User:Materialsgirl9/sandbox

From Wikipedia, the free encyclopedia

This is my sandbox.

Titanium disulfide
General
CategoryMineral
Formula
(repeating unit)		TiS2
Crystal systemHexagonal central system
Identification
Formula mass111.99 g/mol
ColorTypically yellow
Crystal habitOctahedral
Density3.21 g/cm3
References[1]


Titanium disulfide
Names
IUPAC name
Titanium(IV) sulfide
Other names
Titanium Sulfide, titanium sulphide, titanium disulfide, titanium disulphide
Identifiers
EC Number
  • 232-223-6
UNII
Properties
TiS2
Molar mass 111.99 g/mol
Appearance yellow to green powder
Density 3.22 g/cm3, solid
Structure
hexagonal, Pearson symbol, space group P3m1, No. 164
octahedral
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
checkY verify (what is checkY☒N ?)

Titanium disulfide[edit]

Titanium disulfide is a golden, yellow solid [2] material with high electrical conductivity. Titanium disulfide is commonly used as a semiconductor in lithium and magnesium battery cathodes (TiS2 nanotubes paper), as its conductivity is increased when layers are formed with electron-donors such as alkali metals in a process called intercalation (chemistry). TiS2 has interesting material properties. The hexagonal close-packed structure is analogous to Cadmium iodide (CdI2) structure, with half of the octahedral holes filled with a cation [3]. This is a common structure of d-metal halides and d-metal chalcogenides [4]

Material Properties[edit]

1. high pressure studies support semimetal, not semiconductor

2. no significant change in density of state at Fermi level up to 20 GPa

3. transport properties change at 15GPa [5]

4.

Synthesis[edit]

Nanostructures[edit]

Many types of titanium disulfide nanostructures can be achieved through similar methods. Nanotubes, nanoclusters, whiskers, nanodisks, thin films and flower-like structures have been described. 1. Synthesis of nanotubes

2. Synthesis of nanoclusters

a. nanoclusters=quantum dots, unique electronic and chem.. properties beacause of quantum confinement and very large surface/volume ratios.

b. structure of common form: hexagonal layered structure; sheet of hcp metal between two sheets of hcp chalcogens (atoms within this layer are covalently bonded). Each metal ion is surrounded by 6 chalcogens as an octahedral structure.

c. nanoparticles achieved using micelle structures that create a template for the correct size growth. If nucleation is a controlled step, the desired size products can be achieved in a narrow distribution.

d. The following reagents were used as received: titanium tetrachloride (TiCl4, Aldrich), iron(II) sulphide 99% (Sigma, Australia), concentrated hydrochloric acid (32% w/w) (Asia Pacific Speciality Chemicals Limited, Australia), tridodecylmethyl ammonium iodide (TDAI).[6]

3. Synthesis of whiskers

a. Synthesis on Nickel coated Silicon wafers via simple vapor transport deposition at 630 degrees C

b. Properties of whiskers (Single crystalline, exact stoichiometric composition)

c. Theoretical and experimental opportunites for similar whisker arrays [7]

4. Synthesis of nanodisks

a. Physical properties of TiS2 dependent on number of layersdisks enhance properties

b. The orbital overlap of the atoms on the surface of each layer can have a significant influence on the resultant bandgap structure and this effect will be more significant as the number of layers decreases. Thus, it was theoretically anticipated that single-layered titanium sulfide would have semiconducting properties, while the bulk material would be semimetallic. TiCl4 and S, varying times, oleylamine solvent, 110degrees C [8]

5. Synthesis of thin films


6. Fullerenes

a. fullerene=closed-cage nanoparticles, synth using gas-phase synthesis

b. perfectly spherical structure, diameter btwn 60 and 80 nm, consisting of about 90 concentric layers.

c. spherical shape provides ‘rolling friction with a reduced friction coefficient and wear’ [9]

7. Synthesis of flower-like structures

a. control of injection temperature changes 2D to 3D(higher temp for 3D)

b. final morphology can be controlled by nucleation sites’ initial properties (flakes-instant nucleation, flowers-spherical nucleus)

c. synth: titanium tetrachloride with elemental sulfur in solvent 1-octadecene

d. highest surface area-flowers, better for hydrogen storage than flakes or even nanotubes [10]

Notes[edit]

  1. ^ Wan, C.L.; Wang, Y.F.; Wang, N.; Norimatsu, W.; Kusunoki, M.; Koumoto, K. J. Electronic Mat. 2011, 40 (5), 1271-1280.
  2. ^ Smart, Moore
  3. ^ [Smart, Moore]
  4. ^ [Shriver and Atkins Inorg. Textbook]
  5. ^ Bao, L.; Yang, J.; Han, Y.H.; Hu, T.J.; Ren, W.B.; Liu, C.L.; Ma, Y.Z.; Gao, C.X.; J. App. Phys. 2009. 109 (5).
  6. ^ Mainwaring, D. E.; Let, A. L.; Murugaraj, P. Solid State Commun. 2006, 140, 355.
  7. ^ Zhang, Y.; Li, Z.; Jia, H.; Luo, X.; Xu, J.; Zhang, X.; Yu, D. J. Cryst. Growth, 2006, 293, 124.
  8. ^ Park, K. H.; Choi, J.; Kim, H. J.; Oh, D.-H.; Ahn, J. R.; Son, S. Small. 2008, 7, 945.
  9. ^ Margolin, A.; Popovitz-Biro, R.; Albu-Yaron, A.; Rapoport, L.; Tenne, R. Chem. Phys. Lett. 2005, 411, 162.
  10. ^ Prabakar, S.; Bumby, C.W.; Tilley, R.D. Chem. Mater., 2009, 21 (8), pp 1725-1730

Materialsgirl9 (talk) 01:19, 28 September 2011 (UTC)

    • Peer Review**

1. Title?

a. Title not present

List of links to add:

a. Allen J. Bard

b. microfabrication

c. electrocatalyst

d. enzymes


2. Appropriate level of general public statement? Capture subject effectively?

a. Perhaps the authors should consider using less technical jargon and more simple sentences for the general public paragraph.

b. General public summary seems to capture the subject of the review effectively.


3. Background and Significance explain Importance? Context of Materials Field?

a. Two sentences in introduction describe the importance, that SECM provides topographical information and surface reactivity data.

b. The context in the materials field is that SECM is a technique for microfabrication, microstructuring, and surface patterning.


4. Outlined Areas Coherent and Logical? order?

a. I would put Instrumentation section before Principles of Operation; it will be easier to see how the variables relate to the data being measured by instrument.


5. Figures

a. Yes, planned figures of sample imaging and the instrumentation schematic should improve the article’s clarity.

b. I can’t think of any figures to add besides the planned ones.


6. Major Reviews missing?

a. Shigeru Amemiya, Allen J. Bard, Fu-Ren F. Fan, Michael V. Mirkin, and Patrick R. Unwin. Annual Review of Analytical Chemistry. 2008, 1, 95-131. doi: 10.1146/annurev.anchem.1.031207.112938


7. Effective language/Confusing sections?

a. describe who Engstrom is for 1986 experiment, including full name and/or link

b. typographical error: History Paragraph, “…experiments by Allen J. Bard’s using…”

c. Introduction: what’s a 2-D raster? Materialsgirl9 (talk) 19:33, 12 October 2011 (UTC)

7. Synthesis of flower-like structures

Three dimensional flower-like structures can be made by chemical vapor transport or by controlled wet chemical synthesis. Tao, et al., showed (100) crystalline growth by chemical vapor transport of powdered sulfur and titanium foil at 650-750°C with flower-like structures with notable field emission current [1] The micro-scale hexagonal plates had a border length of 7.8 µm and a thickness of 156 nm. Characterization was performed using XRD, SEM, EDS, and high-resolution TEM. Prabakar, et al., showed the wet chemical synthesis of titanium disulfide flower-like structures from reacting sulfur dissolved in 1-octadecene and titanium tetrachloride at 300°C [2]. Samples were characterized by SEM, TEM, EDS, and PXRD. Control of titanium tetrachloride injection temperature changes the structure between two- or three-dimensional nanostructures, from flake to flower. Two dimensional flakes were obtained at 150°C injection temperature. Final morphology can be controlled by nucleation sites’ initial properties. Flakes were shown to have instant nucleation, where flowers have a spherical nucleus. Flowers have the highest surface area, which makes them better for hydrogen storage than flakes or even nanotubes. Materialsgirl9 (talk) 21:36, 2 October 2011 (UTC)

  1. ^ Tao, Y.; Wu, X. Zhang, Y. Dong, L.; Zhu, J. Hu, Z. Cryst. Growth. Des. 2008, 8 (8), 2990-2994.
  2. ^ Prabakar, S.; Bumby, C.W.; Tilley, R.D. Chem. Mater., 2009, 21 (8), 1725-1730


Titanium disulfide as a cathode material. Lithium ions intercalate and deintercalate as the battery is charged and discharged.


The cadmium iodide structure of titanium disulfide.
The hexagonal close packed structure of titanium disulfide, reproduced from reference 8.






File:Image name
Caption

    • Peer Review**

I used the last version from November 22.

1. Title seems to encompass the entire site, but make sure that it is coded correctly. Links: Mesoporous, Racemization (in synthesis section)


2. Appropriate level introduction?

a. Perhaps begin with a basic description of what mesoporous means and what silicas in general are used for. Name examples of early mesoporous materials and which properties are specifically better. It is hard to put the usefulness of mesoporuous silica into perspective when the background information is not complete.

b. The following wording is not clear: “make them highly potential”


3. Background/Significance have sufficient context?

a. Give a better understanding of what mesoporous means and what they are used for up front before describing them in further detail.

b. Give more specific applications on a large scale. What type of devices are nanoscale clusters/wires of organosilicates used in?

c. You mention several properties of POMs that make them more/less desirable than zeolites, but those properties are never addressed later in the article. Perhaps you could add a Properties section.


5. Figures:

a. With the exception of the adsorption figure, figures are quite small; is it possible to make them appear larger without having to click the link?

b. The adsorption figure is helpful and is appropriate and helpful to grasp the concept. A caption may help elucidate how they are used for environmental remediation: are they discarded after adsorbing pollutants or can they be reused? What types of pollutants can be captured?

c. The bridging ligand figure does help the clarity of the section.


6. Missing references?

a. What are these “other refs” and what information did you get from them?

b. I believe articles cited in Wikipedia should have titles listed. If not, be consistent throughout.

c. Reviews:

i. Amirali, P.; Budi, H.S.; Frances S.; et al. Mesoporous silica nanoparticles for bioadsorption, enzyme immobilisation, and delivery carriers. 2011. NANOSCALE, 3 (7), 2801-2818.

ii. Satoru, F. and Shinji, I. Self-organization of organosilica solids with molecular-scale and mesoscale periodicities. 2008, Chem. Mat. 20 (3), 891-908.


7. Confusing sections:

a. Background and History, 2nd paragraph: Made useful mesoporous materials with organic groups that bind heavy metals…describe why it is useful to bind heavy metals explicitly. 3rd paragraph: would suggest ‘heterogeneity’ instead of ‘inhomogeneity.’ It would also be more clear if split into two sentences. Explain why only 25% organic content is not favorable.

b. Synthesis section is confusing. I would suggest subheaders for more clarity and easier reading. Is that the correct chemical name for TEOS? Comes up as tetraethylorthosilicate on Wikipedia. Either change chemical name or don’t include abbreviation.

c. Applications: Give examples of “larger molecules” or give a range of sizes? Catalysis section: perhaps give an example of which industrial processes use POMs or what chemicals are made. Explain why conventional acids are less environmentally friendly. State why anchored functional groups have higher catalytic activity or at least list a proposed reason why. Adsorption: This section could be expanded. Sensing: There are some typographical errors. Give specific examples of molecules that can be sensed or why these types of molecules need to be sensed.

d. Future: In the title, be consistent with capitalization.

Materialsgirl9 (talk) 22:58, 28 November 2011 (UTC)

Retrieved from "https://en.wikipedia.org/w/index.php?title=User:Materialsgirl9/sandbox&oldid=1146439252"