Emission Analysis Of Pr[sup 3+]: PVP And Nd[sup 3+]: PVP Films

Abstract

Here we report on the results concerning the absorption and emission spectra of RE 3+ (Pr 3+ or Nd 3+ ) doped PVP polymer films. The absorption spectrum of Pr 3+ : PVP polymer film has shown three absorption bands at 444nm ( 3 H 4 → 3 P 2 ), 469nm ( 3 H 4 → 3 P 1 ) and 481nm ( 3 H 4 → 3 P 0 ). From the Pr 3+ : PVP polymer film, an emission at 603 nm ( 1 D 2 → 3 H 4 ) has been observed with an excitation at 443 nm ( 3 H 4 → 3 P 2 ). The absorption spectrum of Nd 3+ : PVP polymer film has exhibited eleven absorption bands at 324 nm, 383 nm, 432 nm, 462 nm, 511 nm, 526 nm, 580 nm, 686 nm, 746 nm, 799 nm, and 869 nm which are assigned to the electronic transitions of 4 I 9/

Thermally and photoinduced structural and chemical changes of a silver nanocube array on Au(111)

“…One can note that the decrease in G band intensity stems from the decrease in the amount of nanocarbons. According to the previous TGA studies, 49–52 nanocarbons start to desorb from the sample at around 400 °C. However, it was reported that almost 33% of nanocarbons remains on the metal nanoparticles after annealing at 500 °C.…”

“…A previous thermal gravimetric analysis (TGA) of a pure PVP film in nitrogen atmosphere revealed a large reduction in mass due to decomposition and desorption of PVP at around 400 °C. 49–52 Furthermore, Borodko and co-workers performed Raman spectroscopy and reported that the PVP covering on PtNP was converted to nanocarbon at 300–350 °C in the presence of oxygen or hydrogen. 46,53 A comparison of the present result with those in the previous studies indicated that the decomposition of PVP was completed at a temperature higher than 265 °C.…”