Nano-objects in dry and liquid conditions have shown reductions in friction and wear on the macroscale. In this research, for the first time, carbon nanohorn (CNH) nanoparticles were studied on the nanoscale under dry and low viscosity liquid environments for their effect on friction and wear reduction. The data were compared with gold (Au) nanoparticles and molybdenum disulfide (MoS2) and tungsten disulfide (WS2) nanotubes. Atomic force microscopy (AFM) experiments on the nanoscale were performed in single-nano-object contact with an AFM tip, where nano-objects were laterally manipulated and multiple-nano-object contact with a tip attached to a glass sphere sliding over several nano-objects. Wear tests were performed on the nanoscale with an AFM as well as on the macroscale by using a ball-on-flat tribometer to relate friction and wear reduction on both scales. Results indicate CNH nanoparticles contribute to friction and wear reduction due to the reduced contact area and low meniscus force contribution. (C) 2013 Elsevier Inc. All rights reserved.