Jump to content

Clea

Members
  • Posts

    7
  • Joined

  • Last visited

Everything posted by Clea

  1. I checked Polymer Source prices, but it is still unaffordable considering my application (cheap, simple sensors). Admittedly I've never heard of 'microphase separation' and 'block copolymers' till two weeks ago and ' ATRP' till today. I didn't ask my university friends yet. I found a paper on its synthesis 'Synthesis of Functional Poly(styrene)-block-(methyl methacrylate/ methacrylic acid) by Homogeneous Reverse Atom Transfer Radical Polymerization: Spherical Nanoparticles, Thermal Behavior, Self-Aggregation, and Morphological Properties' (Pizarro, G. C. et al., 2013) but it involves lots of things I don't understand and more work than I care to do. I think I'll drop the idea altogether and use something more straightforward. like carbon nanotubes. Looking up how to make CNTs cheaply and simply. Thank you
  2. I'm sorry that my question is vague. I have edited the original post. Thanks
  3. I am a postgraduate and (will) have access to a lab. I want to synthesize a block copolymer, (maybe PS-b-PMMA?) The block copolymer should microphase separate to form a nano-array domain which I then intend to use as a template to deposit another polymer, (probably polypyrrole, or PEDOT?) This link should help convey my intention http://www.sigmaaldrich.com/technical-documents/articles/material-matters/use-of-block-copolymers-in-nanoscale-patterning.html I cannot afford to buy the block copolymer, and I am wondering if it's possible to synthesize it myself in the lab. I have no experience in this and this is more of an exploratory thing to me.
  4. I suppose that competing cations will not be reduced unless they have a greater standard electrode potential than the cation I'm interested in reducing.Am not particularly concerned about the product obtained in the anode side unless it is rate limiting (which I don't know yet btw). Haven't gave much thought on the role of the KCl other than simply filing it under 'to increase conductivity,' The electrolyte should have enough ions to carry charge to the anode/cathode to balance the charge on both sides so the cathode doesn't get a backlog of electrons on it, and the anode, excess holes. Actually I only have a glassy carbon and a Pt rotating tip, so I was making do with what I've got. Which is fine really, because the process corrodes Sn fairly quick and I'd end up with a damaged expensive rotating Sn tip. Commercial Sn foils should have some impurities such as Pb etc which may poison or interfere with my process.
  5. I am trying to eletrochemically reduce CO2 into HCOO-/HCOOH at a rotating Sn cathode. I used a 1M KOH anolyte and CH3OH with a lil bit of water(as a proton donor) catholyte. I also added in KCl to improve conductivity. Did preelectrolysis and bubbled N2 into the catholyte for an hour plus minus. Did a pretty good job at reducing graph noise and ghost peaks. Then I pumped in CO2 for another hour. I used a pretty low flowrate though, as the electrolyte will spit out if I set it any higher. The bubble size and flowrate are not unlike the ones produced in a fish tank The Sn cathode I used is Sn plated on glassy carbon. The quality is pretty bad as I only deposited it from a 4M HCl + 0.01M SnCl2.2H20 catholyte and 0.5M H2SO4 anolyte. It corrodes very very much faster than I'd like it to and I have to keep redepositing it every now and then. Ran linear sweep voltammetry at 0 to -2 V vs Ag/AgCl but I couldn't get any reduction curve other than for H2 evolution which kicks off at -1.5 V. I am at a loss. I've tried 1. Drastically increasing the rotating speed 2. Switching out the Ag/AgCl reference electrode with another one. 3. Repeating the work many times all for naught. It is ironic because when I used a water catholyte, it worked just fine. Can you guys help brainstorm of other things I can try? Thanks Now thinking back, I am starting to suspect it's the KCl salt. The KCl didn't really dissolve in my methanol. But then I dissolved the same amount of salt in another catholyte with 50% water content and nothing happened to that one either.
  6. Clea

    Nernst Equation

    Hi, I have a question about the meaning of the nernst potential. say for a reaction A + B = C + D with a caculated nernst potential of -0.5 Does it mean that if I apply a potential of -0.4, the reaction will move forward, i.e. produce C and D?
  7. Hi all, I want to reduce carbon dioxide into formic acid via electrolysis with a tin or carbon rotating cathode I plan to use glycerol carbon dioxide solution as my catholyte. But i looked online and found no-one uses glycerol, but methanol instead. Glycerol is a better solvent compared to methanol and it is also less toxic. So why don't we use glycerol? Is there something I'm not aware of?
×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.