Electrodeposited bismuth telluride (Bi2Te3) nanowires using anodic alumina (AAO) templates show anisotropic thermal properties in a direction parallel and perpendicular to the nanowire/nanochannel axis. The present study reports thermal diffusivity measurement of templated Bi 2Te3 nanowires in a direction perpendicular to the nanowire axis, using an active infrared thermography based noncontact technique. Measurements were performed on empty AAO templates of varying pore dimensions, AAO/Bi2Te3 nanocomposites and a single crystal Bi 2Te3 sample. A first order lower bound model estimation showed nearly five-fold reduction of thermal conductivity in 200 nm Bi 2Te3 nanowires as compared to the bulk values. © 2013 Elsevier B.V.