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Phosphorus-doped ZnO nanostructures are synthesized on porous alumina membranes by evaporating the mixture of pure Zn, carbon, and P2O5 powder. The influences of growth area on phosphorus-doped ZnO nanostructures are studied in detail. The Raman spectra indicate that phosphorus enters into the ZnO crystal lattice to easily form a Zn–P bond and/or a PZn–O one by occupying an O site and a Zn one. The further analyses for Raman spectra and SEM results display that the change of nanorods morphology should mainly be attributed to the relaxation of lattice strain caused by P occupying Zn sites. Compared with the morphology of samples on Si substrate, it is found that alumina membranes are helpful to the growth of nanostructures due to the existence of localized negative charges. The growth mechanism of different nanostructures is also discussed. The present research results are helpful to realize the preparation of phosphorus-doped ZnO nanostructures with controllable morphologies.

Magnetic critical behavior of Mn5Ge3 ribbons was investigated by dc magnetization measurements. The critical exponents were obtained by a modified Arrott plot technique and the Kouvel–Fisher method. Finally, β = 0.372 ± 0.003 and γ = 1.05 ± 0.01 were determined. The exponent δ = 3.88 ± 0.02 obtained from the magnetization isotherm of TC fulfills the Widom scaling relation δ = 1 + γ/β. Moreover, with these exponents, the magnetization curves collapse into two independent curves following a single equation around TC. These results confirm the reliability of the obtained critical exponents. However, this set of exponents belongs to none of the classical theoretical models. This phenomenon is probably caused by the anisotropy of the Mn ions.

Electron paramagnetic resonance studies have been performed on the perovskite manganite Pr0.55Sr0.45MnO3. The various spectrum parameters including line width, effective g-value and double-integrated intensities have been analyzed in detail. The changes of g-value and linewidth are indicative of the presence of strong spin–lattice interaction in the paramagnetic regime. The lattice distortion causes the appearance of localized carriers and the formation of a small polaron. Therefore, the large activation energy obtained from two different methods implies that a strong spin–lattice correlation exists in Pr0.55Sr0.45MnO3.