We report on the observations of enhanced superconductivity in a very loosely packed 6.8 nm Al nanoparticle assembly and the suppression of superconductivity by interparticle interactions, through ac magnetic susceptibility and magnetization measurements. T(C) and H(C) of the 6.8 nm Al particles are, respectively, 1.9 and 77 times higher than that of bulk Al. M(H(a)) curves taken below and above T(C) can all be described by a Langevin profile, showing the existence of a spontaneous magnetic component in superconducting phase. Superconductivity is found to be gradually suppressed by interparticle interactions. (C) 2011 American Institute of Physics. [doi:10.1063/1.3564936]
