Novel magnetic and optical properties of Sn1−xZnxO2 nanoparticles

In this work, we report on the effects of doping SnO2 nanoparticles with Zn2+ ions. A series of ∼2–3 nm sized Sn1−xZnxO2 crystallite samples with 0 ≤ x ≤ 0.18 were synthesized using a forced hydrolysis method. Increasing dopant concentration caused systematic changes in the crystallite size, oxidation state of Sn, visible emission, and band gap of SnO2 nanoparticles. X-ray Diffraction studies confirmed the SnO2 phase purity and the absence of any impurity phases. Magnetic measurements at room temperature showed a weak ferromagnetic behavior characterized by an open hysteresis loop. Their saturation magnetization Ms increases initially with increasing Zn concentrations; however for x > 0.06, Ms decreases. Samples with the highest Ms values (x = 0.06) were analyzed using an Inductively Coupled Plasma Mass Spectrometer, looking for traces of any magnetic elements in the samples. Concentrations of all transition metals (Fe, Co, Mn, Cr, and Ni) in these samples were below ppb level, suggesting that the observe...