Characterization of SNBCs by TEM. (a) Typical TEM image of SNBCs. (b) A magnified TEM image. (c) HRTEM image of SNBCs. (d) SAED pattern of SNBCs which were indexed according to (111), (200), (220), and (311) reflections of fcc silver on the basis of their d-spacings of 2.47 A0, 2.13A0, 1.49 A0, and 1.27 A0.