4 Fabricating Nanostructures via Organic Molecular Templates Yunshen Zhou and Bing Wang 4.1 Introduction In the rapid growth of nanoscience and technology, organic compounds occupy a prominent position and play comprehensive roles as stabilizers [1–5], protective masks [6], templates [7–9], surface modifiers [10], position indicators [11], functional units and building blocks [12–17], and molecular “ink” [18–21], etc. Further more, organic compounds are key components in the design and fabrication of nanomachines and nanodevices. Utilization of organic molecules has allowed prototypes of nanomachines and nanodevices, such as molecular motors [22–26], conductors [27–30], logic gates [31], memories [32], rectifiers [33–36], negative differential resistance devices [37], single electron tunneling devices [38], and gears [39–41], to be developed [42]. Using organic compounds as templates to transfer the desirable and controllable patterned structures into mechanically and chemically stable, durable, and processable nanostructures has received tremendous attention for decades [43–47]. In general, template materials require some characteris- tics [48]: 1. Have featured structures for the final materials 2. Be stiff and durable enough to maintain their structures during the templating processes 3. Be easily removed without disrupting the final materials, if the final materials do not require the templates Templating nanostructures includes several steps: firstly, organic tem- plates with featured structures are fabricated by advanced techniques; sec- ondly, the organic templates are brought into contact with precursors or preformed building units (the procedure generally occurs in solution, but can also occur in the gas phase), then the template-directed formation of nanos- tructures results in hybrid structural materials; finally, the organic templates may be removed if necessary by heat treatment [49], or washed with organic solvents [50] to produce the isolated structural materials. Easy removal of organic templates is one of the advantages of using organic templates instead of inorganic templates [51, 52]. Organic templates include any templates consisting of organic species [53]. Organic molecular templates, polymer templates, carbon nanotubes, and