Determination of the microstructure of Eu-treated ZnO nanowires by x-ray absorption

摘要

X-ray absorption near-edge structure u0001XANESu0002, extended x-ray absorption fine structures u0001EXAFSu0002,nand photoluminescence measurements were used to elucidate the microstructural andnphotoluminescence properties of ZnO nanowires u0001ZnO-NWsu0002 that had been treated with Eu bynthermal diffusion. The O K- and Eu L3-edge XANES and EXAFS spectra at the Zn K- andnEu L3-edge verified the formation of Eu2O3-like layer on the surface of ZnO-NWs. X-rayndiffraction, XANES and EXAFS measurements consistently suggest the lack of substitutionalndoping of Eu ions at the Zn ion sites in the interior of ZnO-NWs. The clear sharp and intensenemission bands in the range 610–630 nm of Eu-treated ZnO-NWs originated from the intra-4fntransition of Eu ions in the Eu2O3-like surface layer.