Search Results Heading

MBRLSearchResults

mbrl.module.common.modules.added.book.to.shelf
Title added to your shelf!
View what I already have on My Shelf.
Oops! Something went wrong.
Oops! Something went wrong.
While trying to add the title to your shelf something went wrong :( Kindly try again later!
Are you sure you want to remove the book from the shelf?
Oops! Something went wrong.
Oops! Something went wrong.
While trying to remove the title from your shelf something went wrong :( Kindly try again later!
    Done
    Filters
    Reset
  • Discipline
      Discipline
      Clear All
      Discipline
  • Is Peer Reviewed
      Is Peer Reviewed
      Clear All
      Is Peer Reviewed
  • Item Type
      Item Type
      Clear All
      Item Type
  • Subject
      Subject
      Clear All
      Subject
  • Year
      Year
      Clear All
      From:
      -
      To:
  • More Filters
9 result(s) for "Ntsendwana, Bulelwa"
Sort by:
Enhanced optical and electrochemical properties of FeBTC MOF modified TiO2 photoanode for DSSCs application
In this work, iron based 1, 3, 5-tricarboxylic acid (FeBTC) was prepared via microwave-assisted method and incorporated into TiO 2 via ultrasonic assisted method. The TiO 2 –FeBTC nanocomposites were characterized by XRD, FTIR, Raman, BET, FESEM, HRTEM, TGA, UV‒vis DRS and PL to understand their crystallographic, surface morphology, and optical characteristics. The Raman spectra showed a blue shift of E g , A 1g , and B 1g peaks upon incorporation of FeBTC MOF onto TiO 2 . HRTEM and XRD analysis confirmed a mixture of TiO 2 nanospheres and hexagonal FeBTC MOF morphologies with high crystallinity. The incorporation of FeBTC onto TiO 2 improved the surface area as confirmed by BET results, which resulted in improved absorption in the visible region as a results of reduced bandgap energy from 3.2 to 2.84 eV. The PL results showed a reduced intensity for TiO 2 –FeBTC (6%) sample, indicating improved separation of electron hole pairs and reduced recombination rate. After fabrication of the TiO 2 –FeBTC MOF photoanode, the charge transfer kinetics were enhanced at TiO 2 –FeBTC MOF (6%) with Rp value of 966 Ω, as given by EIS studies. This led to high performance due to low charge resistance. Hence, high power conversion efficiency (PCE) value of 0.538% for TiO 2 –FeBTC (6%) was achieved, in comparison with other loadings. This was attributed to a relatively high surface area which allowed more charge shuttling and thus better electrical response. Conversely, upon increasing the FeBTC MOF loading to 8%, significant reduction in efficiency (0.478%) was obtained, which was attributed to sluggish charge transfer and fast electron–hole pair recombination rate. The TiO 2 –FeBTC (6%) may be a good candidate for use in DSSCs as a photoanode materials for improved efficiency.
Electrospun PCL‐Based Materials for Health‐Care Applications: An Overview
Polycaprolactone (PCL) is one of the durable polymers with potential in a plethora of healthcare applications. Its biological properties, degradability, chemical properties, and mechanical properties can further be modified to manufacture desired products for modern biomedical applications. Electrospinning of PCL offers the opportunity to design treatment materials that resemble human tissues and facilitate regeneration at the target site. The resultant materials can also be modified by loading other active functional materials to broaden their applications. Herein, the recent advances in the preparation and modification of PCL‐based materials for healthcare applications are elucidated. The challenges and future trends for its application in modern biomedical applications are also outlined. Polycaprolactone (PCL) excels in healthcare due to its adaptable properties. Tailoring its biology, degradation, chemistry, and mechanics allows the crafting of diverse medical products. Electrospinning of PCL creates tissue‐mimicking materials promoting regeneration. Further enhancements by adding other functional elements increase its potential. This article explores recent advancements in modifying PCL‐based materials for healthcare applications.
Evaluation of Advanced Nanomaterials for Cancer Diagnosis and Treatment
Cancer is a persistent global disease and a threat to the human species, with numerous cases reported every year. Over recent decades, a steady but slowly increasing mortality rate has been observed. While many attempts have been made using conventional methods alone as a theragnostic strategy, they have yielded very little success. Most of the shortcomings of such conventional methods can be attributed to the high demands of industrial growth and ever-increasing environmental pollution. This requires some high-tech biomedical interventions and other solutions. Thus, researchers have been compelled to explore alternative methods. This has brought much attention to nanotechnology applications, specifically magnetic nanomaterials, as the sole or conjugated theragnostic methods. The exponential growth of nanomaterials with overlapping applications in various fields is due to their potential properties, which depend on the type of synthesis route used. Either top-down or bottom-up strategies synthesize various types of NPs. The top-down only branches out to one method, i.e., physical, and the bottom-up has two methods, chemical and biological syntheses. This review highlights some synthesis techniques, the types of nanoparticle properties each technique produces, and their potential use in the biomedical field, more specifically for cancer. Despite the evident drawbacks, the success achieved in furthering nanoparticle applications to more complex cancer stages and locations is unmatched.
Exploring Copper Oxide and Copper Sulfide for Non-Enzymatic Glucose Sensors: Current Progress and Future Directions
Millions of people worldwide are affected by diabetes, a chronic disease that continuously grows due to abnormal glucose concentration levels present in the blood. Monitoring blood glucose concentrations is therefore an essential diabetes indicator to aid in the management of the disease. Enzymatic electrochemical glucose sensors presently account for the bulk of glucose sensors on the market. However, their disadvantages are that they are expensive and dependent on environmental conditions, hence affecting their performance and sensitivity. To meet the increasing demand, non-enzymatic glucose sensors based on chemically modified electrodes for the direct electrocatalytic oxidation of glucose are a good alternative to the costly enzymatic-based sensors currently on the market, and the research thereof continues to grow. Nanotechnology-based biosensors have been explored for their electronic and mechanical properties, resulting in enhanced biological signaling through the direct oxidation of glucose. Copper oxide and copper sulfide exhibit attractive attributes for sensor applications, due to their non-toxic nature, abundance, and unique properties. Thus, in this review, copper oxide and copper sulfide-based materials are evaluated based on their chemical structure, morphology, and fast electron mobility as suitable electrode materials for non-enzymatic glucose sensors. The review highlights the present challenges of non-enzymatic glucose sensors that have limited their deployment into the market.
Electronic and equilibrium properties of molybdenum disulphide: Density Functional Theory study
Electronic and equilibrium properties of molybdenum disulphide (MoS2) were investigated using the full potential all electrons linearized augmented plane waves method. Both local density and generalized gradient approximations were explored to obtain the most stable configuration. Both approximations conform to the indirect narrow energy band gap in the neighbourhood of the Fermi level. Electronic band structure suggests a narrow energy band gap of 1.35 and 1.30 eV respectively for the local density and generalised gradient approximations. Density of states suggest a valence bandwidth of ±3.560 eV by both approximations. Minimum energy of -2.65 x 10 5 eV and equilibrium volume of 724 (Bohr) 3 were also recorded. Acquired computations agree well with related calculations.
Recent advances in nitrogen-doped graphene oxide nanomaterials: Synthesis and applications in energy storage, sensor electrochemical applications and water treatment
This review covers recent advances on production techniques, unique properties and novel applications of nitrogen-doped graphene oxide (NGO). The focal point is placed on the evaluation of diverse methods of production for NGO and reduced nitrogen-doped graphene oxide (NrGO) nanosheets using GO and graphite as carbon precursors. Variation in chemical composition of GO with variable N content, C–N bonding configurations and chemical reactive functionalities of NGO allow tuneable properties that render NGO a suitable material for various applications such as lithium-ion batteries, biosensors, supercapacitors and adsorption processes. NGO and NrGO exhibit significantly different performances compared to GO even with small amounts of N-doping. The type of C–N bonding and surface chemistries on the NGO are responsible for their unique electrical, mechanical, adsorption, chemical reactivity, photocatalytic activity, and optical properties. Various investigative techniques used to study NGO nanomaterials are also reviewed. Finally, future perspectives of NGO in this rapidly developing area are discussed. Graphical abstract Methods of synthesis of N-doped graphene oxide nanosheets and their advantages and disadvantages.
Enhanced optical and electrochemical properties of FeBTC MOF modified TiO 2 photoanode for DSSCs application
In this work, iron based 1, 3, 5-tricarboxylic acid (FeBTC) was prepared via microwave-assisted method and incorporated into TiO via ultrasonic assisted method. The TiO -FeBTC nanocomposites were characterized by XRD, FTIR, Raman, BET, FESEM, HRTEM, TGA, UV‒vis DRS and PL to understand their crystallographic, surface morphology, and optical characteristics. The Raman spectra showed a blue shift of E , A , and B peaks upon incorporation of FeBTC MOF onto TiO . HRTEM and XRD analysis confirmed a mixture of TiO nanospheres and hexagonal FeBTC MOF morphologies with high crystallinity. The incorporation of FeBTC onto TiO improved the surface area as confirmed by BET results, which resulted in improved absorption in the visible region as a results of reduced bandgap energy from 3.2 to 2.84 eV. The PL results showed a reduced intensity for TiO -FeBTC (6%) sample, indicating improved separation of electron hole pairs and reduced recombination rate. After fabrication of the TiO -FeBTC MOF photoanode, the charge transfer kinetics were enhanced at TiO -FeBTC MOF (6%) with Rp value of 966 Ω, as given by EIS studies. This led to high performance due to low charge resistance. Hence, high power conversion efficiency (PCE) value of 0.538% for TiO -FeBTC (6%) was achieved, in comparison with other loadings. This was attributed to a relatively high surface area which allowed more charge shuttling and thus better electrical response. Conversely, upon increasing the FeBTC MOF loading to 8%, significant reduction in efficiency (0.478%) was obtained, which was attributed to sluggish charge transfer and fast electron-hole pair recombination rate. The TiO -FeBTC (6%) may be a good candidate for use in DSSCs as a photoanode materials for improved efficiency.
Enhanced stability and efficiency of Pd electrocatalysts towards electrooxidation of ethanol using CNT–CNF supporting materials
Pd electrocatalysts supported on carbon nanotubes (CNTs) and carbon nanofibres (CNFs) and their combination thereof were evaluated for their effective ethanol oxidation reaction. The electrocatalysts (namely Pd/CNT, Pd/CNF and Pd/CNT-CNF) were synthesized and characterized using BET, TEM, XRD, TGA and Raman spectroscopy techniques. Electrochemical characterization using cyclic voltammetry in the presence of [Fe(CN) 6 ] 3/−4 redox probe showed that the electrocatalysts exhibited excellent current response on glassy carbon electrode in the order of Pd/CNT > Pd/CNF > Pd/CNT-CNF. In contrast, in alkaline ethanolic solution, the order of oxidative current response was Pd/CNF < Pd/CNT < Pd/CNT-CNF, implying better electrocatalytic activity for the ternary electrocatalysts. The superiority of Pd/CNT-CNF over other electrocatalysts was further revealed using chronoamperometry (current density: 51.52, 13.31 and 11.25 mA cm −2 for Pd/CNT-CNT, Pd/CNF and Pd/CNT, respectively). Furthermore, the ternary electrocatalysts demonstrated excellent stability after 1500 cycles, making it attractive as a durable electrode for fuel cell technology development. Graphical abstract
PAMAM templated N,Pt co-doped TiO2 for visible light photodegradation of brilliant black
This study examined the photocatalytic degradation of an azo dye brilliant black (BB) using non-metal/metal co-doped TiO2. N,Pt co-doped TiO2 photocatalysts were prepared by a modified sol-gel method using amine-terminated polyamidoamine dendrimer generation 0 (PG0) as a template and source of nitrogen. Structural, morphological, and textural properties were evaluated using scanning electron microscopy coupled to energy-dispersive X-ray spectroscopy (SEM/EDX), high-resolution transmission electron microscopy (HRTEM), X-ray diffraction spectroscopy (XRD), X-ray photoelectron spectroscopy (XPS), thermal gravimetric analysis (TGA), Fourier transform infrared (FTIR), Raman spectroscopy (RS), photoluminescence (PL) and ultra-violet/visible spectroscopy (UV-Vis). The synthesized photocatalysts exhibited lower band gap energies as compared to the Degussa P-25, revealing a red shift in band gap towards the visible light absorption region. Photocatalytic activity of N,Pt co-doped TiO2 was measured by the reaction of photocatalytic degradation of BB dye. Enhanced photodegradation efficiency of BB was achieved after 180-min reaction time with an initial concentration of 50 ppm. This was attributed to the rod-like shape of the materials, larger surface area, and enhanced absorption of visible light induced by N,Pt co-doping. The N,Pt co-doped TiO2 also exhibited pseudo-first-order kinetic behavior with half-life and rate constant of 0.37 and 0.01984 min−1, respectively. The mechanism of the photodegradation of BB under the visible light irradiation was proposed. The obtained results prove that co-doping of TiO2 with N and Pt contributed to the enhanced photocatalytic performances of TiO2 for visible light-induced photodegradation of organic contaminants for environmental remediation. Therefore, this work provides a new approach to the synthesis of PAMAM templated N,Pt co-doped TiO2 for visible light photodegradation of brilliant black.