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We present a method for characterizing ultrasmall (<2 nm) supported crystallites with benchtop XRD. Central to the method is an understanding of the intensity effects at play; these intensity effects and their corrections are discussed in depth. Background subtraction�long considered one of the main barriers to ultrasmall crystal characterization�is solved by correcting the diffractogram of a separately measured support for the relevant intensity effects. Rietveld refinement is demonstrated to be an adequate analysis method for the general characterization of simple nanosystems. A 4.8% Pt/SiO 2 sample (1.3 nm, volume-weighted average) is used as a case study; it is found that the Pt spontaneously oxidizes under ambient conditions and consists of a metallic core surrounded by a PtO 2 shell. Both phases have average dimensions smaller than 1 nm. The XRD results also suggest lattice expansion of the Pt core as compared to bulk Pt.

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The conductivity and strength of carbon nanotube (CNT) wires currently rival those of existing engineering materials; fullerene-based materials have not progressed similarly, despite their exciting transport properties such as superconductivity. This communication reveals a new mechanically robust wire of mutually aligned fullerene supramolecules self-assembled between CNT bundles, where the fullerene supramolecular internal crystal structure and outer surface are aligned and dispersed with the CNT bundles. The crystallinity, crystal dimensions, and other structural features of the fullerene supramolecular network are impacted by a number of important production processes such as fullerene concentration and postprocess annealing. The crystal spacing of the CNTs and fullerenes is not altered, suggesting that they are not exerting significant internal pressure on each other. In low concentrations, the addition of networked fullerenes makes the CNT wire mechanically stronger. More importantly, novel mutually aligned and networked fullerene supramolecules are now in a bulk self-supporting architecture.