Copper Oxide Formation - Science topic

After melting the copper-aluminium in furnace, the black layer(copper oxide ) has formed on the surface.

which chemicals are useful to clean the oxidized layer?

hi all,

i use Cu particles in size of 1 micrometer to make a film.

i sinter the film at 600 in air and then reduce the oxidised Cu to metal state at 300 in pure h2 or H2/Ar atmosphere.

i noticed that the particles collapse after this process and the film becomes very unstable. i don't understand why spherical Cu particles lose their shape and become much smaller after this. film is mostly unstable after reduction.

any comment or method to avoid this is appreciated.

thanks

What can be a possible explanation for observing increasing oxygen vacancies in a metal oxide film (eg: Cu2O) deposited using ALD or CVD when the deposition temperature is increased?

As I understand, greater reactivity with water at higher deposition temperatures should result in fewer oxygen vacancies.

Thank you.

When performing a synthesis of CuO-doped TiO2 nanoparticles through sol gel process (alkoxide path; ethanol as solvent), a bluish green sol and a green intermediate product (dried gel) were obtained. I came across a few threads on forums and in wikipedia stating that the green intermediate product is actually ''basic copper nitrate'' (Cu2(NO3)(OH)3). However i fail to find any reliable literiture confirming this claim.

What is/could be the identity of this green intermiediate product? Can anyone explain in detail the reaction path of thermal decomposition of hydrated copper (II) nitrate?

The synthesis steps (rough description):

1) preparation of a sol --> bluish green sol

2) gelation --> bluish green gel

3) drying in fume box (24h around 18 °C) --> green (emerald green) crystal-like solid

4) drying in oven (24h at 120°C) --> dark green crystal-like solid

5) calcination (8h at 300°C) --> black crystal like solid (assumed to be CuO trapped in TiO2 network)

the products for each step during the synthesis are shown in the attach images

Multiple compositions of Cu-Mo thin films (produced by sputtering, 1000 nm thick) were heat treated (ranging from 0% Mo to 100% Mo) with a tube furnace under argon gas (750 degrees Celcius, 10 hours). However, the argon gas flow nor the chamber pressure was not able to be determined due to equipment limitations.

However, I noticed that upon examining the films with XRD, the pure copper film (0% Mo) exhibit the formation of copper (I) oxide.

Meanwhile, the thin films containing molybdenum did not form copper (I) oxide at all, but rather, only molybdenum (IV) oxide.

Taking a look at an Ellingham diagram (https://imgur.com/a/IrwJ8, also attached), the region above the Cu2O line is "Region A", the region between the Cu2O and MoO2 lines is "Region B", while the area under the MoO2 line is "Region C".

My questions are....

If the reaction were to occur at Region A (where oxygen partial pressure is enough to form both Cu2O and MoO2), shouldn't there be traces of Cu2O in the heat treated Cu-Mo films?

If the reaction were to occur at Region B (where oxygen partial pressure is enough to form MoO2, but too low to form Cu2O), shouldn't Cu2O not form on the pure copper film, since the partial pressure is too low to form Cu2O? Even if the pure copper film had already oxidized prior to the heat treatment, wouldn't the Cu2O on the film decompose (due to being an unstable phase due to the lack of oxygen partial pressure) as the heat treatment progresses?

I synthesize the emeraline base polyaniline according to Macdiarmid and keep it in a glass vessel for a long time. But now I see a different behavior. I guess maybe it was a environmental effect (especially moisture).  

Basically I would like to prepare a copper/zinc/alumina catalyst from metal nitrates precursors dissolved in ethanol. Ethylenediamine will be used as a complexing agent. Do you think it is safe to calcine the resulting metal ethylenediamine complex at around 350 oC? What are the possibilities of side reactions happening and resulting in a fire or small explosion?

Thank you !

Hi,

I prepared CuO Nanostructures with rough surface on copper substrate, and i have reflection data and it is difficult to measure the thickness of my sample,  so which way is better to calculate band gab.  

thanks, 

I would like to know if there is a reason for these twin peaks in my XRD. The starting material is CuO with hydrazine as the reducing agent. End product is metallic Cu. 

i want to remove copper oxide layer of copper particles. 

as i know, acetic acid can remove copper oxide layer. 

then, i just put copper into acetic acid?

Besides there are so many UV peaks and these results are not in accordance with the results of other researchers in any way. XRD patterns show formation of pure CuO and ZnO particles but I am not satisfied with the results of UV. I have performed it several times but got the same results. CuO showed peaks at 270 and 273 while ZnO showed peaks at 290 and 320.

I am working with CuO nanoparticles. I had synthezed CuO nanoparticles Using Water Extract Of Plant and Characterized their properties with SEM-EDX. From EDX data revealed that my nanoparticles is still containing carbon sulfur, and the other mineral. I want to remove the carbon sulfur, and the other mineral then I can get pure CuO nanoparticles. And I have problem my obtained CuO nanoparticle sticky in media filter paper when the proses dried at temperature room for 24 hour.

How to convert copper ii oxide to copper?

Hello experts on FTIR,

I have deposited copper oxide films on glass substrate. I want to identify the FTIR absorption bands at arround 865,1100, 2155 and 2233 cm-1.

thank you 

I want to prepare CuO nanoparticles in side poly vinyl alcohol network. When ever i am trying to react copper ions in PVA solution with naOH, I am getting Green precipitate.This is copper hydroxidce but not CuO. May I know if some body had any solution to prevent this and getting nanoparticles.

Hi,

how can we explain the formation of copper oxides (CuO and Cu2O) by the decomposition of copper nitrate Cu(NO3)2.3H2O at higher temperatures (350 for exemple). one can give the chemical reaction?

the used deposition device is spray pyrolysis.

What are the optimum condition for synthesis Cuo and ZnO nanoparticules? nthesis of nanoparticles?

I need to create CuO surface for which the CuO unit cell is need to be cleaved along stable orientation.

I am interested to learn whether there are predictable differences in the characteristics of copper oxide (CuO) nanoparticles stemming from combustion vs wet chemistry synthesis methods and if yes what those would be (references are welcome).

now people are using cu as interconnecting layers but cu gets oxidized very easily so how they are avoiding this.

I am trying and study the Fehling's test in solution using the UV-Vis spectroscopy. The test involves the precipitation of red solid particles of Cu₂O owing to the redox reaction of a reducing sugar and Cu(II) ions in an alkaline medium. I want to determine the spectroscopic characteristics/differences between free Cu(II) ions and Cu(I) oxide. I have performed some (cuvette) measurements using a NanoDrop 2000/2000c Spectrophotometer but all my spectra are very noisy especially in the UV range (190-380 nm) despite the high absorbance (A_max=2.5) of all my samples. As an example, I cannot even ascertain how many peaks are present due to the noise.

Does anyone know if the problem could be due to the instrument (high scan speed, just 3 seconds per analysis) or if there is any mistake in my operating procedure?

When I etching the CuO on Cu2O samples by FeCl3+HCl, CuCl always appears on the surface. Then how to remove the CuO properly?

I want to deposit CuO on Co3O4 and I cannot figure out which method I should use.

If possible then can anyone suggest me the experimental conditions for the annealing???

I reduced CuO and Cu(OH)2 separately into Cu and performed FTIR. I want to make sure no traces of Cu-O or CuO-H bond remains in the final material. How can I analyze the FTIR spectra (attached file) of final Cu sample?

I'm synthesizing CuO at pH below neutral. In order to sort out mechanism when I see literature mostly CuO NPs are produced at higher pH by 2 step mechanism. First production of Cu(OH)2 and then conversion to CuO. In my case I don't get any evidence of Cu(OH)2 from XRD and XPS analysis of ppt. 

So I wonder whether my reaction follows a different mechanism or I just don't get Cu(OH)2  in precipitate due to low pH ?

Can anyone please help sort out this problem? What can be the possible routes for synthesis of CuO at acidic pH without involving Cu(OH)2 as an intermediate?

I excited CuO nanoparticles at 320nm and it gave the above three peaks.

We synthesized single phase Cu2O and CuO need to take into application part, so it will be very helpful if you can share your valuable points and thoughts.

I use azo dye having sulphonic as an anchoring group. Pure dye was absorbed at 600nm, while hybrid material was absorbed at 560nm.