Creating Upconversion Fluorescent Material Through Solution Combustion Synthesis
0:00 Introduction to the goal of the video: to synthesize a material that exhibits upconversion fluorescence, emitting higher-energy visible photons (red and green) upon excitation with lower-energy infrared photons.
0:44 Material focus: Herium and urbium-doped utrium oxide.
1:19 The lanthanides' F orbitals have complex geometry which shields them from the environment. Electrons can be excited between these F orbitals, creating long-lived excited states, enabling upconversion.
2:18 How it works: One photon excites an herium ion, followed by re-excitation with a second photon. The emitted photon has higher energy than the two input photons, achieving upconversion.
3:00 The pairing of utopium and erbium ions is effective because urbium absorbs light at 980 nm and passes the energy to the herium.
3:34 Upconversion nanoparticles have applications in biosensing (due to infrared transparency in biological tissues) and solar harvesting (converting unused infrared light into usable energy).
5:14 Methodology: Solution combustion synthesis will be used, where rare earth materials are turned into oxidizers, mixed with fuel, and ignited to form oxide particles.
5:54 Process: Create nitrate salts, set them on fire, and heat them. A 980 nm laser will be used to test the upconversion fluorescence.
5:54 Method (cont): The reaction follows a specific paper that calls for an anal step at 800 degrees celcius.
6:29 Self-promotion: The narrator notes that his Patreon is moving to a monthly system in order to better support his goal of monthly uploads.
6:29 Rare Earth elements: Herum, utrium, and erbium will be used, sourced from Pete several years ago. They will be dissolved to create nitrate salts.
10:02 The rare earth metals are slowly dissolved into water before small volumes of nitric acid are added to assist the dissolving process.
12:50 Food dehydrator used to dry the solutions, despite previously being used to dry McDonald's. The goal is to crystallize the solutions, with an ultimate result of some crystals and clear pink utopium nitrate.
15:37 A week later, a sample is retrieved from a dessicator, which helps dry the substance to be used.
16:43 The glycine is combined with the utrium nitrate and irium, before it's dissolved into water.
19:19 Reviewing relevant literature on the synthesis for proper instructions.
19:38 Reference Paper methodology: metal nitrates are combined with glycine, then preheated into a muffle furnace heated to 450 degrees.
21:02 Alternative method: Use an open flame on a hot plate as an alternative to the furnace.
21:41 Combusting in the open: The liquid solution is boiled on a hot plate before an open flame is used. The ultimate product is a turd-like powder of the relevant oxide.
23:10 Grinding the powder outside to avoid breathing weird oxide particles, though the presenter also notes that he is curious if the substance lights up already with the laser.
24:11 A 500mW 980nm laser is used (purchased for $75) to test the upconversion nanop particles.
25:50 The Narrator jokes about his expectations for the $75 purchase.