Nanocrystalline (RE2O3)x(SnO2)1−x (x = 0.02–0.15, RE = La, Sm, Gd, Ho, Yb, Y) powders were synthesized by a two-step hydrothermal process in the presence of urea, followed by the calcination between 400 and 1000 °C. The average crystallite size of the as-calcined samples decreased with the increase of dopant content, suggesting that doping an appropriate amount of RE into nanosized SnO2 could effectively inhibit the grain growth. Structure characterization revealed that (RE2O3)x(SnO2)1−x, except (Yb2O3)x(SnO2)1−x, appeared tetragonal SnO2 at low temperature, and segregated cubic RE2O3 upon calcination, and transformed into cubic RE2Sn2O7 over 800–1000 °C. The amount of the RE2Sn2O7 increased with the increase of RE dopant content. For (Yb2O3)x(SnO2)1−x (x = 0.02–0.15), only cassiterite SnO2 was observed at the high calcination temperature of 1000 °C, and the lattice parameter refinement revealed that both lattice parameter and lattice volume decreased linearly with the increase of Yb2O3 content.
The growing interest and activity in the field of sensor technologies requires a forum for rapid dissemination of important results: Sensor Letters is that forum. Sensor Letters offers scientists, engineers and medical experts timely, peer-reviewed research on sensor science and technology of the highest quality. Sensor Letters publish original rapid communications, full papers and timely state-of-the-art reviews encompassing the fundamental and applied research on sensor science and technology in all fields of science, engineering, and medicine. Highest priority will be given to short communications reporting important new scientific and technological findings.