Journal: ACS Omega

Article Title: Probing Light-Matter Interactions: Fluorescence Lifetime Manipulation in a Crystalline Colloidal Array

doi: 10.1021/acsomega.4c07335

Figure Lengend Snippet: Nanophotonic manipulation of the photoluminescence of NMMA-copolymerized nanoparticles in an ordered array. Photoluminescence excitation (PLE) (blue) and photoluminescence (PL) (red) spectra of (a) free NMMA dye in toluene (1 μg/mL) and (b) NMMA-copolymerized nanoparticles in deionized water at a dilute concentration, where no rejection wavelength (λ rw ) exists in the visible regime (9.55 × 10 11 particles/mL, 1.17 mg/mL). The emission (λ em ) and excitation (λ ex ) wavelengths utilized for PLE and PL measurements, respectively, are indicated in (a,b). Excited-state lifetimes were monitored incrementally across the PL spectra of the free NMMA dye and nanoparticles. Decay profiles were collected to a peak count condition of 10,000 (P 10K ) and fit to a single or double exponential decay function, yielding one (red circles) or two (red squares) lifetimes, respectively. (c) PL spectra of the ordered array (OA) composed of NMMA-copolymerized nanoparticles with the position of λ rw denoted by a red arrow. PL spectra of the OA (red) and its corresponding disordered array (DA, blue) when the λ rw was at (d) 493 nm and (e) 543 nm, and (f) 583 nm. Difference in PL spectra (ΔPL) of the OA (red) compared to the DA (blue) when the λ rw was at (g) 493 nm, (h) 543 nm, and (i) 583 nm. The reflectance (λ rw ) of OA is presented in (g–i). Photographs of a liquid droplet of NMMA-copolymerized nanoparticles exposed to (j) white light and (k) ultraviolet (UV) light. The λ rw value of the droplet is indicated.

Article Snippet: Briefly, 0.5 mL of the aqueous dispersion of poly(propargyl acrylate) colloidal nanoparticles were dispersed in 1 mL DI water and 2 mL tetrahydrofuran (THF) in a J-KEM mini reactor tube equipped with a stir bar.

Techniques: Concentration Assay

Journal: ACS Omega

Article Title: Probing Light-Matter Interactions: Fluorescence Lifetime Manipulation in a Crystalline Colloidal Array

doi: 10.1021/acsomega.4c07335

Figure Lengend Snippet: Nanophotonic manipulation of the decay kinetics of NMMA-copolymerized nanoparticles in an ordered array. (a–d) Photoluminescence (PL) spectra of the ordered array (OA, red) composed of NMMA-embedded colloidal nanoparticles with the rejection wavelength at 486, 536, 590, and 645 nm, respectively, and corresponding disordered reference array (DA, blue) at the equivalent particle densities. The λ rw is denoted by a red arrow. The inset of (d) presents the PL spectra on a log scale. (e–h) Average (at least n = 3) measured excited-state lifetimes (τ 1 ) of OA collected to a decay profile peak count condition of 500 counts (P 500 ) (red crossbars) and 10,000 counts (P 10K ) (red circles) and DA at equivalent particle densities collected to P 500 (blue crossbars) and P 10K (blue circles). The minimum and maximum observed lifetimes at each wavelength are also presented. (i–l) Percent change in the average measured lifetime (Δτ 1 ) collected to P 500 of OA in reference to DA when the stop-band was at 486, 536, 590, and 645 nm, respectively. (m–p) Δτ 1 collected to P 10K of OA compared to DA when the stop-band was at 486, 536, 585, and 642 nm, respectively.

Article Snippet: Briefly, 0.5 mL of the aqueous dispersion of poly(propargyl acrylate) colloidal nanoparticles were dispersed in 1 mL DI water and 2 mL tetrahydrofuran (THF) in a J-KEM mini reactor tube equipped with a stir bar.

Techniques:

Journal: ACS Omega

Article Title: Probing Light-Matter Interactions: Fluorescence Lifetime Manipulation in a Crystalline Colloidal Array

doi: 10.1021/acsomega.4c07335

Figure Lengend Snippet: Multiexponential fits of decay profiles exhibiting the nanophotonic manipulation of the decay kinetics of NMMA-copolymerized nanoparticles in an ordered array. Multiexponential fits of decay profiles (at least n = 3) of the NMMA-copolymerized nanoparticles in an ordered array (OA) and disordered “reference” array (DA) when the rejection wavelength (λ rw ) of the OA was at (a–c) 486 nm, (d–f) 536 nm, (g–i) 585 nm, and (j–l) 642 nm. The wavelength at which each decay profile was monitored is indicated in the top right of each panel, and a 2 nm bandpass was used for all measurements. Decay profiles were collected to a peak count condition of 10,000 (P 10K ) and best fit with a double or triple exponential decay function (cf. Supporting Information , Figures S12–S15 and Tables S7–S10 for decay profiles and further details).

Article Snippet: Briefly, 0.5 mL of the aqueous dispersion of poly(propargyl acrylate) colloidal nanoparticles were dispersed in 1 mL DI water and 2 mL tetrahydrofuran (THF) in a J-KEM mini reactor tube equipped with a stir bar.

Techniques: