Guava seeds synthesized silver nanowires
Contents
Guava synthesis of the Ag-NW
This experiment is composed with two existed paper, one is to synthesis AgNWs with Psidium Guajava seed, and the other one is to synthesis transparent conductive layer by transferring AgNWs which are light sintered by Riso print Gocco lamps. Guava seeds contain some compounds, such as polyphenols and alkaloids, which can reduce silver nitrate under certain conditions, thereby promoting the growth and stability of silver nanowires. These compounds acted as reducing agents and stabilizers during the preparation process, thus enabling a green synthesis method without external stabilizers. For the light sintering of AgNWs, a local Japanese toy kit "RISO PRINT GOCCO LAMP" is used to replace the IPL (intense pulsed light) in the original paper. The sintered AgNWs is formed on glass and then be transferred to a PVB film.
Experiments
The experiment process is introduced below in the gallery. The process aims to repeat the result introduced in the paper "UV-Light Mediated Biosynthesis of Silver Nanowires; Characterization, Dye Degradation Potential and Kinetic Studies". The first attempt was made in BioClub Tokyo. Additionally, 3 groups of mixtures with different concentration of guava seed extraction was prepared: 1. silver nitrate solution mixed with distilled water, 2. silver nitrate solution mixed with guava seed extraction heat stirred for 50 mins, 3. silver nitrate solution mixed with guava seed extraction heat stirred for 4 hours. All beakers are put under UV exposure for 4 hours, the color of the second and 3rd mixture were changed from milky white to orange. The orange solution and the aggregations were collected separately, but only the solution was examined by the UV-vis spectrum in Tokyo.
- step by step process
The seeds was extracted from guava purchased in Taiwan.
The seeds was firstly dried in oven at 50ºC for 48 hours and then powdered by grinder pestle without filtering.
Mix 0.1g of the guava seed powder with 100ml distilled water, and it's stirred with heat stirrer at 40ºC for 50 minutes.
Prepare 1mM silver nitrate solution by dissolving 1.7 grams of silver nitrate crystals in 100 ml of distilled water. Stir it in room temperature until the solution turns clear.
Mix the silver nitrate solution and guava extraction by the ratio of 2:1.
The mixed solution was put into an UV chamber and was exposure for 4 hours in room temperature. All beakers are sealed with cling film.
The change of the color of the final solutions after UV exposure.
The final solution was filtered with filter paper and the color is in orange.
The UV-vis spectrum comparism
The result of UV-Vis spectrum data can be downloaded here.
- UV-vis spectrum result
UV-vis analytic chart was made and supported by Shohei Asami, member BioClub Tokyo.
UV-vis graphs of the orange final solution and clear final solution.
UV-Vis graphs of P. Guajava extraction and Ag-NWs from the paper.
SEM photography
The scanning electron microscopy is kindly supported by Joakim Reuteler in ETH Zurich. Two samples were prepared, the first one is the final solution drop dried on glass, the second is the aggregations collected from the centrifuged final solution. There's no sign shows the existence of the wire-alike shape, indicating the failure of the nano wire synthesis with guava seeds extraction. Only "flake-alike" shape was found in the sample.
- SEM result
Centrifuged final solution.
The final solution and the prepared sample for SEM. The right one on glass is the drop of solution, the left one is the aggregation from the centrifuge.
The SEM photograph of the aggregated sample under 50 µm..
The SEM photograph of the aggregated sample under 10 µm..
Part II, Gacco Lamp Sintered AgNWs PVM film (on going)
Continued with the first part, in the original paper, the AgNWs is sintered by IPL (intense pulsed light) but due to the high price of IPL, I decided to try something else. I found a type of light bulb that generate sudden high heat in a Japanese toy kit RISO PRINT GOCCO LAMP which is introduced by the founder of Bioclub, Georg Tremmel. The original purpose of the bulb is to create mask for riso print. The original usage please visit RISO PRINT GOCCO LAMP tutorial. The follow on practices is documented in page Conductive thin coating made of AgNWs.
- Print GOCCO lamp
Prin Gocco lamp with the printing case.
Gocco lamp installed in the lamp case.
Close-up photo of the Gocco lamp.
Preferences
- Ali, Faisal, Zahid Ali, Umer Younas, Awais Ahmad, Ghulam Mooin Ud Din, Muhammad Pervaiz, Rafael Luque, et al. 2021. “UV-Light Mediated Biosynthesis of Silver Nanowires; Characterization, Dye Degradation Potential and Kinetic Studies.” Sustainability 13 (November): 13220. https://doi.org/10.3390/su132313220.
- Lv, Pengfei, Huimin Zhou, Min Zhao, Dawei Li, Keyu Lu, Di Wang, Jieyu Huang, Yibing Cai, Lucian Amerigo Lucia, and Qufu Wei. 2018. “Highly Flexible, Transparent, and Conductive Silver Nanowire-Attached Bacterial Cellulose Conductors.” Cellulose 25 (6): 3189–96. https://doi.org/10.1007/s10570-018-1773-8.
- Ferraro, Giovanni, and Emiliano Fratini. 2019. “A Simple Synthetic Approach To Prepare Silver Elongated Nanostructures: From Nanorods to Nanowires.” Journal of Chemical Education 96 (3): 553–57. https://doi.org/10.1021/acs.jchemed.8b00628.
- Padhi, Santwana, and Anindita Behera. 2022. “Chapter 17 - Biosynthesis of Silver Nanoparticles: Synthesis, Mechanism, and Characterization.” In Agri-Waste and Microbes for Production of Sustainable Nanomaterials, edited by Kamel A. Abd-Elsalam, Rajiv Periakaruppan, and S. Rajeshkumar, 397–440. Nanobiotechnology for Plant Protection. Elsevier. https://doi.org/10.1016/B978-0-12-823575-1.00008-1.
- Lee, Dong Jun, Youngsu Oh, Jae-Min Hong, Young Wook Park, and Byeong-Kwon Ju. 2018. “Light Sintering of Ultra-Smooth and Robust Silver Nanowire Networks Embedded in Poly(Vinyl-Butyral) for Flexible OLED.” Scientific Reports 8 (1): 14170. https://doi.org/10.1038/s41598-018-32590-0.
- Jin, Hwa-Young, Jae-Yup Kim, Jin Ah Lee, Kwangsoo Lee, Kicheon Yoo, Doh-Kwon Lee, BongSoo Kim, et al. 2014. “Rapid Sintering of TiO2 Photoelectrodes Using Intense Pulsed White Light for Flexible Dye-Sensitized Solar Cells.” Applied Physics Letters 104 (14): 143902. https://doi.org/10.1063/1.4871370.
