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In this talk I will discuss our latest results toward realizing nanomaterial energy devices through chemical and structural engineering. I will discuss our work on chemical engineering surfaces of nanoparticles toward creating nano-dot solids that are conducting: we have developed a novel surface modification method to link colloidal nanoparticles together through inorganic bridges. Our method completely removes the bulky surfactant ligands from both II-VI and IV-VI semiconducting nanocrystal films using (NH4)2S. I’ll also discuss our chemical and structural engineering of cobalt nanoparticles to create additive-free battery electrodes – anodes made without polymeric binders or carbon black. We have found that electrophoretic deposition (EPD) of nanoparticles creates a strong enough electrical and mechanical bond for the nanoparticle batteries to perform at maximum capacity. Finally, I’ll discuss our new structural characterization tool, where we have developed a microfabricated phonon spectrometer. Non-thermal distributions of phonons are locally excited and detected in silicon micro- and nanostructures by decay of quasiparticles injected into an adjacent superconducting tunnel junction. In our prototype phonon spectrometer we have demonstrated spatial resolution of 200 nm, a frequency resolution of ~20 GHz, and a frequency range from ~80 to ~800 GHz. Our results on Si nanosheets indicate that the Casimir limit is reached at much lower frequencies than previously believed.