Extended Data Fig. 8: The energy transfer process in the core-shell α-NaYF4:X@Na3CrF6(X = 5 mol% Nd, 3 mol% Yb, 5 mol% Er, and 3 mol% Tm)@Na3CrF6 NPs.
From: High-brightness transition metal-sensitized lanthanide near-infrared luminescent nanoparticles
a-d, TRPL spectrum of α-NaYF4:Nd(5 mol%)@Na3CrF6 (a), α-NaYF4:Yb(3 mol%)@Na3CrF6 (b), α-NaYF4:Er(5 mol%)@Na3CrF6 (c) and α-NaYF4:Tm(3 mol%)@Na3CrF6 (d) under 655 nm laser excitation. e-h, TRPL kinetics analysis of α-NaYF4:Nd(5 mol%)@Na3CrF6 (e) at four characteristic emission peaks (778 nm, 868 nm, 1,048 nm and 1,318 nm), α-NaYF4:Yb(3 mol%)@Na3CrF6 (f) at two characteristic emission peaks (774 nm and 974 nm), α-NaYF4:Er(5 mol%)@Na3CrF6 (g) at three characteristic emission peaks (778 nm, 978 nm and 1,532 nm) and α-NaYF4:Tm(3 mol%)@Na3CrF6 (h) at three characteristic emission peaks (778 nm, 1,438 nm and 1,622 nm). i-l, TRPL spectra at different time delays of α-NaYF4:Nd(5 mol%)@Na3CrF6 (i) from 0.1425 to 0.56 ms, α-NaYF4:Yb(3 mol%)@Na3CrF6 (j) from 0.07 to 0.25 ms, α-NaYF4:Er(5 mol%)@Na3CrF6 (k) from 0.145 to 0.485 ms and α-NaYF4:Tm(3 mol%)@Na3CrF6 (l) from 0.1325 to 0.75 ms. m-p, Schematic of energy transfer process from Cr3+ to Nd3+ (m) in α-NaYF4:Nd(5 mol%)@Na3CrF6, Cr3+ to Yb3+ (n) in α-NaYF4:Yb(3 mol%)@Na3CrF6, Cr3+ to Er3+ (o) in α-NaYF4:Er(5 mol%)@Na3CrF6, and Cr3+ to Tm3+ (p) in α-NaYF4:Tm(3 mol%)@Na3CrF6.
