scholarly journals Toxicity Risks of Nanomaterials used in the Building Construction Materials

2020 ◽  
Vol 01 ◽  
Author(s):  
Nakshatra Bahadur Singh ◽  
Muhammad Bilal ◽  
Mehmet Serkan Kırgız ◽  
Tuan Anh Nguyen ◽  
Susai Rajendran ◽  
...  
Keyword(s):  
Carbon Nanomaterials ◽  
High Surface ◽  
High Surface Area ◽  
Construction Materials ◽  
Physicochemical Characteristics ◽  
Building Construction ◽  
Environmental Matrices ◽  
Nanoscale Structures ◽  
Advantages And Disadvantages ◽  
Metal Oxide Nanostructures

Introduction: In recent years, there has been a growing research interest on the applications of a range of nanostructured materials in construction materials (i.e. asphalt concrete, bricks, concrete, timber, steel, and mortar), manufacturing, electronics, cosmetics, and medicine. The use of nanoscale structures in the construction industry offers exceptional physicochemical characteristics for the modification of construction materials. Nanomaterials, which are being used in cement and concretes, are carbon nanomaterials (Graphene, CNTs, CNFs), nanosilica, nano Al2O3, nanometakaoline, nano Ca- CO3, nano Fe2O3, nanoTiO2. Methods: These materials improve the properties of concretes by modifying the microstructure and also improve the mechanical properties. The improvement in mechanical and durability properties of concretes in the presence of nanoparticles are due to their smaller size (<100 nm), high surface area, and energy. Results: Nevertheless, all these nanoscale particles find their way (either directly or indirectly) to various environmental matrices such as groundwater, surface water, rivers, seas, lakes, and soil. The potential bioaccumulation of metal oxide nanostructures results in undesirable effects on animals, aquatic biota, plants, and humans. Therefore, it has become crucial to determine toxicity levels during the use of these multifunctional nanoscale materials. Conclusion: This study presents an overview of the advantages and disadvantages of nanomaterials in concretes and related materials. A particular emphasis has been given to discuss the potential toxicity risks of nanomaterials used in building construction materials.

scholarly journals Application of Nanostructured Carbon-Based Electrochemical (Bio)Sensors for Screening of Emerging Pharmaceutical Pollutants in Waters and Aquatic Species: A Review

Nanomaterials ◽  
2020 ◽  
Vol 10 (7) ◽  
pp. 1268 ◽  
Author(s):  
Álvaro Torrinha ◽  
Thiago M. B. F. Oliveira ◽  
Francisco W.P. Ribeiro ◽  
Adriana N. Correia ◽  
Pedro Lima-Neto ◽  
...  
Keyword(s):  
Carbon Nanomaterials ◽  
Low Cost ◽  
High Surface ◽  
High Surface Area ◽  
Aquatic Species ◽  
Transfer Rates ◽  
Production Methods ◽  
Pharmaceutical Pollutants ◽  
Carbon Based Nanomaterials ◽  
Carbon Based

Pharmaceuticals, as a contaminant of emergent concern, are being released uncontrollably into the environment potentially causing hazardous effects to aquatic ecosystems and consequently to human health. In the absence of well-established monitoring programs, one can only imagine the full extent of this problem and so there is an urgent need for the development of extremely sensitive, portable, and low-cost devices to perform analysis. Carbon-based nanomaterials are the most used nanostructures in (bio)sensors construction attributed to their facile and well-characterized production methods, commercial availability, reduced cost, high chemical stability, and low toxicity. However, most importantly, their relatively good conductivity enabling appropriate electron transfer rates—as well as their high surface area yielding attachment and extraordinary loading capacity for biomolecules—have been relevant and desirable features, justifying the key role that they have been playing, and will continue to play, in electrochemical (bio)sensor development. The present review outlines the contribution of carbon nanomaterials (carbon nanotubes, graphene, fullerene, carbon nanofibers, carbon black, carbon nanopowder, biochar nanoparticles, and graphite oxide), used alone or combined with other (nano)materials, to the field of environmental (bio)sensing, and more specifically, to pharmaceutical pollutants analysis in waters and aquatic species. The main trends of this field of research are also addressed.

scholarly journals Carbon nanomaterials for metal-free electrocatalysis

2020 ◽  
Vol 3 (1) ◽  
pp. 55
Author(s):  
Ana M.B. Honorato ◽  
Mohd Khalid
Keyword(s):  
Energy Conversion ◽  
Carbon Nanomaterials ◽  
Low Cost ◽  
High Surface ◽  
High Surface Area ◽  
Metal Free ◽  
Hydrogen Evolution Reactions ◽  
Storage Technologies ◽  
Conversion Technologies ◽  
Carbon Based

Carbon materials are continuing in progress to accomplish the requirements of energy conversion and energy storage technologies because of their plenty in nature, high surface area, outstanding electrical properties, and readily obtained from varieties of chemical and natural sources. Recently, carbon-based electrocatalysts have been developed in the quest to replacement of noble metal based catalysts for low cost energy conversion technologies, such as fuel cell, water splitting, and metal-air batteries. Herein, we will present our short overview on recently developed carbon-based electrocatalysts for energy conversion reactions such as oxygen reduction, oxygen evolution, and hydrogen evolution reactions, along with challenges and perspectives in the emerging field of metal-free electrocatalysts.

scholarly journals Carbon Nanomaterials for the Treatment of Heavy Metal-Contaminated Water and Environmental Remediation

2019 ◽  
Vol 14 (1) ◽  
Author(s):  
Rabia Baby ◽  
Bullo Saifullah ◽  
Mohd Zobir Hussein
Keyword(s):  
Heavy Metal ◽  
Surface Area ◽  
Environmental Remediation ◽  
Carbon Nanomaterials ◽  
Heavy Metal Contamination ◽  
High Surface ◽  
High Surface Area ◽  
Contaminated Water ◽  
Removal Of Heavy Metals ◽  
Carbon Based Nanomaterials

Abstract Nanotechnology is an advanced field of science having the ability to solve the variety of environmental challenges by controlling the size and shape of the materials at a nanoscale. Carbon nanomaterials are unique because of their nontoxic nature, high surface area, easier biodegradation, and particularly useful environmental remediation. Heavy metal contamination in water is a major problem and poses a great risk to human health. Carbon nanomaterials are getting more and more attention due to their superior physicochemical properties that can be exploited for advanced treatment of heavy metal-contaminated water. Carbon nanomaterials namely carbon nanotubes, fullerenes, graphene, graphene oxide, and activated carbon have great potential for removal of heavy metals from water because of their large surface area, nanoscale size, and availability of different functionalities and they are easier to be chemically modified and recycled. In this article, we have reviewed the recent advancements in the applications of these carbon nanomaterials in the treatment of heavy metal-contaminated water and have also highlighted their application in environmental remediation. Toxicological aspects of carbon-based nanomaterials have also been discussed.

Insight into municipal solid waste fly ash (MSWFA) heavy metals speciation by selective extractions and geochemical modelling

2021 ◽  
Author(s):  
Davide Bernasconi ◽  
Caterina Caviglia ◽  
Enrico Destefanis ◽  
Linda Pastero ◽  
Costanza Bonadiman ◽  
...  
Keyword(s):  
Heavy Metals ◽  
Fly Ash ◽  
Municipal Solid Waste ◽  
Solid Waste ◽  
High Surface ◽  
High Surface Area ◽  
Construction Materials ◽  
Analytical Techniques ◽  
Geochemical Modelling ◽  
Insight Into

&lt;p&gt;Nowadays municipal solid waste incineration (MSWI) has become a widespread and consolidated technology for MSW treatment all over the world. Indeed, it allows to reach up to 90% of waste volume reduction, while also producing energy. However, the incineration process has some drawbacks, one of which is the production of different residues that must be disposed of. Specifically, particular attention must be paid to fly ash (FA), which generally represents one of the most dangerous residues. FA is collected by the flue gas purification system and counts for around the 5% w/w of total incinerated waste. MSWI FA is regulated as a hazardous waste, mainly due to high concentrations of heavy metals (Pb, Cr, Zn, Cd) and soluble salts (chlorides and sulfates). Moreover, the average size of FA particles can be as low as 50-20 &amp;#181;m, thus determining a high surface area, which can increase toxic elements release into the environment. Therefore, many preliminary physicochemical stabilization treatments have been proposed over the years for their possible reuse as construction materials (e.g. water washing, thermal treatment, etc..). However, a detailed characterization of the residue in terms of heavy metals speciation is often overlooked. Indeed, this represents necessary information in order to understand and control the residue behavior in a reuse scenario and to design stabilization treatments as effective as possible.&lt;/p&gt;&lt;p&gt;In this work the analysis of heavy metals distribution and speciation of Turin MSW FA has been conducted, by combining both experimental treatments and geochemical modelling. In particular, a 4-step sequential extraction method has allowed to evaluate how heavy metals are distributed among four fractions with different physicochemical properties and, then, to deduct preliminary considerations about their leaching availability. In addition, pH-dependant leaching tests coupled by geochemical modelling using Virtual MINTEQ software has provided a more detailed insight into heavy metals speciation, by proposing possible phases which are often not detected by bulk analytical techniques. Finally, a general assessment of the hazardousness of Turin FA is discussed.&lt;/p&gt;

Magnetite hybrid photocatalysis: advance environmental remediation

2016 ◽  
Vol 36 (3) ◽  
Author(s):  
Samira Bagheri ◽  
Nurhidayatullaili Muhd Julkapli
Keyword(s):  
Environmental Remediation ◽  
Suspended Solids ◽  
High Surface ◽  
High Surface Area ◽  
Oxidative Degradation ◽  
Suspended Material ◽  
Separation Processes ◽  
Magnetic Photocatalyst ◽  
Research Attention ◽  
Advantages And Disadvantages

AbstractOne of the main public concerns is the aquatic habitat and its corresponding issues because of the incessant contamination of the ecological water systems. In recent years, research attention has been focused on processes that lead to an improved oxidative degradation of organic pollutants. Therefore, semiconductor photocatalysis technology has aroused scientists’ interest in environmental remediation. Although several semiconductors have proven to be ideal candidates for the treatment of water pollution, the efficient separation and recycling of this fine-powdered photocatalyst is still a scientific problem when applied in practice, including separation process, selectivity, and dispersion. A photocatalyst with magnetic properties allows the use of the technique of magnetic separation, which is one of the most effective and simple methods for removing suspended solids from wastewater without the need for further separation processes. The magnetic photocatalyst allows its use as a suspended material, providing the advantage to have a high surface area for reaction. This review highlights the advantages and disadvantages of current photocatalyst systems. Moreover, it focuses on hybrid magnetic photocatalysts, including metals and nonmetals, metal oxides, carbon-based materials, and ceramics.

scholarly journals Electrospinning of Nanofibers and Their Applications for Energy Devices

2015 ◽  
Vol 2015 ◽  
pp. 1-20 ◽  
Author(s):  
Xiaomin Shi ◽  
Weiping Zhou ◽  
Delong Ma ◽  
Qian Ma ◽  
Denzel Bridges ◽  
...  
Keyword(s):  
Energy Harvesting ◽  
Fossil Fuels ◽  
High Surface ◽  
High Surface Area ◽  
Lithium Ion ◽  
Hydrogen Energy ◽  
Energy Devices ◽  
Advantages And Disadvantages ◽  
Energy Technologies ◽  
And Storage

With the depletion of fossil fuels and the increasing demand of energy for economic development, it is urgent to develop renewable energy technologies to sustain the economic growth. Electrospinning is a versatile and efficient fabrication method for one-dimensional (1D) nanostructured fibers of metals, metal oxides, hydrocarbons, composites, and so forth. The resulting nanofibers (NFs) with controllable diameters ranging from nanometer to micrometer scale possess unique properties such as a high surface-area-to-volume and aspect ratio, low density, and high pore volume. These properties make 1D nanomaterials more advantageous than conventional materials in energy harvesting, conversion, and storage devices. In this review, the key parameters for e-spinning are discussed and the properties of electrospun NFs and applications in solar cells, fuel cells, nanogenerators, hydrogen energy harvesting and storage, lithium-ion batteries, and supercapacitors are reviewed. The advantages and disadvantages of electrospinning and an outlook on the possible future directions are also discussed.

scholarly journals UiO66–NH2 AS A NEW PHOTOCATALYST FOR THE DEGRADATION OF p–XYLENE IN GASEOUS PHASE

2018 ◽  
Vol 55 (1B) ◽  
pp. 40
Author(s):  
Loc L. C.
Keyword(s):  
Thin Film ◽  
Diffuse Reflectance Spectroscopy ◽  
Light Emitting Diode ◽  
Atmospheric Oxygen ◽  
High Surface ◽  
High Surface Area ◽  
Reaction System ◽  
Physicochemical Characteristics ◽  
Dip Coating ◽  
Total Power

Ammonia functionalized UiO66 (UiO66–NH2) in the form of thin film was synthesized by a solvothermal method combined with a dip–coating technique and determined with physicochemical characteristics by X–ray diffraction (XRD), scanning electron microscopy (SEM), nitrogen physisorption measurements (BET), infrared spectroscopy (IR), thermogravimetric analysis (TGA), and ultraviolet–visible diffuse reflectance spectroscopy (UV–Vis DRS). Also, the obtained material was assessed on the photoactivity in the degradation of p–xylene in the gas phase. Photoreaction was carried out in the micro flow reaction system with the radiation sources of a UV lamp (λ = 365 nm, the power of 8 W) and 81 pieces of light emitting diode (LED) (λ = 400–510 nm, total power of 19.2 W). The results showed that UiO66–NH2 was successfully prepared in the ball shape and featured by a high surface area of up to 576 m2/g, a band gap energy of 2.83 eV and a thermal stability of up to 673 K. Additionally, UiO66–NH2 thin film catalyst performed an efficiency of 1.27 g/gcat in the earlier 60 minutes of the photodegradation of p–xylene. The optimal treatment conditions were established with the moisture content of 8.65 mg/L and the atmospheric oxygen with the concentration of 300 mg/L.

scholarly journals Carbon nanomaterials: synthesis and applications to development of electrochemical sensors in determination of drugs and compounds of clinical interest

2020 ◽  
Vol 38 (3) ◽  
Author(s):  
Laís S. Porto ◽  
Daniela N. Silva ◽  
Ana Elisa F. de Oliveira ◽  
Arnaldo C. Pereira ◽  
Keyller B. Borges
Keyword(s):  
Carbon Nanomaterials ◽  
Electrochemical Sensors ◽  
Biological Fluids ◽  
Low Cost ◽  
High Surface ◽  
High Surface Area ◽  
Synthesis Methods ◽  
Electrocatalytic Effect ◽  
Clinical Interest

AbstractIt is notorious that researches related to electrochemical sensors increased significantly due the promising characteristics that these devices present such as the possibility of obtaining information, with minimum manipulation of the studied system, in real time, and with low environmental impact. This article covers the carbon nanomaterials, presenting important aspects such as main properties, synthesis methods, and the application of these materials in the development of electrochemical sensors for the analysis of drugs and compounds of clinical interest. In this context, drug analysis is extremely important for quality control, to ensure that the medicine fulfills its role effectively without possible complications that could compromise the patient’s health and quality of life. In addition, analytical methods capable of determining compounds of clinical interest in biological fluids are extremely important for the indication of effective diagnoses. Thus, the versatility, selectivity, and portability of the electroanalytical techniques make the electrochemical sensors a favorite tool for the determination of drugs and compounds of clinical interest. It will be possible to follow in the present work that carbon nanomaterials have excellent thermal and electrical conductivity, strong adsorption capacity, high electrocatalytic effect, high biocompatibility, and high surface area. The possibility of formation of different composite materials based on carbonaceous nanomaterials that makes these materials promising for the development of analytical sensors, contributing to rapid, sensitive, and low-cost analyses can also be highlighted.

scholarly journals Nanoemulsions: Factory for Food, Pharmaceutical and Cosmetics

Processes ◽  
2019 ◽  
Vol 7 (9) ◽  
pp. 617 ◽  
Author(s):  
Nor Azrini Nadiha Azmi ◽  
Amal A. M. Elgharbawy ◽  
Shiva Rezaei Motlagh ◽  
Nurhusna Samsudin ◽  
Hamzah Mohd. Salleh
Keyword(s):  
Phase Inversion ◽  
High Surface ◽  
High Surface Area ◽  
High Energy ◽  
Review Article ◽  
Low Energy ◽  
Energy Methods ◽  
High Pressure Homogenization ◽  
Spontaneous Emulsification ◽  
Advantages And Disadvantages

Nanotechnology, particularly nanoemulsions (NEs), have gained increasing interest from researchers throughout the years. The small-sized droplet with a high surface area makes NEs important in many industries. In this review article, the components, properties, formation, and applications are summarized. The advantages and disadvantages are also described in this article. The formation of the nanosized emulsion can be divided into two types: high and low energy methods. In high energy methods, high-pressure homogenization, microfluidization, and ultrasonic emulsification are described thoroughly. Spontaneous emulsification, phase inversion temperature (PIT), phase inversion composition (PIC), and the less known D-phase emulsification (DPE) methods are emphasized in low energy methods. The applications of NEs are described in three main areas which are food, cosmetics, and drug delivery.

scholarly journals Carbon Nanomaterials in Silica Aerogel Matrices

2010 ◽  
Vol 1258 ◽  
Author(s):  
Christopher E. Hamilton ◽  
Manuel E Chavez ◽  
Juan G. Duque ◽  
Gautam Gupta ◽  
Stephen Doorn ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Carbon Nanomaterials ◽  
High Surface ◽  
High Surface Area ◽  
Supercritical Drying ◽  
Silica Gels ◽  
Low Density ◽  
Wide Range ◽  
High Surface Area Materials ◽  
Walled Carbon Nanotubes

AbstractSilica aerogels are ultra low-density, high surface area materials that are extremely good thermal insulators and have numerous technical applications. However, their mechanical properties are not ideal, as they are brittle and prone to shattering. Conversely, single-walled carbon nanotubes (SWNTs) and graphene-based materials, such as graphene oxide, have extremely high tensile strength and possess novel electronic properties. By introducing SWNTs or graphene-based materials into aerogel matrices, it is possible to produce composites with the desirable properties of both constituents. We have successfully dispersed SWNTs and graphene-based materials into silica gels. Subsequent supercritical drying results in monolithic low-density composites having improved mechanical properties. These nanocomposite aerogels have great potential for use in a wide range of applications.

Sign in / Sign up

Export Citation Format

Share Document