Infiltrated Zinc Oxide in Poly(methyl methacrylate): An Atomic Cycle Growth Study

Abstract

We have investigated the growth of zinc oxide in a polymer matrix by sequential infiltration synthesis (SiS). The atomic cycle-by-cycle self-terminating reaction growth investigation was done using photoluminescence (PL), Raman, and X-ray photoemission spectroscopy (XPS). Results show clear differences between Zn atom configurations at the initial stages of growth. Mono Zn atoms (O–Zn and O–Zn–O) exhibit pure UV emission with little evidence of deep level oxygen vacancy states (VO). Dimer Zn atoms (O–Zn–O–Zn and O–Zn–O–Zn–O) show strong UV and visible PL emission from VO states 20 times greater than that from the mono Zn atom configuration. After three precursor cycles, the PL emission intensity drops significantly exhibiting first evidence of crystal formation as observed with Raman spectroscopy via the presence of longitudinal optical phonons. We also report a first confirmation of energy transfer between polymer and ZnO where the polymer absorbs light at 241 nm and emits at 360 nm, which coincides with...