The influence of nickel dopant on the microstructure and optical properties of SnO₂ nano-powders

The microstructure and optical properties of Ni-doped SnO₂ nano-powders are studied in detail. By Ni-doping, not only the grain size reduces, but also the grain shape changes from nano-rods to spherical particles. The crystallization becomes better with annealing temperature increasing. The band gap energy decreases as nickel doping level increases. The sp--d hybridization and alloying effect due to amorphous SnO_2-x phase should be responsible for the band gap narrowing effect. Nickel dopant does not change the photoluminescence (PL) peak positions.