PIGMENT RESEARCH PROJECT – FINAL REPORT REEL – RESEARCH EXPERIENCES TO ENHANCE LEARNING PURPOSE The final report details the findings of your research project. This information will be used to assess the scientific knowledge generated by your work and to guide future implementations of the project. It also serves as an exercise in scientific writing. ASSIGNMENT Components of the Report Your research results should be presented in the format of a scientific paper. It is not necessary to write in the third person, but the report should be written from an objective viewpoint (you should not report the results with a bias for one outcome over another). Use past tense to report results and present tense to discuss them. The report should be single spaced with bold headings to denote the beginning of each of the following sections. Title Authors Abstract Introduction Experimental Results Discussion & Conclusions Future Directions Acknowledgements (optional) References Your thoughts on the REEL Program Rough guidelines for each section of the report are given on the following pages. When preparing your report keep the following points in mind: (a) Each student is responsible for his or her own report, (b) While the data will be the same for the entire group, each student’s writing should be his or her own. Figures and Tables may be the same for all students in the group, the conclusions may also be similar, but the text should be unique. Directly copying any section of the report (other than figures and tables) from someone else in the group will be grounds for academic misconduct. SECTION GUIDELINES Title The title should be succinct, yet sufficiently descriptive to alert the reader as to the content of the project. For example, “Synthesis and Characterization of Ag3(VO4)1–x(PO4)x Pigments” Authors In scientific publishing all people who intellectually contribute to a project should be included as co-authors. List yourself as the first author, followed by the other members of your group. The last name in the author list should be your peer mentor. Abstract This is a short (50-100 words) summary of the goals and findings of the research project. Introduction The introduction describes the motivation for the research and describes the state of knowledge before the research project started. For this paper there should be a ½ to 1 page background on the pigment(s) you were seeking to replace. This should be followed by roughly ½ page describing what is known (prior to your research) about the end members of the solid solution you were exploring, including color and any relevant details you can find about the crystal structures (crystal system, space group, lattice parameters). You may want to include other details as you deem appropriate. Experimental The experimental part of a paper describes the procedures that were carried out. It should be sufficiently detailed to allow another researcher to repeat the experiment. In each project there were four parts to the procedure that need to be described: - Small scale precipitations in test tubes Synthesis of samples for characterization Structural and compositional analysis by X-ray powder diffraction Optical characterization by UV-Visible diffuse reflectance spectroscopy Your report should include 1 paragraph describing the results of the small scale precipitations that led your group to select the end members of your compositional series. Write net ionic equations for the precipitation reactions that you believe to be responsible for the precipitation of your end members. Describe the color and consistency of the end member precipitates that formed. If pH played any role in this process please describe it. Describe the procedures used for the synthesis of your samples (not the samples prepared by your group partners). Write a balanced equation for each of your samples. If you used a solid state synthesis route list the amount of each reactant and the annealing temperature. If there were multiple cycles of heating give full details. If you prepared samples by precipitation list full details of the precipitation (solutions used, including concentrations, volumes, order of mixing, special pH considerations, etc.). The X-ray diffraction and UV-Visible characterization were more or less the same for everyone involved. In one paragraph state that the structural and compositional characterization of the samples was carried out using X-ray powder diffraction (XRPD). The XRPD data was collected over a given two-theta range (look at your patterns to determine the 2-theta range) with a Rigaku Miniflex Diffractometer. The optical properties were characterized by UV-Visible diffuse reflectance spectroscopy using an Ocean Optics spectrometer equipped with a fiber optic diffuse reflectance probe. Once again here you should state the wavelength range that was employed. Results The results section is where you report the experimental findings, for this research project the results include: - The appearance of your samples. Describe the colors of the samples at each stage of the synthesis. Include the photograph(s) of the samples in your group’s compositional series as Figure 1. - The UV-Visible diffuse reflectance spectra. You should show the diffuse reflectance spectra of all samples in your group’s compositional series as Figure 2. Comment on whether the onset of absorbance is sharp (giving rise to bright colors) or smeared out over a wide range of wavelengths (usually leading to brown and other “muddy” colors). - If the onset of absorbance is reasonably sharp you will be able to calculate a band gap for each compound. Create a table, Table 1, which lists the color and band gap for each compound in your group’s compositional series. If you were able to successfully form a solid solution plot the band gap (on the y-axis) vs. the composition (on the x-axis). - The X-ray powder diffraction patterns provide information about the phase or phases present in your sample. Include the excel plot of the X-ray powder diffraction data as Figure 3. From the X-ray patterns you should identify which phases are present (including unreacted starting material, or undesired side products) for each compound in your group’s compositional series. Compile this information in Table 2. The phases in each sample should be identified by the name and stoichiometry given in the database. Discussion and Conclusions Unlike the experimental section where you simply present the experimental facts, this section is where you comment on what you think they mean. You should address the following points. - Did your synthesis work? For each samples did you (a) form a solid solution, (b) form a 2-phase mixture, (c) form undesired side products, (d) form an amorphous product, (d) end up with unreacted starting materials? What can you say about the phase diagram (a figure may be appropriate)? If the synthesis did not work as planned how might you modify the synthetic procedure to make it work (a brief discussion and reference to successful syntheses described in the literature would be appropriate)? - What electronic transition is responsible for the color? Is it a charge transfer transition on the anion or a d-to-d transition on the cation, or both. In either case it would be appropriate to show a MO diagram as a figure. Is the color of your compound consistent with the UV-Visible spectrum? Did your samples form a solid solution? Given the ionic radii of the cations (or anions) involved is this result expected? How did the color of your sample change from one end of the compositional series to the other end. What electronic factors do you think are responsible for this change. Would your compound make a good pigment? Future Directions Does your system show any promise as a pigment? Are there unanswered questions that were raised by your work? If you had more time what would be the next step in the research? Consider these points because I plan to take the take the most interesting questions raised by this year’s research and use them as starting points for next years research. Acknowledgements This section is optional, but it is appropriate to give credit for anyone else who assisted the research (either through ideas or action). This could include, but is not limited to, your TA, someone from another group, Dr. Woodward, a friend or family member. References Use numbered endnotes to reference information taken from journal articles, books and other sources (such as the web). A 10% penalty will automatically be applied to any report without references. Use the APA style for references as shown below: - Journal Articles: Author, A. A., Author, B. B., & Author, C. C. (Year). Title of article. Title of Periodical, volume number (issue number), pages. For example: Smith, J. C., & Patil, R. K. (2001). Synthesis of Ag3PO4. J. Inorg. Chem. 334(10), 655-672. - Books: Author, A. A. (Year of publication). Title of work: Capital letter also for subtitle. Location: Publisher. For example: Woodward, P. M. (2006). General Chemistry Students: Cheap Labor and Indentured Servitude. Columbus: Ohio State University Press. - Electronic Resources: At a minimum, a reference of an Internet source should provide a document title or description, a date (either the date of publication or update or the date of retrieval), and an address (in Internet terms, a uniform resource locator, or URL). Whenever possible, identify the authors of a document as well. (For more details see http://www.apastyle.org/elecmedia.html) Your Thoughts on the REEL Program This section is separate and not graded, but we would be interested to hear your comments on the following questions: 1. 2. 3. 4. 5. 6. 7. What aspects of this project did you like? What aspects of this project did you dislike? What are your feelings about the peer mentor aspect of the program? Would you advise future students to enroll in a REEL or a non-REEL Chem 123 course? What suggestions do you have for improving these labs? Would you be interested in returning as a peer mentor? Did this experience alter your views of how research and science in general work? Did it alter your desire to become involved in research If you want your comments to be anonymous feel free to give these comments to your TA on a separate sheet of paper without your name. Your comments are very valuable to us.