Recently, the research on semiconductor photocatalytic materials has attracted worldwide interests because of their potential in solving global energy and environmental problems by effective utilization of solar energy. However, the photocatalytic activity of semiconductor photocatalysts should be further improved from the utilitarian and commercial viewpoints. Nanoscale and nanostructured photocatalytic materials with novel properties (e.g., enhanced light absorption, quantum confinement, high specific surface area and tunable surface-to-volume ratio, hierarchical porous structures, etc.) create tremendous opportunities in extending their applications in various fields such as water and air purification, photocatalytic disinfection, photocatalytic hydrogen generation, and dye-sensitized solar cells. A rapid growth of these applications indicates a need for the assessment of potential risk of nanomaterials to environment and organisms.

The recent advances in the area of nanosized photocatalytic materials inspired us to edit this special issue of Journal of Nanomaterials, which is devoted to their synthesis, characterization, properties, risk assessment, and applications. To achieve this purpose, we cordially invite investigators to contribute original research articles as well as review articles that will stimulate further activities in this area and improve our understanding of the key scientific problems in nanosized photocatalytic materials. We are particularly interested in articles describing the new methods for the synthesis of nanosized photocatalytic materials with novel morphology, exposed active facets, and nanoporous structures, which may greatly benefit their photocatalytic performance. Potential topics include, but are not limited to:

• Synthesis, surface modification, and recent developments in nanosized photocatalytic materials
• Synthesis of nanostructured and nanoporous photocatalytic materials with novel morphology
• Characterization of nanosized photocatalytic materials
• Electronic properties and photochemistry of nanosized photocatalytic materials
• Nanosized photocatalytic materials for hydrogen production, solar cells, environmental applications, disinfection, and so on
• The bioeffects, biosafety, and potential toxicity of nanosized photocatalytic materials

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/ according to the following timetable: