Environmental Chemical Physics Laboratory

Physical Models for Environmental Chemistry

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We develop physical models, through theoretical and experimental studies, to quantify chemical equilibrium and kinetics in adsorption, ion exchange, catalysis, desalination, and microbiology. The goal is to link macroscopic observations with molecular mechanisms. We are located in the Maddox Engineering Research Center at Texas Tech University. Contact: Chongzheng Na, (806) 834-3597, chongzheng.na@ttu.edu.

Capillary Theory of Adsorption

Adsorption of compounds dissolved in solution by solids is often mistaken as being equivalent to the adsorption of gases even though the two processes show distinctively different behaviors. New models are desparately needed to account for the capillary effect of surface tension in solution-phase adsorption. Similar needs exist for understanding solution-phase ion exchange.

Size Dependence of Catalysis

The kinetics of heterogeneous catalysis shows an abnormal dependence on nanoparticle size, in which the reaction rate can either increase or decrease with the increase of size depending on the temperature. New models are needed to explain the interwined dependence of catalysis on size and temperature.

Multibody Coalescence of Droplets

The number of particle-stabilized droplets involved in coalscence equals four times the tetrahedral number sequence although coalescence is often believed to only occur pairwise according to the von Smoluchowski theory of coagulation. New models are needed to understand the unique interaction among particle-stabilized droplets.

Publicatons (33 journal articles, 1 book chapter, 1 patent)

  1. Na, C.; Xu, J. Freundlich interpretation of pH control and ion specificity in zeolite cation exchange. SN Applied Sciences, 2020, 2: 1389. Open Access.
  2. Na, C. Size-controlled capacity and isocapacity concentration in Freundlich adsorption. ACS Omega 2020, 5, 22, 13130–13135. Open Access.
  3. Honarparvar, S.; Zhang, X.; Chen, T.; Na, C.; and Reible, D. Modeling technologies for desalination of brackish water — Toward a sustainable water supplyCurr. Opin. Chem. Eng. 201926, 104-111. pdf.
  4. Showalter, A. R.; Duster, T. A.; Szymanowski, J. E. S.; Na, C.; Fein, J. B.; Bunker, B. A. An X-ray absorption fine structure spectroscopy study of metal sorption to graphene oxide. J. Colloid Interface Sci. 2017, 508, 75-86. pdf. supplementary material.
  5. Duster, T. A.; Na, C.; Bolster, D.; Fein, J. B. Transport of single-layered graphene oxide nanosheets through quartz and iron oxide-coated sand columns. J. Environ. Eng. 2016, 04016079. pdf. supplimentary data.
  6. Ma, H.; Wang, H.; Burns, P. C.; McNamara, B. K.; Buck, E. C.; Na, C.Synthesis and preservation of graphene-supported uranium dioxide nanocrystals. J. Nucl. Mater. 2016, 475, 113-122. pdf. supplementary material.
  7. Ma, H.; Wang, H.; Wu, T.; Na, C. Highly active layered double hydroxide-derived cobalt nano-catalysts for p-nitrophenol reduction. Appl. Catal. B 2016, 180, 471-479. pdf. supplementary material.
  8. Wang, H.; Na, C. Chemical bath deposition of aluminum oxide buffer on curved surfaces for growing aligned carbon nanotube arrays. Langmuir. 2015, 31, 7401-7409. pdf. supporting information.
  9. Wang, H.; Grant, D. J.; Burns, P. C; Na, C. Infrared signature of the cation-π interaction between calcite and aromatic hydrocarbons. Langmuir. 2015, 31, 5820-5826. pdf. supporting information.
  10. Krylova, G.; Na, C. Photoinduced crystallization and activation of amorphous titanium dioxide. J. Phys Chem. C. 2015, 119, 12400-12407. pdf. supporting information.
  11. Na, C.; Tang, Y.; Wang, H.; Martin, S. T. Opposing effects of humidity on rhodochrosite surface oxidation. Langmuir. 2015, 31, 2366-2371. pdf. supporting information.
  12. Ma, H.; Na, C. Isokinetic temperature and size-controlled activation of ruthenium-catalyzed ammonia borane hydrolysis. ACS Catal. 2015, 5, 1726-1735. pdf. supporting information.
  13. Wu, T.; Wang, H.; Jing, B.; Liu, F.; Burns, P. C.; Na, C. Multi-body coalescence in Pickering emulsions. Nat. Commun. 2015, doi:10.1038/ ncomms6929. pdf. supplementary information.
  14. Ma, H.; Wang, H.; Na, C. Microwave-assisted optimization of platinum-nickel nanoalloys for catalytic water treatment. Appl. Catal. B 2015, 163, 198-204. pdf. supplementary material. Featured by Nanowerk and in Elsevier's catalysis journals brochure.
  15. Duster, T. C.; Szymanowski, J. E. S.; Na, C.; Showalter, A. R.; Bunker, B. A.; Fein, J. B. Surface complexation modeling of proton and metal sorption onto graphene oxide. Colloids Surf. A 2015, 466, 28-39. pdf.
  16. Wang, H.; Na, C. Binder-free carbon nanotube electrode for electrochemical removal of chromium. ACS Appl. Mater. Interfaces 2014, 6, 20309-20316. pdf. supporting information.
  17. Wang, H.; Na, C. Synthesis of millimeter-long vertically aligned carbon nanotube arrays on aluminum oxide buffer prepared by layer-by-layer assembly of boehmite nanoplates. Carbon 2014, 66, 727-729. pdf. supplementary materials.
  18. Jing, B.; Wang, H.; Lin, K.; McGinn, P. J.; Na, C.; Zhu, Y. A facile method to functionalize engineering solid membrane supports for rapid and efficient oil-water separation. Polymer 2013, 54, 5771-5778. pdf
  19. Wang, H.; Dong, Z.; Na, C. Hierarchical carbon nanotube membrane supported gold nanoparticles for rapid catalytic reduction of p-nitrophenol. ACS Sustain. Chem. Eng. 2013, 1, 746-752. pdf. supporting information. Featured in front cover.
  20. Wang, H.; Lin, K.; Jing, B.; Krylova, G.; Sigmon, G. E.; McGinn, P. J.; Zhu, Y.; Na, C. Removal of oil droplets from contaminated water using magnetic carbon nanotubes. Water Res. 2013, 47, 4198-4205. pdf. supplementary materials and movies 1, 2, 3, 4, and 5 (avi format).
  21. Singh, A.; Wang, H.; Casquinha da Silva, L.; Na, C.; Prieto, M.; Futerman, A.; Luberto, C.; Del Poeta, M. Methylation of glycosylated sphingolipid modulates membrane lipid topography and pathogenicity of Cryptococcus neoformans. Cell. Microbiol. 2012, 14, 500-516. pdf. supplementary materials.
  22. Na, C.; Olson, T. M. Disinfectant and byproduct analysis in water treatment by membrane introduction mass spectrometry. In Applied Handbook of Mass Spectrometry; Lee, M. S., Ed.; John Wiley & Sons, 2012. pdf. Table of Contents.
  23. An, D.; Na, C.; Bielawski, J.; Hannun, Y.; Kasper, D. L. Membrane sphingolipidsas essential molecular signals for Bacteroides survival in the intestine. Proc. Natl. Acad. Sci. U.S.A. 2011, 108, 4666-4671. pdf. supporting information.
  24. Na, C.; McNamara, C. J.; Konkol, N. R.; Bearce, K. A.; Mitchell, R.; Martin, S. T. The use of force volume microscopy to examine bacterial attachment to surfaces. Ann. Microbiol. 2010, 6, 495-502. pdf. supplementary material.
  25. Liu, G.; Talley, J. W.; Na, C.; Larson, S. L.; Wolfe, L. G. Copper doping improves hydroxyapatite sorption for arsenate in simulated groundwaters. Environ. Sci. Technol. 2010, 44, 1366-1372. pdf. supporting information.
  26. Na, C.; Martin, S. T. Growth of manganese oxide nanostructures alters the layout of adhesion on a carbonate substrate. Environ. Sci. Technol. 2009, 43, 4967-4972. pdf. supporting information.
  27. Na, C.; Martin, S. T. Interfacial forces are modified by the growth of surface nanostructures. Environ. Sci. Technol. 2008, 42, 6883-6889. pdf. supporting information. Awarded first-runner up as best Environmental Science paper by the jouranl for the year. Journal comments and news story.
  28. Kendall, T. A.; Na, C.; Jun, Y.; Martin, S. T. Electrical properties of mineral surfaces for increasing water sorption. Langmuir 2008, 24, 2519-2524. pdf.
  29. Na, C.; Kendall, T. A.; Martin, S. T. Surface potential heterogeneity of reacted calcite and rhodochrosite. Environ. Sci. Technol. 2007, 41, 6491-6497. pdf. supporting information and movie.
  30. Na, C.; Olson, T. M. Relative reactivity of amino acids with chlorine in mixtures. Environ. Sci. Technol. 2007, 41, 3220-3225. pdf.
  31. Na, C.; Olson, T. M. Mechanism and kinetics of cyanogen chloride formation from the chlorination of glycine. Environ. Sci. Technol. 2006, 40, 1469-1477. pdf. supporting information.
  32. Lee, J. H.; Na, C., Ramirez, R. C.; Olson, T. M. Cyanogen chloride precursor analysis in chlorinated river water. Environ. Sci. Technol. 2006, 40, 1478-1484. pdf. supporting information.
  33. Cannon, F. S.; Parette, R. B.; Na, C.; Chen, W.; Hagerup, B. M. Method for perchlorate removal from ground water. US Patent. NO. 7,157,006, 2005.
  34. Na, C.; Olson, T. M. Stability of cyanogen chloride in the presence of free chlorine and monochloramine. Environ. Sci. Technol. 2004, 38, 6037-6043. pdf.
  35. Na, C.; Cannon, F. S.; Hagerup, B. M. Perchlorate removal via iron-preloaded GAC and borohydride regeneration. J. Am. Water Works Ass. 2002, 94, 90-102. pdf.

Light-Induced Phase Transition

Semiconducting crystals, well-known to be photoactive, are found to undertake phase transition upon the absorption of light. New models are needed to explain the stability and transition between different microscopic phases.

Self-Assembly in Cell Membrane

Self-assembly of amphiphilic lipids is important for membrane organization and integrity, which can be disturbed by genetic mutation of methylation. New models are needed to understand the on-off switch of self-assembly by the presence and absence of simple chemical functional groups.

Non-Covalent Bonding of π Electrons

The cation−π interaction is an important mechanism for the adsorption of aromatic hydrocarbons having non-zero quadrupole moments to solid surfaces. New models are needed explain the non-covalent interaction and predict its importance in the environment.