Faculty Advisor: Dr. Dan Morse Research Mentors: Dr. Birgit Schwenzer, James Neilson

1. Basic OverviewKinetically Controlled Vapor Diffusion Synthesis Of Chromium Doped Indium Hydroxide Thin Films • Faculty Advisor: Dr. Dan Morse • Research Mentors: Dr. Birgit Schwenzer, James Neilson • RET Advisor: Dr. Martina Michenfelder • RET Participant: Jason Smith • RET research funding made possible by the National Science Foundation (NSF) • Morse Group Funding: The Defense Advanced Research Projects Agency (DARPA) and The Department of Energy (DOE)

2. Purpose • To create stable, crystalline films of indium oxide • To attain “tunable levels ” of chromium doping • Basic research T.Tomita, K.Yamashita and J.Yasui and Y.Hayafuji, “Electronic Structures of Indium Oxide with Point Defects” and Bull.Soc.Discrete Variational Xα, 16, O-2p09 (2003) (in press).

3. Potential Applicationsbeyond basic research • Memory devices and spin valves in the new frontier of “spintronics” • Semiconductors • Multiferroics • The unknown . .

4. What is a chromium doped indium hydroxide thin film? • It is just that. A thin film (thickness not yet determined ) • Forms on surface of aqueous solution given proper precursors and catalysts. • Somewhat resembles a lily leaf (no scientific relevance) in shape, color and location* ( *floating on aqueous solution).

5. Doping • Film framework (base material) is indium hydroxide • Doping = substitution chromium is substituted for indium (see schematic) • May result in unique electrical and magnetic properties • Annealing (heating) film may result in crystalline structure of indium oxide doped with chromium, the desired result Un-doped indium hydroxide Doped

6. Doping • A brief animation

7. Lingo • X-ray diffraction XRD • Scanning electron microscopy SEM • Energy dispersive spectroscopy EDS • Inductively coupled plasma spectroscopyICP • Carbon, hydrogen, nitrogen, analysis CHN • Indium nitrate hydrate In(NO3)3·XH2O • Chromium III nitrate Cr(NO3) 3 • Ammonium hydroxide NH4OH

8. Materials and MethodsGeneral Overview Remove films from wells, whole films are “washed”, “powders” are filtered Well plate placed in covered reaction box, over several hours thin films form indium nitrate hydrate, and the dopant chromium III nitrate, are added to top and bottom rows of wells of 12 well reaction plate (noted IC) Whole films analyzed by SEM/EDS for structure, elemental composition and % chromium incorporation Powders/ film fragments analyzed by XRD for crystallinity • solution of ammonium • hydroxide (noted N), • is added to middle wells CHN analysis ICP analysis

9. Materials and Methods • A 2nd brief animation

10. X-ray diffraction of thin film nanoparticles with varying Cr doping levels 10% 8% 6% 4% 2% 0% • XRD: Utilized as a method for determining crystallinity • Peak at (22°[2Ө]) corresponding to d spacing of 4.04 Å, indium • hydroxide’s most intensely scattering lattice plane • sharp peak indicates crystallinity, higher doping (10%) • results in amorphous background signal no sharp crystalline peak

11. EDS Data OverviewIn Conjunction With Qualitative Data • Low doping ( 2-4%) : macroscopically thin, brittle, films, predictable doping • High doping ( 10%) : macroscopically thick, stable films, unpredictable doping • 6% Cr doping: consistent film stability and dopant incorporation, averaged 5.17 at% (twelve experiments, forty-four data sets), candidate for further analysis

12. Lessons Learned • I learned that a thorough understanding only comes with thorough and complete analysis • I learned the importance of accuracy and attention to detail • I learned that patience is a virtue necessary for basic research • Peer reviews can be painful but enlightening

13. Special Thank You • To Dr. Martina Michenfelder for her endless patience and wisdom • To the staff of the MRL for making and creating such an outstanding opportunity for teachers • To the NSF for continuing its dedication to support science and exploration • To the Morse Group for a glimpse into biomimetic chemistry

14. Preliminary Conclusion • Indium hydroxide thin film chromium doping/ incorporation can be influenced by adjusting chromium levels of starting solution

15. Resources • Indium oxide structure (image 1) T.Tomita, K.Yamashita and J.Yasui and Y.Hayafuji, “Electronic Structures of Indium Oxide with Point Defects” and Bull.Soc.Discrete Variational Xα, 16, O-2p09 (2003) (in press). • Lily image courtesy of http://www.pirateplanet.com/