Photocatalyst Nanomaterials for Environmental Challenges and Opportunities

Youngmi Koo1,Boyce Collins1,Jagannathan Sankar1, and Yeoheung Yun1*

Engineering Research Center, North Carolina A & T State University,Greensboro, NC, USA.

*Corresponding Author

Yeoheung Yun
Engineering Research Center,
North Carolina A & T State University,
Greensboro, NC, USA.
E-Mail: yyun@ncat.edu & force9488@gmail.com

Article Type: Editorial
Received: October 11, 2012; Published: November 20, 2012;

Citation: Koo Y, Collins B, Sankar J, Yun Y (2012) Photocatalyst Nanomaterials for Environmental Challenges and Opportunities, Int J Nano Stud Technol, 1(2e), 1-2. doi: dx.doi.org/10.19070/2167-8685-120002e

Copyright: Yun Y© 2012. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution and reproduction in any medium, provided the original author and source are credited.

Climate change caused by fossil-fuel use and other natural causes as well as Western and Asian economic growth driven by excessive consumption is among the biggest environmental challenges of the 21st century. Advances in nanotechnology bring a new tool set to remediate environmental challenges such as pollutant removal, antiterror, air/liquid/soil filtration, and carbon dioxide conversion to hydrocarbons. As innovative engineered nanomaterials emerge, it is critical to establish the fundamental science of these new materials so that their utility is optimized and un-intended consequences of their use are avoided.

The potential of photoelectrocatalyst nanomaterials is significant for environmental clean-up, pollution control, chemical/biological weapon remediation, emission filtration, and carbon diox-ide conversion. In principle, catalyzed reactions energized by natural sunlight can be used to clean water, remove toxic chemicals, and create fuel and synthon stock and can be achieved using titanium dioxide particle systems [1]. Photoactive properties of titanium dioxide particles such as super-hydrophilicity, self-cleaning, and antibacterial qualities, were enhanced by doping with novel metals (Pt, Pd, Au, Ag, Cu, or Ni) and carbon nanomaterials (carbon nanotubes, graphene)[2-8]. Further tailoring of TiO2 nanoparticle systems is under development to be used for air and wa -ter pollution removal for industrial and defense purposes. Even though photocatalytic reaction of TiO2 was developed in the early 1970’s [9], nanoscaled applications of the materials is improving catalytic efficiency and allowing smarter functionalities through chemical and physical alteration.

A potential promise of TiO2 nanoparticles science is the catalytic conversion of carbon dioxide into useful hydrocarbons driven by sunlight energy. Carbon dioxide is a thermodynamically stable molecule and a significant amount of energy is required for catalytic reaction; however photocatalyst utilizing TiO2 nanoparticles have been shown to convert CO2 and water vapor into hydrocarbon fuels using sunlight [10]. Modification of TiO2 nanoparticles by doping with metals can tune bandgap properties and decrease exciton recombination rates, which eventually increase the availability of electron and holes for chemical conversion of substrates (CO2 and H2O, for example) and increases visible light sensitivity which allows for more efficient harvesting of the solar spectrum. Other nanoparticle systems can be assembled with the TiO2 particles to tune and improve catalytic efficiency. Carbon nanomaterials are such a promising material due to their light absorption properties, electron storage capabilities, and electronic behavior, tunable from metallic to semiconductor. Additionally smart TiO2 systems can be developed into sensors such as antiterrorism and bioweapon neutralization due to their chemical and electrical properties. As Dr. Richard Feynman said, “there’splenty of room at the bottom”[11]; we envision there is still a lot of room for TiO2 nanotechnology to innovate positively for human and earthly welfare.

In conclusion, new photocatalyst nanomaterials like TiO2 coupled with metals, functional polymers, and carbon nanomaterials are targeted to yield smart materials that exhibit outstanding photocatalytic reactivity under sunlight, biological and chemical inertness, nontoxicity, long-term stability, and that can be interfaced with electronic and photonic sys -tems. As this science develops, the sustainability of such materials and their net impact on global health will be a focus of the fields of engineering and science. Optimally, the application of these smart ma -terials can mitigate the deterioration of our natural environment and improve clean air, potable water, and wastewater treatment through the removal of toxic pollutants. Further applications include the inactivation of organisms such as bacteria, viruses, and cancer. The impact of efficient, sustainable photocatalytic particles has many useful and practical applications that could ultimately result in a simpler, more efficient, and equitable economic systems.

Acknowledgement

This research was partially supported by BAA11-001 Long Range Board Agency for Navy and Marine Corps Science and Technology Program.

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