A Mini-Review on Nanostructured g-C3N4 Photocatalysts for Solar Fuel Production

Graphitic carbon nitride (g-C3N4) is an important photocatalytic material that receives a lot of research attention globally. This is because of its favourable thermal and chemical stability as well as electronic band structure. However, the photocatalytic performance of the bulk g-C3N4 is limited by fast recombination of electron-hole pair and poor visible light-harvesting ability. Thus, different strategies, such as heterostructuring, nanotuning, doping, etc., have been adopted to overcome the aforementioned challenges to enhance the photocatalytic performance of g-C3N4. In recent times, various nanostructured g-C3N4 photocatalytic materials with various tuned morphologies have been designed and fabricated in literature for different photocatalytic activities. This mini-review summarized the progress development of nanostructured g-C3N4 photocatalysts with various tuned morphologies for solar fuel generation. The article briefly highlights the research status of various g-C3N4 with tuned morphologies and enhanced solar fuel generation abilities. Finally, a conclusion and future research were also suggested, opening up new areas on g-C3N4 photocatalysis.

Multiwall carbon nanotubes: A review on synthesis and applications

: MWCNTs are elongated cylindrical nanoobjects made of sp2 carbon. They have a diameter of 3–30 nm and can grow to be several centimetres long. Therefore, their aspect ratio can range between 10 to 10 million. Carbon nanotubes are the foundation of nanotechnology. It is an exceptionally fascinating material. CNTs possess excellent properties such as mechanical, electrical, thermal, high adsorption, outstanding stiffness, high strength and low density with a high aspect ratio. These properties can be useful in the fabrication of revolutionary smart nano materials. Demand for lighter and more robust nano materials in different applications of nanotechnology is increasing every day. Various synthesis techniques for the fabrication of MWCNTs, such as CVD, Arc discharge, flame synthesis, laser ablation, and spray pyrolysis, are discussed in this review article, as are their recent applications in a variety of significant fields. The first section presents a brief introduction of CNTs, then the descriptions of synthesis methods and various applications of MWCNTs in the field of energy storage and conversion, biomedical, water treatment, drug delivery, biosensors, bucky papers and resonance-based biosensors are introduced in the second section. Due to their improved electrical, mechanical, and thermal properties, MWCNTs have been extensively used in the manufacturing and deployment of flexible sensors.

Introducing nanoclay and silica-based composites as a new approach for improving chemical and mechanical properties of soil, A review

: Layered silicates (nanoclay) are new types of nanomaterials derived from clay minerals with wide range application in different fields such as catalysts, soil industry and etc. Nanoclays are wide ranges of naturally occurring inorganic minerals with different derivatives. Montmorillonite is a well-known nanoclay consisting of 2:1 layered structure with two-silica tetrahedron sandwiching an alumina octahedron. In nature, nanoclays can be found in both crystalline (phyllosilicates) and non-crystalline (imogolite) forms. . Nanoclays incorporated into polymer matrices have demonstrated a significant capability to improve the tensile and barrier properties of soil. Nanoclays play a vital role in enhancing soil quality due to its high surface area and porous structure. On the other hand, due to the positive charge of sand grains and the chemical compositions of clay particles, the negatively charged clay particles help to create a good condition to improving soil properties. According to the best of our knowledge, there is not any review paper for study the role of nanoclays on soil samples. This review paper describes the role of nanoclay compounds in the improved properties of soil samples and introduces different types of modified nanoclays used in soil samples. Reported results showed nanoclays with the complex structures are useful nanomaterials for improving the quality of soil samples.

Nanoparticle Production of Zingiber officinale Roscoe Rhizome Extracts by ESS (expansion of supercritical solution)

Aims: To propose a modified RESS method of herbal pharmaceutical extracts nanoparticle production. Background: A vast number of methods have been applied to water-insoluble pharmaceuticals to improve their solubility. Nanoparticle production of pharmaceuticals is considered as one of the high-speed ways to improve solubility. Objective: Supercritical CO2 was applied to extract Zingiber officinale Roscoe rhizome pharmaceutical. Then a modified RESS (rapid expansion of supercritical solution) method, called ESS (expansion of supercritical solution), was exerted to obtain NPs (nanoparticles) of the extracted pharmaceuticals. Methods: Initially, applying high pressure in supercritical CO2 contributed to the extract dissolution such that supercritical CO2 was saturated with the sample. Then by decreasing the pressure, an expansion occurred in the saturated medium. This expansion reduced the power of supercritical CO2 solvent and induced the sample nanoparticle nucleation in the needle valve. Conclusion: Unlike rapid expansion of supercritical solution methodology, in this technique, the initial and secondary pressures were permanently above the critical pressure to provide a gentle expansion, which contributes to the production of uniform and small particles. The obtained uniform NPs had a narrow size distribution. Consequently, ESS technique can be considered as an efficient technique for improving the solubility of hydrophobic pharmaceuticals such as [6]-gingerol.

Nanotherapeutics in Tumour Microenvironment for Cancer Therapy

Background: Cancer continues to be the most annihilating illness and despite vast research in understanding cancer biology as well as rational drug designing progressing profoundly, cancer remains the second leading cause of death worldwide. The conventional chemotherapeutic agents being exploited for cancer therapy contain several limitations, including less selectivity, nonspecific targeting and high off-target effects, and the emergence of multidrug resistance. These drawbacks can be addressed by employing the use of nanotherapeutics. Objective: The main objective of this review is to summarize various mechanisms of cancer genesis. It focuses on several strategies employed for modifying nano formulations for localization and emerging stimuli-based nanotherapeutics with recent examples. Methods: The method involved the collection of the articles from different search engines like Google, PubMed, and ScienceDirect for the literature to get appropriate information regarding the topics. Results: Studies revealed that nanoscale-based therapy provides targeted delivery, minimizes the off-target effects, and improves the therapeutic efficacy of the treatment modalities. The characteristics of nanoparticles like larger surface area become favourable and provide a platform for surface modifications, thereby improving cell targeting, internalization, and opportunities for delivering multiple agents. Advances in rational designing like stimuli-responsive therapies employing the use of sensitive nanocarriers, further provide high specificity, controlled release, and more efficient delivery of chemotherapeutic agents. Conclusion: Characteristics of the nanoscale delivery system like larger surface area provide us with ample options for desired modifications, hence providing multimodal delivery of chemotherapeutic agents in cancer treatment. Nano therapy serves well as a potential tool for improving cancer therapies.

Impact of Band-Gap Graded Intrinsic Layer on Single-Junction Band-Gap Tailored Solar Cells

Objective: The work investigates the performance of intrinsic layers with and without band-gap tailoring in single-junction amorphous silicon-based photovoltaic cells. The work proposes single-junction amorphous silicon solar cells in which band-gap grading has been done between layers as well as within each layer for the first time. Materials & Methods: The samples of hydrogenated amorphous silicon-germanium with different mole fractions are fabricated, and their band-gaps are validated through optical characterization and material characterization. A single-junction solar cell with an intrinsic layer made up of hydrogenated amorphous silicon (aSi:H) having a band-gap of 1.6 eV is replaced by continuously graded hydrogenated amorphous silicon-germanium (aSi1-xGe x :H ) intrinsic bottom layers having band-gaps ranging from 0.9 eV to 1.5 eV. The proposed structure has been considered as a variant of previously designed single-junction band-gap tailored structures. Results: The suitable utilization of band-gap tailoring on the intrinsic absorber layer aids more incident photons in energy conversion and thereby attain a better short circuit current density of 19.89 mA/cm2. Conclusion: A comparative study on performance parameters of solar cell structures with graded band-gap intrinsic layer and the ungraded single band-gap intrinsic layer has been done. The graded band-gap intrinsic layer structure results in better conversion efficiency of 15.55%, while its ungraded counterpart contributes only 14.76 %. Further, the proposed solar structure is compared with the performance parameters of recent related works. The layers used in the proposed solar structure are of amorphous-phase only, which reduces structural complexity. The use of a lesser number of active layers reduces the number of fabrication steps and manufacturing cost compared to state-of-the-art.

Green Synthesis of Silver Chloride Nanoparticles using Phlomoides labiosa (Bunge) Adylov, Kamelin&Makhm Herbal Extract by Investigating Antioxidant Properties and Antibacterial Effects

Background: Considering the high cost of nanoparticles chemical synthesis and bacteria high resistance against antibiotics, investigating silver particles biosynthesis and also their effect on clinical and standard strains of different bacteria is important. Objective: This study investigates the feasibility of green synthesis of silver chloride nanoparticles by labiosa (Bunge) Adylov, Kamelin & Makhm Phlomoides (Eremostachyslabiosa Bunge) herbal extract, and Phlomoides binaludensis Salmaki & Joharchi (Binaloud Cistanchetubulosa) plant. Methods: Scanning Electron Microscope (SEM), X-Ray Diffraction (XRD), UV-Visible Spectroscopy, and Energy-Dispersive X-ray Spectroscopy (EDS) were used for nanoparticles characterization. The antibacterial property of extracts and synthesized nanoparticles was evaluated against Staphylococcus aureus, bacillus cereus, and escherichia coli by agar disk diffusion and well diffusion, respectively. As antioxidants existing in plants are expected to act as regenerators in nanoparticles synthesis. The plants used were investigated considering the existence of antioxidant through two DPPH and FRAP methods. Total values of phenol and IC50 determined in the extract of considered plants. Results: The results showed that what has been successful in nanoparticles synthesis is silver chloride nanoparticles synthesis which is due to the existence of chlorinated compounds in the herbal extract. Synthesized nanoparticles are spherical, and they are in the 27-35 nm range size, and synthesized nanoparticles were distributed consistently. Also, nanoparticles enjoyed significant antibacterial activity. Conclusion: IC50 was 0.56 mg/ml and 0.96 mg/ml for the aerial organs of Eremostachyslabiosa Bunge and Binaloud Cistanchetubulosa, respectively, in this study, while it was 0.38 mg/ml for BHT synthetic antioxidant. Also, iron regeneration ability was reported 255.990 and 64.110 Fe ion mmol/extract gr by the extracts.

The impact of hydrogenation conditions on the physical properties of the degenerated Ni/Al co-doped diluted magnetic semiconductor anatase nanoparticles

: Anatase (TiO2) nanoparticles co-doped with Ni/Al ions were synthesized by a thermo-precipitation method. The samples were characterized by using X‐Ray diffraction and optical absorption spectroscopy. The structural/optical investigations established the development of substitutional solid solutions: TiO2:Ni:Al. The magnetization investigations were performed to study the generated stable ferromagnetic properties of the samples due to the Ni2+ doping. To boost the created ferromagnetic properties, Al ions co-dopings were employed to supply/densify the itinerant electrons. It was planned to decide the suitable hydrogenation conditions and temperature (TH), which are necessary to create appreciable strength of ferromagnetic properties in the host co-doped samples based on TiO2 for practical uses. The results established that the ferromagnetic energy (Umag) was increased by ~240% and the saturation magnetization by ~140% with increasing of TH from 400 oC to 500oC. The obtained Msat was higher by ~50 times than that previously attained for Ni-doped TiO2. Such novel results were discussed and explained through the spin-spin Heisenberg interactions.

Nanosize Carriers for Drug and Vaccine Delivery: Advances and Challenges

: Nanomedicine has emerged as a lucrative option, which attracts the attention of scientific and industrial stalwarts for its enormous potential and new business opportunities in the health sector. Since it encompasses physical, chemical, and biological interventions used for the transformation of bulk materials into nanomaterials (NMs) with particles size ~ 1-100 nm for highly specific medical applications. Therefore its effect on diagnosis, efficacy, treatment, and prevention of diseases may easily be foreseen. The credit goes to nanotechnology, which has emerged with the ability to manipulate the NMs concerning size, shape, composition as well as surface characteristics. Due to the advantages of their tiny size as well as novel properties, NMs are useful for loading more drugs with controlled release and specific targeting. Although full bloom of nanomedicine realization might take years, a recent innovation in formulations of nanotechnology-based smart drug/vaccine delivery systems is beginning to change the landscape of future medicines. They are being designed to overcome biological barriers in the living system by improving the delivery and efficacy of traditional therapeutics and reducing the toxicity by specificity to target cells/tissues. This review focuses on basic understanding and progress in the field of nanomedicine (especially nanocarriers-based drug and vaccine delivery), including nanoformulation of Amphotericin B with functionalized carbon nanotubes for the therapy of visceral leishmaniasis.