Silver nanoprisms grown into structural colors by high power LEDs

How to chemically synthesize silver nanoparticles, then grow them into triangular nanoprisms with light from a variety of LEDs. Each color LED creates a different size nanoprism, which has its own characteristic color.

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CMDITR video: https://www.youtube.com/watch?v=agD5jfXua-o 

Multispectral LED driver on Github: https://github.com/benkrasnow/MultiSpectLED 

Chemicals sourced from Amazon/eBay 

LR-1 spectrometer: https://www.aseq-instruments.com/LR1.html 

Micropipette set: https://www.amazon.com/gp/product/B06XJY82N3/ https://www.amazon.com/gp/product/B01KO7MCCC/ 

20ml glass vials with PTFE lined cap (do not use metal-lined): Environmental Express APC1675P Already gone from Amazon 

pH pen (this cost more than I remember, but it works really well, and has lasted many years. Cheaper pH pens are often pretty bad) https://www.amazon.com/gp/product/B01ESYG6B0/ 

Comparison of CD, DVD, Blu-ray discs with electron microscope: https://twitter.com/BenKrasnow/status/615327472909840385 

Great way to find related papers: https://www.connectedpapers.com/ 

Research sources: https://www.youtube.com/watch?v=agD5jfXua-o 

https://sci-hub.se/https://doi.org/10.1002/anie.200604637 

https://sci-hub.se/10.1038/nature01937 

https://sci-hub.se/10.1126/science.1066541 

https://sci-hub.se/10.1002/smll.200801480 

https://sci-hub.se/10.1039/b302943c 

https://opg.optica.org/oe/fulltext.cfm?uri=oe-20-28-29923&id=247745 https://www.rsc.org/suppdata/nr/c4/c4nr06901c/c4nr06901c1.pdf 

https://sci-hub.se/10.1039/C4NR06901C 

https://sci-hub.se/10.1155/2018/1781389 

https://www.cytodiagnostics.com/pages/silver-nanoparticles-handling-and-storage 

Support Applied Science on Patreon: https://www.patreon.com/AppliedScience

Olestra (zero calorie cooking oil) - chemical synthesis and taste test

I synthesized olestra from biodiesel, sugar, and soap with a sodium metal catalyst. I also describe some of the history of olestra's development.







Procedure that I used (Example 1) https://patents.google.com/patent/US3963699A/en 

Other resources: https://patents.google.com/patent/US20060047109A1/en

https://patents.google.com/patent/US4611055A/en 

https://sci-hub.se/https://doi.org/10.1021/ed068p476 

Biodiesel: https://www.e-education.psu.edu/egee439/node/684 

https://extension.okstate.edu/fact-sheets/biodiesel-production-techniques.html 

https://www.youtube.com/watch?v=3anau83Qxt4 

Epogee fat substitute: https://www.epogee.com/the-technology 

https://healthsmartfoods.com/products/sweet-nothings-low-fat-chocolate-covered-caramel 

Potassium oleate soap synthesis: https://lipidlibrary.aocs.org/documents/LipidsLibrary/Book%20II_ch03.pdf 

Studies on gastro distress and calorie compensation: https://sci-hub.se/https://doi.org/10.1046/j.1467-789X.2002.00050.x 

https://sci-hub.se/10.1006/rtph.1997.1164 

https://sci-hub.se/10.1001/jama.279.2.150 

Anal leakage MadTV: https://www.youtube.com/watch?v=Tx9LSEjgQxY 

Support Applied Science on Patreon: https://www.patreon.com/AppliedScience

X-ray timelapse of fluid movement in plants, stop-motion animation, sensor teardown/repair

I repaired a large digital x-ray detector and used it to record timelapse and stop-motion animations of plants, a clock, and a camera lens.

Applied Science X-ray backscatter imaging system: https://www.youtube.com/watch?v=H7ldYhzKAp4

Applied Science CT scanner: https://www.youtube.com/watch?v=hF3V-GHiJ78 

Geiger counter: https://mightyohm.com/blog/products/geiger-counter/ 

Linistepper motor driver: http://www.massmind.org/techref/io/stepper/linistep/lini_use.htm 

Potassium iodide: https://www.amazon.com/dp/B01JKJWXBK 

GE Rhythm user guide: https://www.bakerhughesds.com/sites/g/files/cozyhq596/files/2018-07/rhythm_rt_manual_english_rev_e.pdf 

Octave (open source MATLAB alternative): https://www.gnu.org/software/octave/index 

Mouse movement recorder software: https://sourceforge.net/projects/mousecontroller/ 

Octave and Arduino code used in this video: https://drive.google.com/drive/folders/1vM6KSc_EhrKc8J92Yn_-PE-lZhL3gkhA?usp=sharing 

Thank you for your support on Patreon: https://www.patreon.com/AppliedScience 

Thank you, Amir, for the X-ray sensor and software!

Underwater laser cutting and silver sintering to make ceramic circuit boards

 

Thermal stress cracking can be completely avoided by CO2 laser cutting thin alumina sheets underwater.  I also show how to formulate and apply silver paste, then sinter in a kiln to produce double-sided ceramic printed circuit boards with conductive vias.

60W CW CO2 laser at 80% power.  10mm/sec.  Standard lens focal length (50mm).  2mm water above ceramic.  180 passes to cut through 0.75mm thick alumina.  

Silver paste: 97% silver powder, 3% glass powder by mass.  Particle size 1 micron or less. Add poly vinyl alcohol mold release until desired consistency reached.

Paste applied with 4 mil thick vinyl stencil.  Dried in air 10 minutes, then rapidly brought up to 900*C, held for 10 minutes, then rapidly brought back down to room temperature.  Total cycle about 45 minutes.

I measured electrical conductivity of the finished traces from my process with vinyl stencils: 4 milliohms per square at 10 micron final thickness.  This is pretty close to the Dupont published spec ( less than 2 milliohm/sq at 16 micron thick)

Underwater CO2 laser cutting reference: https://sci-hub.se/10.1016/J.JEURCERAMSOC.2011.06.015

60W laser cutter: https://www.ebay.com/itm/294386493292

Ceramic sheets at McMaster: https://www.mcmaster.com/alumina/nonporous-alumina-ceramic-sheets-and-bars/

Ceramic PCB prototypes: https://ceramic-pcb.com/product/alumina-pcb-al2o3-pcb-prototypes-online/

Quickfire kiln: https://kruegerpottery.com/products/par_quikfire6

Raspberry Pi picoReflow oven controller: https://apollo.open-resource.org/mission:resources:picoreflow

Silver powder: https://www.ebay.com/itm/122525930519

Glass glaze: https://www.amazon.com/dp/B0044SCR6O

Macor: https://www.mcmaster.com/materials/material~glass-mica-ceramic/

Dupont silver paste: https://www.dupont.com/content/dam/dupont/amer/us/en/transportation-industrial/public/documents/en/LF131.pdf

Binders for ceramic powder: https://digitalfire.com/article/binders+for+ceramic+bodies

PVA mold release: https://www.tapplastics.com/product/fiberglass/mold_releases/tap_pva_mold_release_liquid/67

Applied Science on Patreon: https://www.patreon.com/AppliedScience

Atomic Layer Deposition of copper - If you like sputtering, you'll love this!

 

An explanation and demo of atomic layer deposition (ALD) of copper metal on glass.  Precursors are copper(I) chloride and hydrogen, processed in a hot-wall tube quartz tube furnace.

10 torr operating pressure

500 sccm argon sweep/purge gas constantly flowing

75 sccm CuCl argon pulse gas (17 seconds including flow controller lag)

100 sccm H pulse gas (14 seconds including flow controller lag)

7 second purge time between pulses

100mm quartz tube furnace diameter 

415*C deposition temperature

350*C CuCl evaporation temperature

Substrates are mostly borosilicate glass cleaned with RCA clean

The "good" samples shown in the video are about 750 cycles (about 9 hours

Main ref:

https://sci-hub.se/https://doi.org/10.1002/cvde.19970030107

Also helpful:

https://sci-hub.se/https://doi.org/10.1063/1.5087759

https://sci-hub.se/10.1149/2.0261501jss

https://sci-hub.se/https://doi.org/10.1016/0022-0248(92)90191-K

Alicat flow controller manuals (hard to find via website navigation):

https://documents.alicat.com/manuals/DOC-MANUAL-MC.pdf

https://documents.alicat.com/manuals/old/Gas_Flow_Controller_Manual_rev7.pdf

https://documents.alicat.com/Alicat-Serial-Primer.pdf

RCA clean: https://en.wikipedia.org/wiki/RCA_clean

CuCl synthesis: http://wwwchem.uwimona.edu.jm/lab_manuals/c1901exp35.html

Support Applied Science on Patreon: https://www.patreon.com/AppliedScience