OF NAVAL RESEARCH. Technical Report No. 87. Prepared for Publication. in the.. v.. il and/or -- c Spocial Journal of Elactroanalytical Chemistry it

Transcription

1 ,~OFFICE OF NAVAL RESEARCH Contract N K-0556 Technical Report No. 87. Th., Combined Influence of Solution Resistance and Charge-Transfer Kinetics on Microelectrode Cyclic Voltammetry oo i Acee'ic (%J by D'< T,? 0,.. ic, at i on -. N L. K. Safford and M. J. Weaver Fr' Prepared for Publication I! bvnt In n/ 1 Avnjlxjb,41ty Codes in the.. v.. il and/or -- c Spocial Journal of Elactroanalytical Chemistry it Purdue UniversityI T IC 0 Department of Chemistry West Lafayette, Indiana I July 1, 1989 Reprod,.ction in whole, or in part, is permitted for any purpose of the United States Covernment. * This documeit has been approved for public releas% and sale: its distribution is unlimited. 89 o34

2 HCURiTY CLASSITICATION O TNIS PAGE REPORT DOCUMENTATION PAGE *. REPORT SECURITY CLAS$IFICA1ION 1b RESTRICTIVE MARKINGS Unclassified a SECURITY CLASSIFICATION AUTMORITY 3 DISTRIB jtion/ AVAILABILITY OF REPORT b DECLASSIFICATION idowngrading SCHEDULE Approved for public release and sale; its distribution is unlimited. * PERFORMING ORGANIZATION REPORT NUMBER(S) 5 MONITORING ORGANIZATION REPORT NUMBER(S) Technical Report No. 87 4a. NAME OF PERFORMING ORGANIZATION 60 OFFICE SYMBOL 7& NAME OF MONITORING ORGANIZATION Purdue University (If applicable) Division of Sponsored Programs Department of Chemistry Purdue Research Foundation C ADDRESS (City. State. and ZIPCode) 7b. ADDRESS (City, State. and ZIP Code) Purdue University Purdue University Department of Chemistry West Lafayette, Indiana West Lafayette, Indiana a NAME OF FUNDINGiSPONSORING 8b OFFICE SYMBOL 9 PROCUREMENT INSTRUMENT IDENTIFICATION NUjVMBER ORGANIZATION (if applicable) Office of Naval Research ADDRESS (City. State. and ZIP Code) Contract No. NO K SOURCE Of FUNDING NUMBERS 800 N. Quincy Street PROGRAM PROJECT TASK WvORK UNIT Arlington, VA ELEMENT NO NO - NO ACCESSION NO I TITLE Arigon (Include Security Classification) The Combined Influence of Solution Resistance and Charge-Transfer Kinetics on Microelectrode Cyclic Voltanmmetry 2 PERSONAL AUTHOR(S) L. K. Safford and M. J. Weaver 3& TYPE OF REPORT 3b TIME COvERED 14 DATE OF REPORT (Year. Month. Day) 1S PAGE COUNT Technical FROM I0/I/87 TO 6/30/89 July 1, SUPPLEMENTARY NOTATION A221 7 COSATI CODES I. 8 SUBJECT TERMS (Continue on reverse if necessary an identify by block number) FIELD GROUP sue.group /,A-'icroelectrode. -cyclic voltammetry,' heterogeneous kinetics,- FE GOO solution resistance' digital simulation / 7,," 9 ABSTRACT (Continue on reverse if necessary and identify by block number) - The effects of heterogeneous kinetics on cyclic voltammograms at microdisk electrodes are examined by digital simulation. The increased diffusive efficiency at microelectrodes raises the upper limit of measurable rate constant relative to a large electrode. Solution resistance, often considered to be insignificant at microelectrodes, is shown to have potentially serious influence on the shape of the vo1tammogram. When solution resistance and heterogeneous kinetics are combined, the results suggest complex coupling between the effects of these parameters, thus making their separation difficult. / j. 20 DISTRIBUTIONAVAILABILITY OF ABSTRACT 21 ABSTRACT SECURITY CIASSIFICATION El UNCLASSIFIEDWUNLIMITED Q SAME AS RPT [ DTIC USERS '2. NAME OF RESPONSIBLE individual 22b TELEPHONE (IncLde Ar Co 22 OFFICE SYMBOL )D FORM Bil MAR 83 APR edtion may be used until eahausted SECURITY CLASSIFICATION OF THIS PAGE All othe, editions are obsolete

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