Sains Malaysiana 47(8)(2018): 1913–1922

http://dx.doi.org/10.17576/jsm-2018-4708-33

 

XPS Study of Sulfur and Phosphorus Compounds with Different Oxidation States

(Kajian XPS untuk Sebatian Sulfur dan Fosforus yang Mempunyai Pengoksidaan yang Berbeza)

 

KIM S. SIOW^1,2*, LEANNE BRITCHER¹, SUNIL KUMAR^1,3 & HANS J GRIESSER^1,4

 

¹Ian Wark Research Institute, University of South Australia, Mawson Lakes, SA 5095, Australia

 

²Institute of Microengineering and Nanoelectronics, Universiti Kebangsaan Malaysia, 43600 UKM Bangi, Selangor Darul Ehsan, Malaysia

 

³Coatings Mantra Science and Technology Consulting, 11 Beresina Place, Greenwith, Adelaide, SA 5125, Australia

 

⁴Mawson Institute, University of South Australia, Mawson Lakes, SA 5095, Australia

 

Received: 9 February 2018/Accepted: 14 March 2018

 

ABSTRACT

In this report, we demonstrate that continuous improvement in XPS instruments and the calibration standards as well as analysis with standard component-fitting procedures can be used to determine the binding energies of compounds containing phosphorus and sulfur of different oxidation states with higher confidence. Based on such improved XPS analyses, the binding energies (BEs) of S2p signals for sulfur of increasing oxidation state are determined to be 166-167.5 eV for S=O in dimethyl sulfoxide, 168.1 eV for S=O₂ in polysulfone, 168.4 eV for SO₃ in polystyrene sulfonate and 168.8 eV for SO₄ in chondroitin sulfate. The BEs of P₂p signals show the following values: 132.9 eV for PO₃ in triisopropyl phosphite, 133.3 eV for PO₄ in glycerol phosphate, 133.5 eV for PO₄ in sodium tripolyphosphate and 134.0 eV for PO₄ in sodium hexametaphosphate. These results showed that there are only small increases in the binding energy when additional oxygen atoms are added to the S-O chemical group. A similar result is obtained when the fourth oxygen or poly-phosphate environment is added to the phosphorus compound. These BE values are useful to researchers involved in identifying oxidation states of phosphorus and sulfur atoms commonly observed on modified surfaces and interfaces found in applications such as biomaterials, super-capacitors and catalysis.

Keywords: Binding energies; oxidation state; phosphoric; sulphur; XPS

 

ABSTRAK

Kajian ini menunjukkan bahawa penambahbaikan yang berterusan dalam spektroskopi foto-elektron x-ray (XPS), piawaian penentukuran dan prosedur pencocokan lengkung puncak, boleh menentukan tenaga pengikat untuk sebatian fosforus dan sulfur yang terdiri daripada pengoksidaan yang berbeza dengan lebih jitu. Berdasarkan analisis XPS ini, tenaga pengikat (BE) untuk puncak S2p daripada sebatian sulfur yang mempunyai pengoksidaan yang meningkat ialah: 166-167.5 eV untuk S=O dalam dimetil sulfoxida, 168.1 eV untuk S=O₂ dalam poli-sulfon, 168.4 eV untuk SO₃ dalam polistirena sulfonat dan 168.8 eV untuk SO₄ dalam kondroitin sulfat. BE untuk puncak P2p daripada sebatian fosforus menunjukkan bacaan berikut: 132.9 eV untuk PO₃ dalam tri-isopropil fosfit, 133.3 eV untuk PO₄ dalam fosfat gliserol, 133.5 eV untuk PO₄ dalam natrium tripolifosfat dan 134.0 eV untuk PO₄ dalam natrium hexametafosfat. Keputusan ini menunjukkan bahawa hanya ada peningkatan yang kecil dalam tenaga pengikat (eV) apabila atom oksigen ditambah kepada sebatian yang diikat oleh S-O. Keputusan yang sama diperoleh apabila persekitaran oksigen atau poli-fosfat keempat ditambah kepada sebatian fosforus. Nilai BE untuk sebatian sulfur dan fosforus ini adalah berguna untuk para penyelidik yang cuba mengenal pasti sebatian yang lazim terdapat di atas permukaan dan antara-muka untuk aplikasi seperti bio-bahan, super-kapasitor dan mangkin.

 

Kata kunci: Fosforus; keadaan pengoksidaan; spektroskopi fotoelektron x-ray; sulfur; tenaga pengikat

REFERENCES

Alexander, M.R., Short, R.D., Jones, F.R., Stollenwerk, M., Zabold, J. & Michaeli, W. 1996. An x-ray photoelectron spectroscopic investigation into the chemical structure of deposits formed from hexamethyldisiloxane/oxygen plasmas. Journal of Materials Science 31(7): 1879-1885.

Andrade, J.D. 1985. Principles of protein adsorption. In Surface and Interfacial Aspects of Biomedical Polymers, edited by Andrade, J.D. New York: Plenum Press. pp. 1-80.

ASTM. 2010. E2108-10 Standard practice for calibration of the electron binding-energy scale of an x-ray photoelectron spectrometer. West Conshohocken, PA: ASTM.

Austin, B.B. 1978. Errors in Practical Measurement in Science, Engineering and Technology. New York: Wiley-Interscience Publication.

Beamson, G. & Briggs, D. 1992. High Resolution XPS of Organic Polymers. New York: Wiley.

Dietrich, P.M., Horlacher, T., Girard-Lauriault, P.L., Gross, T., Lippitz, A., Min, H., Wirth, T., Castille, R., Seeberger, P.H. & Unger, W.E.S. 2011. Adlayers of dimannoside thiols on gold: Surface chemical analysis. Langmuir 27(8): 4808-4815.

Fairley, N. 2003. XPS Lineshapes and Component Fitting in Surface Analysis by Auger and X-ray Photoelectron Spectroscopy. Chichester: IM Publications and SurfaceSpectra Limited.

Fairley, N. & Carrick, A. 2005. The Casa Cookbook: Part 1: Recipes for XPS Data Processing. Cheshire: Acolyte Science.

Giroux, T.A. & Cooper, S.L. 1991. Surface characterization of plasma-derivatized polyurethanes. Journal of Applied Polymer Science 43(1): 145-155.

Harrison, K. & Hazell, L.B. 1992. The determination of uncertainties in quantitative XPS/AES and its impact on data acquisition strategy. Surface and Interface Analysis 18(5): 368-376.

Lin, J.C. & Chuang, W.H. 2000. Synthesis, surface characterization, and platelet reactivity evaluation for the self-assembled monolayer of alkanethiol with sulfonic acid functionality. Journal of Biomedical Materials Research 51(3): 413-423.

Lin, J.C., Chen, Y.F. & Chen, C.Y. 1999. Surface characterization and platelet adhesion studies of plasma polymerized phosphite and its copolymers with dimethylsulfate. Biomaterials 20(16): 1439-1447.

Lindberg, B.J., Hamrin, K., Johansson, G., Gelius, U., Fahlman, A., Nordling, C. & Siegbahn, K. 1970. Molecular spectroscopy by means of ESCA [electron spectroscopy for chemical analysis]. II. Sulfur compounds. Correlation of electron binding energy with structure. Physica Scripta 1(5-6): 286-298.

Pelavin, M., Hendrickson, D.N., Hollander, J.M. & Jolly, W.L. 1970. Phosphorus 2p electron binding energies. Correlation with extended Hueckel charges. Journal of Physical Chemistry 74(5): 1116-1121.

Perkins, C.L. 2009. Molecular anchors for self-assembled monolayers on zno: A direct comparison of the thiol and phosphonic acid moieties. Journal of Physical Chemistry C 113(42): 18276-18286.

Ratner, B.D., & Castner, D.G. 2003. Electron spectroscopy for chemical analysis. In Surface Analysis: The Principal Techniques, edited by Vickerman, J.C. Chichester: John Wiley and Sons. pp: 43-98.

Seredych, M., Wu, C.T., Brender, P., Ania, C.O., Vix-Guterl, C. & Bandosz, T.J. 2012. Role of phosphorus in carbon matrix in desulfurization of diesel fuel using adsorption process. Fuel 92 (1):318-326.

Siow, K.S., Kumar, S. & Griesser, H.J. 2015. Low-pressure plasma methods for generating non-reactive hydrophilic and hydrogel-like bio-interface coatings - a review. Plasma Processes and Polymers 12(1): 8-24.

Siow, K.S., Leanne, B., Sunil, K. & Hans, J.G. 2014. Deposition and XPS and FTIR analysis of plasma polymer coatings containing phosphorus. Plasma Process Polymer 11(2): 133-141.

Siow, K.S., Britcher, L., Kumar, S. & Griesser, H.J. 2009. Sulfonated surfaces by sulfur dioxide plasma surface treatment of plasma polymer films. Plasma Process Polymer 6(9): 583-592.

Siow, K.S. 2007. Plasma based methods for producing controlled polymer surfaces with sulfur and phosphorus containing chemical groups and interactions between such surfaces and proteins. PhD thesis. Ian Wark Research Institute, University of South Australia (Unpublished).

Ward, A.J. & Short, R.D. 1994. A spectroscopic analysis of plasma polymers prepared from a series of vinyl sulfones. Surface and Interface Analysis 22(1-12): 477-482.

Wen, Y., Wang, B., Huang, C., Wang, L. & Hulicova-Jurcakova, D. 2015. Synthesis of phosphorus-doped graphene and its wide potential window in aqueous supercapacitors. Chemistry - A European Journal 21(1): 80-85.

 

 

*Corresponding author; email: kimsiow@ukm.edu.my