EDUCATION
Ph.D. Environmental Science and Engineering University of Texas at El Paso, 2003.
Masters in Analytical Chemistry University of Texas at El Paso, 2000.
Bachelors Environmental Science (Chemistry), Memorial University of Newfoundland, 1998.
PROFESSIONAL EXPERIENCE
Assistant Professor University of Texas Pan American, Edinburg TX (2009-present),
Research Specialist, Department of Chemistry, University of Texas at El Paso, El Paso TX (2003-2009)
Part-time Instructor, El Paso Community College, El Paso TX (2007- 2009),
Research Assistant, Department of Chemistry, University of Texas at El Paso, El Paso TX (2000-2003)
Selected Publications
Appl. Spectros. (2009), 63, 961-970.
J. Phys. Chem. Solids (2009), 70, 555-560.
Plant Physiol. Biochem. (2009), 47, 608-614.
Nanotechnol. (2009), 20, 105607/1-105607/8
Inorg. Chim. Acta, (2009), 362, 395-401
Intern. J. Phytoremediation (2009), 11, 131-149.
Phytochem. (2009), 70, 540-545.
Microchem. J. (2009), 91, 100-106.
Environ. Chem. (2008), 5, 320-331.
Intern. J. Environ. Poll. (2008), 34, 28-42.
Chemosphere (2008), 70, 2076-2083.
Environ. Sci. Technol. (2007), 41, 8165-8170.
J. Mat. Res. (2007), 22, 2747-2757.
Chem. Comm. (2007), 28, 2944-2946.
Book Chapters
Biological and biomaterials-assisted synthesis of precious metal nanoparticles. In: Kumar, C. S.S.R. (ed.), Metallic and Metal oxide nanomaterials (nanomaterials for life science Vol. 1), Wiley-VCH, Verlag, GmbH, KGaA, Weinheim, (2009) pp. 461-491.
Production of metal nanoparticles by plants and plant-derived materials. In: Corain, B., Schmid, G Toshima, N. (eds.), Metal nanoclusters in catalysis and materials sciences: the issue of size-control. Elsevier Publishing (2008). 401-411
Algal Biotechnology Applications for the Removal of Heavy Metals. Book Chapter Singh, S. (ed.) Micro-algal Biotechnology, Rani Durgavati University, Jabalpur, India (2007), (Accepted for publication).
Use of plants in biotechnology: synthesis of metal nanoparticles by inactivated plant tissues, plant extracts, and living plants. Developments in Environmental Science 5 (Concepts and Applications in Environmental Geochemistry), (2007) 463-485.
RESEARCH INTERESTS:
I have varied research interests which include the broadly defined category of environmental chemistry which can encompass inorganic/bio-inorganic, nanomaterials, and analytical chemistry. More specifically, my research interests are in the interactions of heavy metal/semimetal ions/complexes and nanomaterials with biological systems such as microorganisms and plants. In addition, I am also interested in the analytical chemistry of nanomaterials and the reactions of these materials. The synthesis, characterization and applications of nanomaterials to different environmental problems and the possible environmental problems associated with these types of materials are my research interests as well. In addition, I am interested in the applications of different analytic instrumentation, such as ICP-OES, ICP-MS, LC-ICP-MS, synchrotron based X-ray Absorption spectroscopy (XAS including EXAFS and XANES), FTIR, and XRD to the analysis of environmental samples.
1.) Environmental Chemistry:
The uptake of metals and semimetals by biological systems including plants species is documented in the literature. It has been shown that most metal and semimetal ions are taken up by plants and algae and multiple effects are visible in the different biological system. In addition, it has also been shown that the uptake of specific metal ions can result in the formation of nanomaterials. For example, gold and silver ions can form nanoparticles within plant biomasses. Others have reported that other metals and semimetals go through bio-reduction or bio-transformation processes once inside or in contact with the biological system. Elements such as chromium(VI) have been shown to reduce to chromium(III), arsenic(V) oxide has been reported to be reduced and complexed through thiol ligands; while arsenic(III) oxides are bio-converted to arsenic(III) thiol complexes. Similarly, cadmium ions have been shown to be complexed to thiol containing ligands. However, the interactions of metals and semimetal ions with plant species are dependent not only on the plant species but also on the speciation and the type of complex of the element introduced to the biological system.
2.) Fuels/Energy Research
In this field or research I am interested in the ability to stretch out the current fuel supplies to meet our current and future demands. This goal can be achieved through the development of technologies that make non-desirable, which are oil supplies that contain a high concentration of S useful though cost effective methods. My interests in this area of fuels research lie in the development of technologies oxidative for desulfurization of sour crudes (heavy feeds). The model reaction for OSD is shown below:
We have shown that platinum, gold, and silver nanoparticles are catalytic in the oxidation of dibenzothiophene to the dibenzothiophene sulfone molecule. Currently we are looking for new molecules and nanomaterials/ supports for this reaction.
Furthermore, I am interested in the origins of crude oil contrary to popular belief the origins of crude oil are not fully understood. In terms of fuel research it is my belief that in order to find a suitable organism for the synthesis of biodiesel first it is necessary to understand the origins of crude oils. From discovery of the organism/organisms that made the current petroleum reserves a model organism from current living organisms may be available to attempt to synthesize crude oils. These reactions may be feasible under the proper physical and chemical conditions to synthesize crude oils, which would remove the mystery around the origins of crude oil and provide a viable source of crude oil and energy independence for the country.
3.) Nanomaterials Synthesis and Application:
One final research area I am interested in is in the synthesis, characterization, and applications of engineered nanomaterials. The applications of engineered nanomaterials are numerous and include but are not limited to catalysis, optical devices, electronics, sensors, environmental remediation, medical, and the list is continually growing. In terms of synthesis there are two major routes, which include classical synthesis and green synthesis. The classical synthetic routes are well defined in the literature. However, newer environmentally conscious synthetic routes are being developed every day. The green synthesis techniques are generally synthetic routes that utilize relatively non-toxic chemicals to synthesize nanomaterials, and include the use of non-toxic solvents (such as water), biological extracts, biological systems, and microwave assisted synthesis. The nanoparticles can then be characterized and compared to conventionally synthesized nanoparticles for size, shape, and reactivity for any changes in the activity or properties of the nanoparticles.
