Fig. 1: Characterizations of water-insensitive nanoparticles (WINPs). | Light: Science & Applications

Fig. 1: Characterizations of water-insensitive nanoparticles (WINPs).

From: Water-insensitive NIR-I-to-NIR-I down-shifting nanoparticles enable stable biomarker detection at low power thresholds in opaque aqueous environments

Fig. 1

a TEM images of WINPs (top left), high-resolution TEM image (top right), and corresponding Fourier transform diffraction pattern (inset). Size distribution histogram (bottom left) and X-ray diffraction (XRD) patterns (bottom right). b Schematic illustration of the NIR-I-to-NIR-I down-shifting process in WINPs under 800 nm excitation. c NIR-I emission spectrum of NaYF4:x%Nd@NaYF4 (x: 0.5–90 mol%) under c.w. 800 nm excitation with a power density of 0.1 W cm−2. d Time-dependent emission profiles of NaYF4:x %Nd@NaYF4 (x: 0.5–90 mol%) at the transition of 4F3/2 → 4I9/2 under 1 ms pulsed laser excitation. e Characterizations of as-synthesized nanoparticles; (top) absorption coefficient of NaYF4:x%Nd@NaYF4 at around 800 nm wavelength, (middle) lifetime decay time, and (bottom) NIR emission intensities as a function of Nd3+ concentrations (0.5–90 mol%). (a.u. arbitrary units)

Back to article page