With depleting fossil fuels and growing concern about environmental protection, urgent research efforts are needed to find alternative energy resources that are efficient, economical, and ecologically friendly. Since energy resources such as solar power are intermittent but the usage is increasing in numerous portable electronic devices, efficient means have to be found for energy storage and transportation. A number of devices have been proposed for this purpose, for example, photovoltaic solar cells, batteries, and supercapacitors.

The main purpose of this special issue is to develop functional nanomaterials and nanotechnologies for efficient energy conversion and storage. Along with this direction, three types of nanomaterials have been mostly explored: (1) metal and metal oxide with different morphologies; (2) new carbon materials such as graphene, carbon nanotube, and C60 derivatives; (3) conducting polymers. The submissions on development of these nanomaterials for energy devices are particularly welcome. Of course, the other nanomaterials will be also encouraged. This special issue will focus on (1) preparation, characterization, functionalization, and properties of nanoparticles, films, nanoporous materials, and nanocomposites; (2) optimization of conversion and storage devices based on nanomaterials. The fundamental understanding of the mechanism on materials and processes at nanoscale will be highlighted. Potential topics include, but are not limited to:

• Flexible lithium ion batteries and supercapacitors
• Nanomaterials for energy storage
• Printable energy and electronic devices
• Nanowire mesh as transparent electrodes
• Optoelectronic macromolecules
• Thin film solar cell device research
• Novel nanomaterials for light emitting diodes
• Structure and interface of photoelectric materials and devices

Before submission authors should carefully read over the journal's Author Guidelines, which are located at http://www.hindawi.com/journals/jnm/guidelines/. Prospective authors should submit an electronic copy of their complete manuscript through the journal Manuscript Tracking System at http://mts.hindawi.com/submit/journals/jnm/fnoc14/ according to the following timetable: