Researcher:
Ertaş, Fatma Sinem

Profile Picture
ORCID

Job Title

Master Student

First Name

Fatma Sinem

Last Name

Ertaş

Name

Name Variants

Ertaş, Fatma Sinem

Email Address

Birth Date

Filters

2012 - 20153

Advanced Search

Filter by

Settings

Researcher Of Publications: search.filters.isAuthorOfPublication.fa872775-5764-42f6-9a4f-aa9026a9e0c9

Search Results

Now showing 1 - 3 of 3
  • Placeholder
    PublicationMetadata only
    Ultrasound assisted deposition of silica coatings on titanium
    (Elsevier, 2012) N/A; N/A; N/A; N/A; Kaş, Recep; Ertaş, Fatma Sinem; Birer, Özgür; Master Student; Master Student; Researcher; Koç University Surface Science and Technology Center (KUYTAM) / Koç Üniversitesi Yüzey Teknolojileri Araştırmaları Merkezi (KUYTAM); Graduate School of Sciences and Engineering; Graduate School of Sciences and Engineering; N/A; N/A; N/A; N/A
    We present a novel ultrasound assisted method for silica coating of titanium surfaces. The coatings are formed by "smashing" silica nanoparticles onto activated titanium surface in solution using intense ultrasonic field. Homogeneous silica coatings are formed by deposition of dense multiple layers of silica nanoparticles. Since the nanoparticles also grow during the reaction, the layers of the coatings have smaller particles on the substrate and larger particles towards the surface. The thickness of the coatings can be controlled with several experimental parameters. Silica layers with thickness over 200 nm are readily obtained.
  • Placeholder
    PublicationMetadata only
    Ultrasound-assisted hexamethylenetetramine decomposition for the synthesis of alpha nickel hydroxide intercalated with different anions
    (Springer, 2015) N/A; N/A; N/A; (TBD); N/A; (TBD); Ertaş, Fatma Sinem; Öztuna, Feriha Eylül Saraç; Ünal, Uğur; Birer, Özgür; Master Student; Researcher; Faculty Member; Researcher; Koç University Surface Science and Technology Center (KUYTAM) / Koç Üniversitesi Yüzey Teknolojileri Araştırmaları Merkezi (KUYTAM); Graduate School of Sciences and Engineering; Graduate School of Sciences and Engineering; College of Sciences; N/A; N/A; N/A; 42079; N/A
    Alpha nickel hydroxide was prepared by the sonochemical degradation of hexamethylenetetramine at elevated temperatures using chloride, acetate, nitrate, and sulfate nickel salts. This method yielded dense layered structures with two different interlayer spacing of 11 and 8 . The specific capacitance of these samples was further improved by the addition of extra anions to the reaction mixtures in the form of sodium salts. This approach yielded structures in flowerlike morphology with a single interlayer spacing of 8 . The sulfate-intercalated sample, however, formed the flowerlike morphology even without the addition of extra anions. The highest specific capacitance value of 543 F g(-1), at a scan rate of 50 mV s(-1), was obtained for sulfate-intercalated sample with extra anions. The differences due to different anions likely arise from size of their solvation shells and the distance between the anions and hydroxide layer. Anions surrounded tightly by water molecules are located farther from the hydroxide layers, interact less strongly and therefore are more labile and lead to higher specific capacitance values.
  • Placeholder
    PublicationMetadata only
    Sonochemical synthesis and electrochemical characterization of alpha-nickel hydroxide: precursor effects
    (Springer, 2013) N/A; N/A; Department of Chemistry; N/A; Department of Chemistry; Ertaş, Fatma Sinem; Kaş, Recep; Ünal, Uğur; Birer, Özgür; Master Student; Master Student; Faculty Member; Researcher; Koç University Surface Science and Technology Center (KUYTAM) / Koç Üniversitesi Yüzey Teknolojileri Araştırmaları Merkezi (KUYTAM); Graduate School of Sciences and Engineering; Graduate School of Sciences and Engineering; College of Sciences; N/A; N/A; N/A; 42079; N/A
    Sonochemical degradation of urea was employed to synthesize alpha-nickel hydroxide from different nickel salts. Utilization of ultrasound yielded products with properties significantly different than the products obtained by thermal degradation of urea. the effect of intercalating chloride, nitrate, Acetate, and sulfate anions on morphology and electrochemical performance was studied. the sulfate-intercalated sample had the smallest interlayer spacing when obtained by the sonochemical method, contradicting all the previous thermal synthesis results. the specific capacitance trend also differed from the literature values, and the value for the sulfate-intercalated sample was larger than that of acetate-and nitrate-intercalated samples. Ultrasonic synthesis increased the specific capacitance of the sulfate-intercalated sample significantly. This sample was also the most reversible and had the highest charge efficiency.