21 Questions 35 Answers 0 Followers
Questions related from Ramesh Vasan
I have fabricated an all-inorganic QLED with FTO/NiO/CdSeZns/ZnO/Al. It has three conduction regions corresponding to Ohmic, Trap limited and space charge limited (SCLC). I expect the device to...
10 October 2017 5,434 4 View
I have used a Si CCD detector setup to measure the electroluminescence of a LED. The y axis unit is given as counts/sec. I want to extract the output power density of the LED. Is there a way to...
09 September 2017 465 4 View
I want to measure the type and work function of Beta Gallium oxide. Unfortunately I dot not have access to UPS or Kelvin probe set up. Is there an indirect method to measure the work function of...
08 August 2016 4,968 3 View
What are the possible metal cations that can replace the existing lead in lead halide based perovskite material. There are reports of tin and antimony being studied as replacements. Can any other...
08 August 2016 5,343 5 View
I have CdSe/ZnS red emitting nanocrystals in chloroform. The PL peak of these nanocrystals is at 635 nm. When I mix the nanocrystal dispersion with nickel oxide nanoparticle powder and measure...
02 February 2016 6,033 3 View
I want to measure the PL decay time of CdSe/ZnS QDs spin coated on glass and nickel oxide thin film separately. Unfortunately, I do not have access to a time resolved PL system. I'm looking for...
02 February 2016 5,411 3 View
I have CdSe/ZnS quantum dots with oleic acid ligand in hexane solvent. As synthesized quantum dots were purified with excess of methanol and acetone in a centrifuge. I wish to isolate the quantum...
09 September 2014 9,750 10 View
I'm trying to deposit aluminum from a boron nitride crucible using an Ebeam evaporator at a pressure of ~5e-6 torr. When the metal melts, it starts boiling and bursts out globules of molten metal...
08 August 2014 3,227 9 View
I'm interested in measuring the band alignment of colloidal grown CdSe/ZnS nanocrystals. Is there a direct or indirect method to measure that?
07 July 2014 2,199 2 View
I wish to pattern ITO coated glass substrate for QDLED application using a RIE.
07 July 2014 2,984 3 View
The performance of colloidal QD solar cells or LEDs degrade with successive IV measurements. Specifically, the resistance of the device drops to few kOhms.
03 March 2014 2,716 6 View
I'm planning to deposit a thin layer (40-50 nm) of metal oxides on ITO coated glass slides. Can I use electron beam evaporation for this? I'm worried about the oxygen vacancies associated with...
02 February 2014 4,515 12 View
I measured the efficiency of an InAs/GaAs quantum dot solar cell under different input power from 0.5 to 4 sun in steps of 0.5. I found they do not change much. Efficiency under 0.5 sun was 11.3%...
02 February 2014 8,073 19 View
I have fabricated a colloidal quantum dot LED from CdSe/ZnS nanocrystals. The luminous intensity degraded with number of trials. The resistance of the device also reduced from few MOhm to few...
02 February 2014 4,385 4 View
I'm fabricating QD LEDs with metal oxide charge transport layers. The layers are either deposited using sputtering or spin coated from a sol gel. What should be the resistivity of such layers for...
01 January 2014 285 5 View
I'm trying to fabricate a QDLED using CdSe/Zns emission layer. I'm not able to form a good enough film of QD using spin coating or dip coating. If electrophoretic deposition can be used, what...
01 January 2014 6,238 2 View
I'm fabricating QD LED with a structure, ITO/HTL/QD emission layer/ETL/Ag. I deposit the HTL, QD emission layer and ETL using spin coating. When I deposit the metal contact, it short circuits with...
12 December 2013 6,011 3 View
Im fabricating QD LED with a structure, ITO/HTL/QD emission layer/ETL/Ag. I deposit the HTL, QD emission layer and ETL using spin coating. When I deposit the metal contact, it short circuits with...
11 November 2013 9,981 0 View
I'm in the process of fabricating colloidal quantum dot LED using layer by layer deposition. I wish to characterize the hole transport layer and electron transport layer before fabricating the device.
11 November 2013 6,889 0 View
I am fabricating quantum dot led using CdSe/ZnS nanocrystals as emission layer. The emission layer has to be few monolayers thick. I'm trying to spin coat the nanocrystal dispersions in chloroform...
11 November 2013 9,827 17 View
I have fabricated a QLED device FTO/NiO/CdSeZnS QD/ZnO nanoparticle/Al. When biased the emission is bright the instance I turn on the supply and die out immediately. Attached is the video of it.
01 January 1970 7,776 11 View
