Browsing by Author "Acidereli, H."

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Biocatalysis: Fundamentals and Solvent Parameters
(Elsevier, 2020) Acidereli, H.; Sogut, E.G.; Mustafov, S.D.; Gulcan, M.; Sen, F.
Biocatalysis involves the use of one or more enzymes to catalyze chemical reactions. Compared to conventional methods, biocatalysis has advantages such as high stereo-, regio-, and chemoselectivity, efficient catalysis, both complex and straightforward transformations, low rate of by-product formation, inexpensive refining and purification (uncomplicated), mild reaction conditions, and reduced impact on the environment by reducing waste production. To have these advantages, the solvent character of the enzyme should be optimally determined. Thus, all the advantages of biocatalysis are utilized. In this review, it has been tried to present the parameters that will provide optimum conditions for biocatalysis. Biocatalysis, which facilitates many disciplines, is the most popular subject in the catalysis field due to its unique facilities and still undiscovered features. © 2021 Elsevier Inc. All rights reserved.
Magnetic Nanoparticles
(Elsevier, 2020) Acidereli, H.; Karataş, Y.; Burhan, H.; Gülcan, M.; Şen, F.
Magnetic nanoparticles (MNPs) have widespread attention because of their unique features. For a few decades, growing development in chemical synthesis of nanomaterials and material surface modification have been seen and performed in numerous applications including biomedicine, biotechnology, catalysis, magnetic chemistry thermoelectric materials, etc. Various methods for fabrication of MNPs which have a controllable size, distribution, and surface modification have been reported. In these methods, several techniques containing irradiation, microwave, ultrasonication, vapor deposition, electrochemical, and microwave are applied to produce MNPs either in bottom-up or top-down processes. Generally, magnetic synthesis of nanoparticles is carried out by using these two processes. Nanomaterials with magnetic properties have wide applications in many fields such as biology, medicine, and engineering. In this section, the recent developments in the structures, occurrences, most commonly used samples, and common areas of use of the MNPs are given. © 2021 Elsevier Inc. All rights reserved.
A Novel Highly Active and Reusable Carbon Based Platinum-Ruthenium Nanocatalyst for Dimethylamine-Borane Dehydrogenation in Water at Room Conditions
(Nature Research, 2020) Karatas, Y.; Acidereli, H.; Gulcan, M.; Sen, F.
In this paper, we present platinum/ruthenium nanoparticles supported on Vulcan carbon (PtRu@VC) as a nanocatalyst for the dehydrogenation of dimethylamine-borane (DMAB) in aqueous solution under mild conditions. PtRu@VC nanocatalyst was fabricated using the alcohol-reduction techniques which is a facile and effective method. The prepared PtRu@VC nanocatalyst exhibited a good stabilization and an effective catalytic activity for hydrogen evolution from the DMAB dehydrogenation in water at room temperature. The composition of PtRu@VC nanocatalyst was investigated using different analytical techniques inductively coupled plasma optical emission spectroscopy (ICP-OES), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HR-TEM), powder X-ray diffraction (P-XRD) and X-ray photoelectron spectroscopy (XPS). A monodispersedPt/Ru metals distributions on VC (as supporting material) were revealed by TEM and HR-TEM analyses. The mean particle size of PtRu@VC nanocatalyst was found to be 3.15 ± 0.76 nm. XPS analysis for PtRu@VC nanocatalyst showed that almost Pt-Ru metals were found to be the metallic state. Catalytic experimental results showed that PtRu@VC nanocatalyst has a high catalytic activity with an excellent turn-over frequency (TOFinitial) value of 14926.2 h−1 (248.77 min−1) in the dehydrogenation of DMAB in water at room temperature. Additionally, in the paper, we report some different kinetic data obtained from different experimental parameters of temperature, catalyst and substrate concentrations conducted for DMAB dehydrogenation in water catalyzed with PtRu@VC nanocatalyst. © 2020, The Author(s).
Polymer-Based Nanomaterials To Use in Hydrogen Acquisition and Hydrogen Energy Storage
(Elsevier, 2020) Nas, M.S.; Calimli, M.H.; Acidereli, H.; Karatas, Y.; Gulcan, M.; Sen, F.
Energy demand has increased dramatically worldwide due to population growth. This is because almost all activities take place through energy. The majority of the energy used is derived from fossil sources. The use of fossil-based energy causes pollution to the environment and these resources cannot be recycled. Compared to renewable energy sources, fossil-source energy sources are much cheaper but they increase environmental pollution. Among renewable energy sources, hydrogen is seen as a highly effective resource. With the combustion of hydrogen, there are no chemicals that can be harmful to the environment, and its energy capacity is higher than other energy sources. Numerous studies have been carried out as an alternative to conventional storage methods for the safe storage of hydrogen. In this context, many studies have been carried out by scientists to develop new chemical hydrogen storage materials and to prepare and identify new heterogeneous catalyst systems that produce hydrogen from these materials. Hydrogen can be obtained from various materials such as formic acid and amine-borane (ammonia-borane, methylamine-borane, dimethylamine-borane, and hydrazine borane) compounds in liquid and solid form have a very important place. To release hydrogen from these materials, generally, some suitable catalysts are used. Catalysts are prepared using supporting materials like carbon and carbon derivations with different preparation methods to obtain high catalytic activity catalysts. In this chapter, nanomaterials composed of carbon and carbon derivations as catalysts to obtain hydrogen from hydrogen sources are evaluated. © 2021 Elsevier Inc. All rights reserved.