This term was rather frustrating overall. Following protocols based in multiple papers, an efficient and effect method for fabricating the MnO2 nanoneedles was developed. After multiple mostly successful attempts at producing needles, after reviewing literature it was determined the largest factors determining crystal growth and structure are time and concentration of water. By keeping a more precise eye on how long the reaction proceeded and on how much water went into solutions, the highest quality product was yielded. Another important thing to keep in mind is processing of the product. Washing the product twice, once with IPA (isopropyl alcohol) and a second in DI water should remove remaining reagents and impurities. It has also been found that lightly heating the product will prevent clumping and make it easier to handle. Larger glassware has been purchased and the hope is that next time far more product will be produced. This term also saw the first completion of the synthesis of silver nanowires. Over the summer three trials were conducted, all ending in failure: the first was lost when centrifuge tubes shattered, in the second run bad reagents were used leading to unusable products, and in the third the product was embedded in a teflon tube due to sonication. The most recent attempt was successful (with products pictured right). By carefully handeling fresh reagents and preparing solutions with as much precision as possible, a high yield of silver nanowires were produced. The trick here was making sure the autoclave is properly tightened, that there is a trace amount of catalyst (iron iii chloride), and that the correct amount of capping agent is present (polyvinylpyrolidone). Preliminary SEM imaging (not shown) shows clear wire formation inline with literature. The next step for the project is to cast ternary films, this will be undertaken over the winter break and explained in detail in a future post.
