Show/Hide Menu
Hide/Show Apps
Logout
Türkçe
Türkçe
Search
Search
Login
Login
OpenMETU
OpenMETU
About
About
Open Science Policy
Open Science Policy
Communities & Collections
Communities & Collections
Help
Help
Frequently Asked Questions
Frequently Asked Questions
Guides
Guides
Thesis submission
Thesis submission
MS without thesis term project submission
MS without thesis term project submission
Publication submission with DOI
Publication submission with DOI
Publication submission
Publication submission
Supporting Information
Supporting Information
General Information
General Information
Copyright, Embargo and License
Copyright, Embargo and License
Contact us
Contact us
Voltammetric (micro)electrodes for the in situ study of Fe2+ oxidation kinetics in hot springs and S2O32- production at hydrothermal vents
Date
2008-02-01
Author
Mullaugh, Katherine M.
Luther, George W.
Ma, Shufen
Moore, Tommy S.
Yücel, Mustafa
Becker, Erin L.
Podowski, Elizabeth L.
Fisher, Charles R.
Trouwborst, Robert E.
Pierson, Beverly K.
Metadata
Show full item record
This work is licensed under a
Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License
.
Item Usage Stats
50
views
0
downloads
Cite This
We have used solid-state Au/Hg voltammetric electrodes to understand redox and biogeochemical processes in hot spring and deep sea hydrothermal environments. These electrodes are non-specific and have the capability of measuring simultaneously a suite of chemical species including several of the principal redox species involved in early diagenesis (O-2, Mn2+, Fe2+, H2S/HS-, and I-) as well as some Fe species (FeS and Fe3+) and sulfur species (S-x(2-) and S2O32-). Here we demonstrate how in situ data obtained in complex environments can be used to study specific iron and sulfur reactions and processes at (sub)millimeter to centimeter resolution and over short time scales. Examples include the oxidation of Fe2+ by O-2 produced by cyanobacterial mats in Yellowstone National Park hot springs and the formation of S2O32- in diffuse flow waters from the hydrothermal vents at Lau Basin. In one example, profiles of redox species in cyanobacterial mats from Yellowstone National Park hot springs show that in the light dissolved Fe2+ is completely removed from the source waters as cyanobacterial mats produce O-2 and oxidize the Fe2+. Performing kinetic experiments in the dark and light at the depth of maximum O-2 production indicates that the decay of Fe2+ follows a zero order rate law consistent with photosynthesis as the source of 0, These dynamic environments show how kinetic data can be obtained in situ and be used to understand the interactions between biology and chemistry. We know of no other analytical technique that can provide this information in both clear and turbid waters on the time scales (seconds) observed.
Subject Keywords
Thiosulfate
,
Fe2+ oxidation
,
Vents
,
Hydrothermal
,
Sediments
,
Cyanobacterial mats
,
Voltammetry and in situ analyses
,
Solid state electrodes
URI
https://hdl.handle.net/11511/32086
Journal
ELECTROANALYSIS
DOI
https://doi.org/10.1002/elan.200704056
Collections
Graduate School of Marine Sciences, Article
Suggestions
OpenMETU
Core
High temperature chemistry of some borophosphates, phase relations and structural studies
Seyyidoğlu, Semih; Kızılyallı, Meral; Department of Chemistry (2003)
The solid state, hydrothermal and flux methods were used for the investigation of alkaline earth and transition metal borophosphate compounds. The products and the phase relations were investigated by XRD, IR, DTA, and EDX methods. The solid state reactions of several boron compounds with different phosphating agents have been studied in the temperature range of 400-1200 oC. Hydrothermal and flux techniques were performed at 150 oC and 1200 oC, respectively. On the other hand, an attempt has been made to pr...
Photoexcitation Dynamics in Films of C-60 and Zn Phthalocyanine with a Layered Nanostructure
Lane, Paul A.; Cunningham, Paul D.; Melinger, Joseph S.; Kushto, Gary P.; Esentürk, Okan; Heilweil, Edwin J. (2012-02-15)
We elucidate photoexcitation dynamics in C-60 and zinc phthalocyanine (ZnPc) from picoseconds to milliseconds by transient absorption and time-resolved terahertz spectroscopy. Autoionization of C-60 is a precursor to photocarrier generation. Decay of the terahertz signal is due to decreasing photocarrier mobility over the first 20 ps and thereafter reflects recombination dynamics. Singlet diffusion rates in C-60 are determined by modeling the rise of ground state bleaching of ZnPc absorption following C-60 ...
On the Limits of Photocatalytic Water Splitting
İpek Torun, Bahar; Üner, Deniz (2019-01-01)
The major drawbacks on the limited H2 and O2 evolution activities of one-step photocatalytic water splitting systems are given here with the emphasis on charge recombination, back-oxidation reactions, and mass transfer limitations. Suppression of these unwanted phenomena is shown to be possible with the usage of small crystal-sized photocatalysts with low defect concentrations, presence of phase junctions, selection of co-catalyst that would be active for H2 evolution but inactive for O2 reduction, coating ...
Superlocal chemical reaction equilibrium in low temperature plasma
Üner, Necip Berker; Thimsen, Elijah (2020-06-01)
Low temperature plasmas (LTP) are a unique class of open-driven systems in which chemical reactions are unpredictable using established concepts. The terminal state of chemical reactions in LTP, termed the superlocal equilibrium state, is hypothesized to be defined by a proposed set of state variables. Using a LTP reactor wherein the state variables have been measured, it is shown that CO2 spontaneously splits and the effluent speciation is independent of the influent speciation if the state variables are h...
Structural peculiarities and aging effect in hydrogenated a-Si prepared by inductively coupled plasma assisted chemical vapor deposition technique
Nogay, G.; Ozkol, E.; Ilday, S.; Turan, Raşit (2014-12-01)
In this study, we report the morphological and structural properties of amorphous and nanocrystalline Si thin films deposited by inductively coupled plasma-assisted chemical vapor deposition (ICP-CVD) technique at low substrate temperatures using H-2 diluted SiH4 as the source gas. We demonstrated that changing the total deposition pressure across a broad range alters the film properties. The film grew in a columnar fashion, and its topography was rough at nanoscale as identified by high resolution Transmis...
Citation Formats
IEEE
ACM
APA
CHICAGO
MLA
BibTeX
K. M. Mullaugh et al., “Voltammetric (micro)electrodes for the in situ study of Fe2+ oxidation kinetics in hot springs and S2O32- production at hydrothermal vents,”
ELECTROANALYSIS
, pp. 280–290, 2008, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/32086.