Shaping Luminescent Properties of Yb3+ and Ho3+ Co-Doped Upconverting Core-Shell β-NaYF4 Nanoparticles by Dopant Distribution and Spacing.

Shaping Luminescent Properties of Yb3+ and Ho3+ Co-Doped Upconverting Core-Shell β-NaYF4 Nanoparticles by Dopant Distribution and Spacing.