Indirect Nanoplasmonic Sensing

In a different approach, the sintering of selected and unselected clusters in an inert gas atmosphere under elevated temperatures was tested using the INPS platform at Chalmers. Recent results showed the successful use of this technique for investigating sintering phenomena of supported metal particles with an average size of 3.3 nm in situ at atmospheric pressure [39, 40]. 

In a first step the sensitivity of the method towards small clusters was studied, by monitoring the change in LSPR centroid wavelength for both a blank IMPS chip (reference) and a chip with 0.005 e/nm unselected Ptn S3 supported on SisN as a function of temperature. The samples were heated in an A r flow (200mL/min) from 325 K in steps of 15 K and held at one temperature for 45 min (after 15 min, 

In order to compare and unearth different sintering behaviors of selected and unselected cluster samples, the changes in relative peak position of three different Ptx,n = 68, 68 -I- 22, 53) samples (0.004 and 0.003 e/nm ) were probed. For these experiments, the reactor was pre-heated to 453 K (to guarantee fast temperature equilibration upon sample insertion) and each of the samples inserted and the signals recorded for 21 h under an Ar flow (200 mL/min). The samples where then taken out of the reactor and the procedure was repeated using the same samples under the exact 

In order to understand the changes in LSPR on the INPS chip on a local level, TEM windows with a SisN4 support were prepared with the same amount and size 

for the selected Ptes sample one peak corresponding to one selected size is seen in the histogram, the peak maximum at 1.1 nm fits the previous statistics 

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