ABSTRACT
The bulk-scale synthesized powders of nanowires (NWs) exhibit distinct colors. The undoped NWs are pale yellow; p-doped NWs are deeper yellow; while the n-doped NWs are dark blue. This may simply reflect the higher carrier concentration in n-doped systems. Tin oxide doping was also investigated through studies of surface plasmons as it provides a convenient means of determining the carrier concentration by contact-free measurement. The chapter presents synthetic methods for synthesizing doped NWs for tin oxide and illustrates their application in gas sensing. Replacing n-doped NPs with n-doped nanowires should lead to a faster response by reducing the number of interparticle electron hops between the sensing electrodes. The first synthesis of single crystalline n-doped and p-doped SnO2 NWs is reported. The availability of both n- and p-type NWs opens up new opportunities for crafting transparent nanoelectronic devices, sensors, and so on.
