Water-soluble non-polymeric electrospun cyclodextrin nanofiber template for the synthesis of metal oxide tubes by atomic layer deposition

Çelebioğlu, Aslı; Vempati, Sesha; Özgit-Akgün, Çaǧla; Bıyıklı, Necmi; Uyar, Tamer

doi:10.1039/c4ra12073f

Cited by 48 publications

(43 citation statements)

References 30 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…XRD patterns from core-shell as well as hollow samples match with the literature and confirm the wurtzite structure [10,18,36,54,55]. Overall, the peaks became sharper as a result of the calcination process, which increased the crystallinity in contrast to the hollow ZnO fibers produced by washing the core [53]. Also the results from XRD corroborate with that of local crystal investigation from TEM.…”

Section: Resultssupporting

confidence: 78%

“…Note that the lower diameter is equivalent to higher specific surface area when compared to the substrate with fibers of 650 nm diameter. To compare, ı • with the hollow samples produced by washing the core did not show significant change [53] in contrast to the present samples. When the CS 80 nm sample is subjected to calcination, the polymer core is removed and the lattice spends the gained thermal energy in relaxing and increasing its crystallinity.…”

Section: Resultsmentioning

confidence: 50%

“…During the thermal treatment the polymer core is decomposed while the inorganic coating (ZnO) is subjected to some changes in its crystallinity. These changes are significant when compared to the hollow samples produced by washing the core [53]. Changes in the crystallinity have significant implications on the optical properties as we will see later in this report.…”

Section: Resultsmentioning

confidence: 66%

“…The percentage decrease is ∼43 and ∼40 for 80 nm and 650 nm samples, respectively. It is interesting to note that in the case of hollow samples produced by dissolving the 'core' hosted relatively higher O Ch fraction [53]. The phenomenon of chemisorption of oxygen is complex as it can occupy a variety of places on the surface.…”

Section: Resultsmentioning

confidence: 99%

See 3 more Smart Citations

Transformation of polymer-ZnO core–shell nanofibers into ZnO hollow nanofibers: Intrinsic defect reorganization in ZnO and its influence on the photocatalysis

Kayacı

Vempati

Özgit-Akgün

et al. 2015

Applied Catalysis B: Environmental

Self Cite

View full text Add to dashboard Cite

a b s t r a c tPhotocatalytic activity (PCA) on semiconductors is known to be majorly influenced by specific surface area and intrinsic lattice defects of the catalyst. In this report, we tested the efficiencies of 1D ZnO catalysts of varying fiber diameter (80 nm and 650 nm of inner diameter) in two formats, viz. core-shell and hollow nanofibers, where the former is calcined to yield the latter. These nanofibrous catalysts were produced by combining electrospinning and atomic layer deposition processes which were then subjected to thorough characterization including photoluminescence (PL) unveiling the details of intrinsic defects/densities. During the thermal treatment, intrinsic defects are reorganized and as a result a new PL band is observed apart from some significant changes in the intensities of other emissions. The densities of various intrinsic defects from PL are compared for all samples and juxtaposed with the PCA. Careful scrutiny of the various results suggested an anti-correlation between surface area and PCA; i.e., higher surface area does not necessarily imply better PCA. Beyond a limit, the most deterministic factor would be the density of surface defects rather than the specific surface area. The results of this study enable the researchers to fabricate 1D semiconductor photocatalysts while striking the balance between surface area and density of defects.

show abstract

Section: Resultssupporting

confidence: 78%

Section: Resultsmentioning

confidence: 50%

Section: Resultsmentioning

confidence: 66%

Section: Resultsmentioning

confidence: 99%

See 2 more Smart Citations

Transformation of polymer-ZnO core–shell nanofibers into ZnO hollow nanofibers: Intrinsic defect reorganization in ZnO and its influence on the photocatalysis

Kayacı

Vempati

Özgit-Akgün

et al. 2015

Applied Catalysis B: Environmental

Self Cite

View full text Add to dashboard Cite

show abstract

“…In this context atomic layer deposition (ALD) is a very good choice, where ZnTiO 3 can be obtained through sequential deposition of ZnO and TiO 2 followed by a regular thermal treatment. Furthermore, ALD can yield complex architectures down to nanoscale with an excellent compositional control and high homogeneity at molecular level [8][9][10][11][12] in contrast to conventional solid-state or sol-gel methods which essentially yield powder or thin lms. Layer-bylayer formation of ALD can inhibit the secondary phase formation/segregation during thermal treatments, which is an essential step for the preparation of titanates.…”

mentioning

confidence: 99%

Surface ionic states and structure of titanate nanotubes

et al. 2015

Self Cite

View full text Add to dashboard Cite

Here we present an investigation on Zn-Ti-O ternary (zinc titanate) nanostructures which were prepared by a combination of electrospinning and atomic layer deposition. Depending on the ZnO and TiO 2 molar ratio, two titanates and one mix phased compound were synthesized by varying the post-annealing temperatures. Specifically Zn 2 TiO 4 , ZnTiO 3 and ZnO/TiO 2 nanostructures were fabricated via thermal treatments (900, 700, 800 C, respectively). Structural studies unveiled the titanate phase of the nanostructures. Furthermore, the ionic states of the titanate nanostructures on the surface are revealed to be Ti 3+ and Zn 2+. Spin-orbit splitting of Zn2p and Ti2p doublets were, however, not identical for all titanates which vary from 23.09-23.10 eV and 5.67-5.69 eV respectively. Oxygen vacancies were found on the surface of all titanates. The valance band region was analyzed for Zn3d, Ti3p, O2s and O2p and their hybridization, while the edge (below Fermi level) was determined to be at 2.14 eV, 2.00 eV and 1.99 eV for Zn 2 TiO 4 , ZnTiO 3 and ZnO/TiO 2 respectively.

show abstract

General Strategy for Fabrication of Ordered One Dimensional Inorganic Structures by Electrospinning: Structural Evolution From Belt to Solid via Hollow Tubes

et al. 2021

Self Cite

View full text Add to dashboard Cite

Increasing profound interest in methods to fabricate complex hollow superstructures in terms of shell architecture is highly desirable for the realization of various functionalities. Recent efforts in this direction have strongly suggested that unlike other hollow structures, tubular structures do not have well-developed nanostructure library, and establishing a general method remains a significant challenge. Hollowstructured metal oxides have emerged as one of the most propitious functional materials by virtue of their hollow interior, shell composition, internal structure, low density, high surface area, and fast diffusion ability. [1][2][3][4] These solitary and exceptional characteristics have made them outstand in various fields including catalysis, chemical sensors, adsorption, and energy conversion/storage systems. [5][6][7][8][9][10][11][12] The recent past has significantly seen dimensionally controlled structures to be drawing recognition because of their correlation between the structure and property in surfaceenhanced applications. In this aspect, intensive efforts have taken place to develop diverse approaches for assembling hollow structures to optimize their physicochemical properties for specific applications. Consequently, this has been upheld through varied synthesis routes and numerous hollow structures such as spheres, boxes, and micro/nanotubes have been fabricated. [13,14] To raise the value of appropriate functionalities and exploit the structural advantages in surface-enhanced applications, welldefined shell structures with tunable size, shape, composition, and pores are highly desirable. However, most of the reported hollow structures possess relatively simple configuration which strongly limits their prospects to modulate potential characteristics. This remains as a substantial challenge to structural aspects including the shell thickness, number of internal multishells, porosity, and importantly unsuitable for large-scale synthesis. Among the different methods for preparing the hollow structures, template-assisted synthesis has been recognized as a straightforward method because of the predictability of the resultant shapes originating from the sacrificed templates. [15][16][17][18] Although the templating strategy has enabled the successful preparation of hollow structures; however, it still possess few critical challenges. They include the cost, tedious and timeconsuming coating procedure, nonuniformity of coating, reproducibility, additional steps to remove the template without collapsing the original structure, and scalability. Furthermore, the

show abstract

Water-soluble non-polymeric electrospun cyclodextrin nanofiber template for the synthesis of metal oxide tubes by atomic layer deposition

Cited by 48 publications

References 30 publications

Transformation of polymer-ZnO core–shell nanofibers into ZnO hollow nanofibers: Intrinsic defect reorganization in ZnO and its influence on the photocatalysis

Transformation of polymer-ZnO core–shell nanofibers into ZnO hollow nanofibers: Intrinsic defect reorganization in ZnO and its influence on the photocatalysis

Surface ionic states and structure of titanate nanotubes

General Strategy for Fabrication of Ordered One Dimensional Inorganic Structures by Electrospinning: Structural Evolution From Belt to Solid via Hollow Tubes

Contact Info

Product

Resources

About