The properties produced in organic solvents make them hydrophobic and incompatible to biological molecules. At the same time, they may be converted into water soluble form and made biocompatible through different techniques like ligand exchange, encapsulation, polymer coating (with functional groups attached to the surface) providing reactive site for bio conjugation through different processes keeping limitations of the processes in view. Nanomaterials play prominent role in medicines as obviated by growing global market for them in the field expected to reach to USD 182.3 billion by 2027 at a compounded annual growth rate of 19.9% from 2021

Nanomaterials due to their size (ranging from 0.1-100 nm, at least in one dimension) and higher ratio of surface area to volume display dominant quantum effects causing drastic changes in their chemical reactivity as well as optical, elastic, electrical and magnetic properties. The electrons due to their wave nature move very easily without scattering in nanomaterials and allow their use as biological sensors. Nano wires, semiconducting in nature, act as a versatile optoelectronic component in photodetectors sensitive to polarization and arrays with sub wavelength resolution. The wide applicability of nanomaterials in medicines emerge from the similarity in size of biomolecule moieties of metabolic processes occurring at nano levels. Optical properties of quantum dots allow their use as biomarkers subsequent to coating with a material able to bind selectively with certain biological structures like cancer cells by fluorescent absorption followed by emission of electrons known as functionalised quantum dots. Nanomaterials on combining with biomolecules develop ability to recognize sensitive diagnostic and regulated drug delivery processes with appreciably better performances and may be used as tissue substitutes. The properties produced in organic solvents make them hydrophobic and incompatible to biological molecules. At the same time, they may be converted into water soluble form and made biocompatible through different techniques like ligand exchange, encapsulation, polymer coating (with functional groups attached to the surface) providing reactive site for bio conjugation through different processes keeping limitations of the processes in view. Nanomaterials play prominent role in medicines as obviated by growing global market for them in the field expected to reach to USD 182.3 billion by 2027 at a compounded annual growth rate of 19.9% from 2021.

Quantum dots (QDs) are a group of semiconducting nanomaterials with unique optical and electronic properties. They have distinct advantages over traditional fluorescent organic dyes in chemical and biological studies in terms of tunable emission spectra, signal brightness, photostability, and so forth. Currently, the major type of QDs is the heavy metal-containing II-IV, IV-VI, or III-V QDs. Silicon QDs and conjugated polymer dots have also been developed in order to lower the potential toxicity of the fluorescent probes for biological applications. Aqueous solubility is the common problem for all types of QDs when they are employed in the biological researches, such asin vitroandin vivoimaging. To circumvent this problem, ligand exchange and polymer coating are proven to be effective, besides synthesizing QDs in aqueous solutions directly. However, toxicity is another big concern especially forin vivostudies. Ligand protection and core/shell structure can partly solve this problem. With the rapid development of QDs research, new elements and new morphologies have been introduced to this area to fabricate more safe and efficient QDs for biological applications.

Phototherapies including photothermal therapy (PTT) and photodynamic therapy (PDT) have emerged as one of the avant-garde strategies for cancer treatment. Photoacoustic (PA) imaging is a new hybrid imaging modality that shows great promise for real-time in vivo monitoring of biological processes with deep tissue penetration and high spatial resolution. To enhance therapeutic efficacy, reduce side effects and minimize the probability of over-medication, it is necessary to use imaging and diagnostic methods to identify the ideal therapeutic window and track the therapeutic outcome. With this regard, nanotheranostics with the ability to conduct PA imaging and PTT/PDT are emerging. This review summarizes the recent progress of organic nanomaterials including nearinfrared (NIR) dyes and semiconducting polymer nanoparticles (SPNs) in PA imaging guided cancer phototherapy, and also addresses their present challenges and potential in clinical applications.

The production of metal-containing nanoparticles is one of the important problems of modern science related to the creation of nanomaterials. Nanocomposites based on polymer matrices and uniformly distributed nanoparticles (quantum dots) isolated from each other in them have unique photoluminescent properties; in addition, polymer matrices are convenient stabilizers of nanoparticle growth and have good mechanical properties. Of the nanoparticles of semiconducting materials, metal chalcogenides (CdS, Cu) are of the greatest interest. In the chemical synthesis of metal sulfides in a polymer medium, H2S or a compound containing active sulfur can act as a sulfiding agent. Samples of nanocomposites based on semiconductor sulfides and polyethylene have been synthesized. The composition, structure and structure of nanoparticles were studied by X-ray phase analysis and spectroscopy. Investigated from thermophysical properties. From studies of the temperature dependence of the heat capacity of the compositions, LDPE and CdS compositions, It can be seen that there is a peak on the curve in the temperature range of 100-2250K, which almost degenerates with an increase in the concentration of the filler. Measurements of the temperature dependence of thermal conductivity and heat capacity revealed the presence of reversible structural rearrangements in polymer composites with metal oxide fillers. Moreover, various methods, within the limits of errors, fix a constant transition temperature of electrical conductivity, thermal conductivity and heat capacity, which speaks in favor of the fact that the basis of all detected anomalies is a single mechanism, i.e. structural rearrangement of defect states of polymer composites.

Novelty and creativity make life more beautiful and enjoyable! As a result, the International Symposium on Novel Materials and their Synthesis (NMS) was initiated in 2005 [1]. This is the 3rd serial symposium (NMS-III) together with the 17th International Symposium on Fine Chemistry and Functional Polymers (FCFP-XVII), which was organized by Fudan University in Shanghai 17-21 October 2007. The National Natural Science Foundation of China, Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, Shanghai Society of Chemistry and Chemical Industry,and the National Basic Research Program of China (2007CB209700) provided valuable financial support.The symposium was carried out under the auspices of IUPAC.The main objectives of the symposium were to present state-of-the-art preparation of novel materials, and to discuss their performance and application potentials. The wide scope of the symposium provided a valuable multidisciplinary academic exchange on new ideas and the latest findings for the scientific community. At the same time, the forum gave young scientists the opportunity to meet with the international authorities in their specialized areas and to quickly increase their knowledge. The symposium also opened other doors for the participants to learn something more about Fudan University, Shanghai, and China.The symposium was joined by 212 overseas participants from 34 countries and areas and some local distinguished delegates. The scientific program comprised 206 lectures and 90 posters, including one plenary lecture and one public lecture delivered by Prof. J. M. Lehn from France, the 1987 Nobel laureate in chemistry. Detailed, active, and lively discussions were covered by the following five themes:- innovative catalytic and other synthetic methods, including chiral and asymmetrical synthesis- innovative polymer materials, including supramolecular (supermolecular, dynamers), conducting, semiconducting, optoelecronic, and biobased polymers, their properties, and characteristics- innovative energy materials, including fuel cells, solar cells, lithium batteries, Ni-MH batteries, and supercapacitors- innovative nanomaterials and their preparation, characteristics, and applications- other novel materials, including drugs, perfumes, agricultural chemicals, electrical materials, photosensitive materials, displaying materials, and fine ceramics and their preparationThe program emphasized that novel materials and their preparation are dynamic research areas that are attracting growing interest from researchers, engineers, industries, and policy-makers. Furthermore, novel materials continue to find applications that serve the needs and interests of producers and consumers. Among these, energy and nanotechnologies are two urgent and important themes. A selection of 23 papers based on specially invited presentations to NMS-III/FCFP-XVII is published in this issue to demonstrate the quality and scope of the two themes of this symposium.During the symposium, the role and contributions of this academic platform to novel materialsand their synthesis are well realized by the participants and sponsors. Holding this symposium inOctober of every odd year in Shanghai is strongly recommended by the advisory board and adopted bythe organization committee.Yuping WuConference editor1. Y. P. Wu. Pure Appl. Chem.78, iii (2006).

In light of the global financial crisis, innovation becomes more critical, especially for industry. The crisis thus heightens the relevance and importance of the 5th International Symposium on Novel Materials and Their Synthesis (NMS-V) and the 19th International Symposium on Fine Chemistry and Functional Polymers (FCFP-XIX) (www.nms-iupac.org). Since the initial conference in 2005 [1], this is the 5th serial symposium of NMS together with FCFP, which was organized by Fudan University and the University of Wollongong in Shanghai, 18-22 October 2009. The National Natural Science Foundation of China, the Science and Technology Commission of Shanghai Municipality, Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, Shanghai Society of Chemistry and Chemical Industry, and the National Basic Research Program of China (2007CB209700) provided valuable financial support. The symposium was carried out under the auspices of IUPAC.The main objectives of the symposium were to present state-of-the-art preparation of novel materials, and to discuss their performance and application potentials. The wide scope of the symposium provided a multidisciplinary high-level academic exchange chance on new ideas and latest findings for the scientific community. At the same time, the forum gave young scientists the opportunity to know some international authorities in their specialized areas and to develop professionally as quickly as possible. The symposium also opened other doors for the participants to learn more about Fudan University, Shanghai, and China.The symposium was attended by 420 participants from 33 countries and areas. The scientific program comprised 7 plenary lectures, 235 invited lectures, 107 posters, and 1 NMS Nobel Public Lecture. Detailed, active, and lively discussions were covered by the following six themes:- innovative catalytic and other synthetic methods, including chiral and asymmetrical synthesis- innovative polymer materials, including supramolecular (supermolecular, dynamers), conducting, semiconducting, and biobased polymers, their properties, and characteristics- innovative energy systems, including fuel cells, solar cells, lithium batteries, and supercapacitors, and their key materials (PS-III: International)- innovative nanomaterials and their characterization and application- new ceramic materials, such as superconductors, electronic, diaelectronic, ferroelectric, piezoelectric, optoelectric, and magnetic materials- other novel materials, including drugs, perfumes, agricultural chemicals, electrical materials, photo sensitive materials, displaying materials, and fine ceramics and their preparationA selection of 17 papers based on specially invited presentations to NMS-5/FCFP-19 is published in this issue to demonstrate the quality and scope of the themes of this symposium.During the symposium, the role and contributions of this high-level academic platform to novel materials and their synthesis are well realized by the participants, sponsors, and exhibitors. In addition, the organization committee established the "Distinguished Award 2009 for Novel Materials and their Synthesis", and Prof. Makoto Shimizu from Japan and Dr. Klaus Kurz from Germany received the award for their excellent work. Three winners for the IUPAC Poster Prize were also awarded.The advisory board and the organization committee have approved holding this symposium every October. The committees also discussed the IUPAC Prof. Jiang Novel Materials Youth Prize, which will be formally awarded at the 2011 symposium with the support of IUPAC and Prof. Yingyan Jiang, the honorary chairman of this serial symposium.Yuping Wu and Guoxiu WangConference Editors1. Y. P. Wu. Pure Appl. Chem.78, iii (2006).

<div>Innovation is the impetus for the sustainable development of humanity and for better enjoyment of life, and thus the International Symposium on Novel Materials and their Synthesis (NMS) was initiated in 2005 [1]. This is the 4th serial symposium (NMS-IV) together with the 18th International Symposium on Fine Chemistry and Functional Polymers (FCFP-XVIII), which was organized by Jiangsu University in Zhenjiang 15-18 October 2008. The symposium is important especially given that it was held under the shadow of a serious subprime lending crisis and the emergence of a global economic crisis. The National Natural Science Foundation of China, Jiangsu Province Chemistry and Chemical Engineering Society, Zhenjiang City, and Yancheng Institute of Technology provided valuable financial support. The symposium was carried out under the auspices of IUPAC.<br /><br />The main objectives of the symposium were to present state-of-the-art preparation of novel materials and to discuss their performance and application potentials. The wide scope of the symposium provided a valuable multidisciplinary academic exchange of new ideas and the latest findings for the scientific community. At the same time, the forum gave young scientists the opportunity to meet with international authorities in their specialties. The symposium also allowed participants to learn more about Jiangsu University, Zhenjiang, and China.<br /><br />The symposium was attended by 209 participants from 23 countries and areas. The scientific program comprised 88 lectures and 95 posters. Detailed, active, and lively discussions were covered by the following five themes:<br /><br />- innovative catalytic and other synthetic methods, including chiral and asymmetrical synthesis<br />- innovative polymer materials, including supramolecular (supermolecular, dynamers), conducting, semiconducting, optoelecronic and biobased polymers, their properties and characteristics<br />- innovative energy materials, including fuel cells, solar cells, lithium batteries, Ni-MH batteries, and supercapacitors<br />- innovative nanomaterials and their preparation, characteristics, and applications<br />- other novel materials, including drugs, perfumes, agricultural chemicals, electrical materials, photosensitive materials, displaying materials, and fine ceramics, and their preparation<br /><br />The program served to emphasize that novel materials and their preparation are dynamic research areas that are attracting growing interest from researchers, engineers, industries, and policy-makers. Furthermore, novel materials continue to find applications that serve the needs and interests of producers and consumers. A selection of 13 papers based on invited presentations to NMS-4/FCFP-18 is published in this issue to demonstrate the quality and scope of the themes of this symposium.<br /><br />During the symposium, the role and contributions of this academic platform to novel materials and their synthesis are well realized by the participants and sponsors. The regular on-going schedule of this symposium in October is strongly recommended by the advisory board and adopted by the organization committee.<br /><br /><i>Yuping Wu and Jimin Xie</i><br />Conference Editors<br /><br />1. Y. P. Wu. <i>Pure Appl. Chem.<i> <b>78</b> (10), iii-iv (2006).<br /></div>

Quartzite sculptures are considered some of the most impressive and informative archaeological remains which have been found in the most of Egyptian archaeological sites. Regrettably, quartzite sculptures suffer from many deterioration aspects such as granular disintegration, scaling, cracking, efflorescence, soiling, microbiological colonization. Water is the main aggressive deterioration factor of stones and stone-based monuments, as in addition to its direct role in deterioration mechanisms, it plays as a catalyst in the physicochemical and microbiological deterioration processes.During the last two decades, polymer nanocomposites have widely been applied in the field of cultural heritage conservation due to their unique physical and chemical characteristics. Zinc oxide nanoparticles are among the most important semiconductive nanomaterials that have been applied in the fabrication of nanocomposites. They have been demonstrated to improve the physicochemical and mechanical properties of polymers. In addition, zinc oxide nanoparticles were mixed with polymers in order to fabricate superhydrophobic and self-cleaning protective materials.The aim of this paper is to evaluate the efficiency of zinc oxide nanocomposites, in order to select the best of them for the consolidation and protection of a colossal quartzite statue of Ramesses II. The properties of the treated quartzite samples were comparatively examined by colourimetric measurements, static water contact angle, compressive strength, and scanning electron microscope.

This thesis is concerned with the influence of nanoscale boundaries and interfaces upon the electronic processes that occur within both organic and inorganic semiconductors. Photoluminescent polymers, highly conducting polymers and nanoscale inorganic semiconductors have been investigated using state-of-the-art ultrafast optical techniques, to provide information on the sub-picosecond photoexcitation dynamics in these systems. The influence of dimensionality on the excitation transfer dynamics in a conjugated polymer blend is studied. Using time-resolved photoluminescence spectroscopy, the transfer transients both for a three-dimensional blend film, and for quasi-two-dimensional monolayers formed through intercalation of the polymer blend between the crystal planes of a SnS2 matrix have been measured. A comparison of the experimental data with a simple, dimensionality-dependent model is presented, based on point dipole electronic coupling between electronic transition moments. Within this approximation, the energy transfer dynamics are found to adopt a three-dimensional character in the solid film, and a two-dimensional nature in the monolayers present in the SnS2 -polymer nanocomposite. The time-resolved conductivity of isolated GaAs nanowires has been investigated by optical-pump terahertz-probe time-domain spectroscopy. The electronic response exhibits a pronounced surface plasmon mode that forms within 300 fs, before decaying within 10 ps as a result of charge trapping at the nanowire surface. The mobility has been extracted using the Drude model for a plasmon and is found to be remarkably high, being roughly one third of that typical for bulk GaAs at room-temperature and indicating the high quality and low bulk defect density in the nanowires studied. Finally, the time-resolved conductivity dynamics of photoexcited polymer-fullerene bulk heterojunction blends for two model polymers, P3HT and MDMO-PPV, blended with PCBM are presented. The observed terahertz-frequency conductivity is characteristic of dispersive charge transport for photoexcitation both at the π−π* absorption peak (560 nm for P3HT), and significantly below it (800 nm). The photoconductivity at 800 nm is unexpectedly high, which is attributed to the presence of a charge transfer complex. In addition, the excitation-fluence dependence of the photoconductivity is studied over more than four orders of magnitude. The time-averaged photoconductivity of the P3HT:PCBM blend is over 20 times larger than that of P3HT, indicating that long-lived positive polarons are responsible for the high photovoltaic efficiency of polymer:fullerene blends. At early times (~ ps) the linear dependence of photoconductivity upon fluence indicates that interfacial charge transfer dominates as an exciton decay pathway, generating charges with mobility of at least ~0.1cm2 V−1 s−1. At later times, a sub-linear relationship shows that carrier-carrier recombination effects influence the conductivity on a longer timescale (> 1 μs).

Recent advances in the study of the synthesis, structure and applications of 1-D composites containing conducting polymers are discussed in this review. Conducting composites can form 1-D structures with metal and metal oxides, 1-D carbon nanomaterials, semiconducting materials, crystals of metalloorganic complexes. Advanced synthetic approaches allow for the formation of well-organized structures with polymeric phase deposited both on the surface of 1-D material and inside of the 1-D tubes. 1-D polymeric wires can also serve as a matrix for the formation 1-D composites with other materials. 1-D nanocomposites containing conducting polymers exhibit many exceptional properties which allow for various practical applications including energy converting and energy storage devices, electronic nanodevices, chemical, electrochemical and biochemical sensors, catalysis and electrocatalysis.

Currently, in the field of biomedical engineering and biological applications, the use of soft florescent nanomaterials has increased because of their excellent biocompatibility, easy biofunctionalization, and high brightness properties. This chapter summarizes the current developments of nano-sized fluorescent soft biological imaging agents. Many fluorescent soft nanoparticles like biomaterial-based NPs, vesicles, micelles, nanogels, small-molecule organic NPs, semiconducting polymer NPs, and dye-doped polymer NPs are mentioned briefly starting from the preparation methods, their structures, their optical properties, as well as their functionalization. Depending upon the nano-sized imaging agents' functional as well as optical properties, their uses are briefly described in relation to Vivo imaging, cellular process imaging, and in vitro imaging by using nonspecific and specific targeting.

Stretchable and wearable strain-sensing devices are appropriate for motion detection, biomedical monitoring, human-machine interaction. These pressure sensors are working based on numerous electrophysical phenomena's such as piezoelectric, capacitive and piezoresistive reactions towards mechanical stretching. Piezoresistive sensors are highly favored due to their features like high sensitivity, fast response, easy fabrication and low energy requirement. They are generally fabricated using a suitable polymeric matrix and electrically conductive fillers, such as graphite, graphene or carbon nanotubes. MXenes are a relatively new family of (2D) transition metal carbides, nitrides or carbonitrides, produced by the selective chemical etching of “A” from MAXphases, where M is a transition metal, A is a group IIIA or IVA element and X is C or N. These nanomaterials are first reported in 2011 by the Gogotsi and Barsoum groups. These materials have received tremendous attention from the scientific community due to their excellent physiochemical properties, electrical conductivity and hydrophilicity. Herein, we report the preparation, characterization and piezoresistive individualities of semiconductive, electrospun mats composed of copolyamide 6, 10 and Ti3C2Tx. We observed that the relative resistance of the sensor increased with an increase in the Ti3C2Tx content, and the materials with higher electrical conductivity showcased a significantly higher sensitivity to applied pressure until reaching the percolation limit (font size can be increased).