1
|
Knoche Gupta K, Lee HC, Leddy J. Magnetoelectrocatalysis: Evidence from the Hydrogen Evolution Reaction. ACS PHYSICAL CHEMISTRY AU 2024; 4:148-159. [PMID: 38560752 PMCID: PMC10979484 DOI: 10.1021/acsphyschemau.3c00039] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/07/2023] [Revised: 11/23/2023] [Accepted: 11/27/2023] [Indexed: 04/04/2024]
Abstract
Hydrogen evolution reaction (HER) rates are higher where magnetic gradients are established at electrode surfaces. In comparison of literature data for metals with comparable work functions, we note 1000× higher rates for paramagnetic metals than diamagnetic metals. With unpaired electron spins, paramagnetic and ferromagnetic metals establish interfacial magnetic gradients. At diamagnetic electrodes, gradients are induced by addition of magnetized microparticles. Onset of hydrogen evolution for magnetized γ-Fe2O3 microparticles in Nafion on diamagnetic glassy carbon electrodes is lower by 190 mV (-18 kJ mol-1) relative to demagnetized microparticles. Chemically the same as demagnetized particles, the physical distinction of magnetic field and gradient at magnetized microparticles increases electron transfer rate. For magnetized Fe3O4 microparticles, the onset is lower by 280 mV (-27 kJ mol-1). Paramagnetic platinum electrodes are unaffected by addition of magnetized microparticles. Magnetoelectrocatalysis is established by magnetic gradients.
Collapse
Affiliation(s)
| | | | - Johna Leddy
- Department of Chemistry, University
of Iowa, Iowa City, Iowa 52240, United States
| |
Collapse
|
2
|
Boselli E, Wu Z, Friedman A, Henn BC, Papautsky I. Validation of Electrochemical Sensor for Determination of Manganese in Drinking Water. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2021; 55:7501-7509. [PMID: 34009956 PMCID: PMC10704915 DOI: 10.1021/acs.est.0c05929] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Manganese (Mn) is an essential nutrient for metabolic functions, yet excessive exposure can lead to neurological disease in adults and neurodevelopmental deficits in children. Drinking water represents one of the routes of excessive Mn exposure. Both natural enrichment from rocks and soil, and man-made contamination can pollute groundwater that supplies drinking water for a substantial fraction of the U.S. population. Conventional methods for Mn monitoring in drinking water are costly and involve a long turn-around time. Recent advancements in electrochemical sensing, however, have led to the development of miniature sensors for Mn determination. These sensors rely on a cathodic stripping voltammetry electroanalytical technique on a miniaturized platinum working electrode. In this study, we validate these electrochemical sensors for the determination of Mn concentrations in drinking water against the standard method using inductively coupled plasma mass spectrometry (ICP-MS). Drinking water samples (n = 78) in the 0.03 ppb to 5.3 ppm range were analyzed. Comparisons with ICP-MS yielded 100% agreement, ∼70% accuracy, and ∼91% precision. We envision the use of our system for rapid and inexpensive point-of-use identification of Mn levels in drinking water, which is especially valuable for frequent monitoring where contamination is present.
Collapse
Affiliation(s)
- Elena Boselli
- Department of Bioengineering, University of Illinois at Chicago, IL
| | - Zhizhen Wu
- Department of Bioengineering, University of Illinois at Chicago, IL
| | - Alexa Friedman
- Department of Environmental Health, Boston University School of Public Health, Boston, MA
| | - Birgit Claus Henn
- Department of Environmental Health, Boston University School of Public Health, Boston, MA
| | - Ian Papautsky
- Department of Bioengineering, University of Illinois at Chicago, IL
| |
Collapse
|
3
|
Martín-Yerga D, Fanjul-Bolado P, Hernández-Santos D, Costa-García A. Enhanced detection of quantum dots by the magnetohydrodynamic effect for electrochemical biosensing. Analyst 2017; 142:1591-1600. [DOI: 10.1039/c7an00086c] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Magnetoelectrochemistry support for screen-printed electrodes.
Collapse
Affiliation(s)
- Daniel Martín-Yerga
- Departamento de Química Física y Analítica
- Universidad de Oviedo
- 33006 Oviedo
- Spain
| | | | | | - Agustín Costa-García
- Departamento de Química Física y Analítica
- Universidad de Oviedo
- 33006 Oviedo
- Spain
| |
Collapse
|
4
|
Weston MC, Nash CK, Homesley JJ, Fritsch I. Maximizing Flow Velocities in Redox-Magnetohydrodynamic Microfluidics Using the Transient Faradaic Current. Anal Chem 2012; 84:9402-9. [DOI: 10.1021/ac302063a] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Melissa C. Weston
- Department
of Chemistry and Biochemistry, University of Arkansas, Fayetteville, Arkansas 72701,
United States
| | - Christena K. Nash
- Department
of Chemistry and Biochemistry, University of Arkansas, Fayetteville, Arkansas 72701,
United States
| | - Jerry J. Homesley
- Department
of Chemistry and Biochemistry, University of Arkansas, Fayetteville, Arkansas 72701,
United States
| | - Ingrid Fritsch
- Department
of Chemistry and Biochemistry, University of Arkansas, Fayetteville, Arkansas 72701,
United States
| |
Collapse
|
5
|
Mühlenhoff S, Mutschke G, Koschichow D, Yang X, Bund A, Fröhlich J, Odenbach S, Eckert K. Lorentz-force-driven convection during copper magnetoelectrolysis in the presence of a supporting buoyancy force. Electrochim Acta 2012. [DOI: 10.1016/j.electacta.2012.02.110] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
|
6
|
Ensafi AA, Nazari Z, Fritsch I. Redox magnetohydrodynamics enhancement of stripping voltammetry of lead(ii), cadmium(ii) and zinc(ii) ions using 1,4-benzoquinone as an alternative pumping species. Analyst 2012; 137:424-31. [DOI: 10.1039/c1an15700k] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
|
7
|
Weston MC, Nash CK, Fritsch I. Redox-magnetohydrodynamic microfluidics without channels and compatible with electrochemical detection under immunoassay conditions. Anal Chem 2011; 82:7068-72. [PMID: 20681513 DOI: 10.1021/ac101377a] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A unique capability of redox-magnetohydrodynamics (redox-MHD) for handling liquids on a small scale was demonstrated. A 1.2 muL solution plug was pumped from an injection site to a detector without the need for a channel to direct the flow. The redox pumping species did not interfere with enzymatic activity in a solution compatible with enzyme-linked immunoassays. Alkaline phosphatase (AP), a common enzyme label, converted p-aminophenyl phosphate (PAPP) to p-aminophenol (PAP(R)) in the presence of 2.5 mM Ru(NH(3))(6)Cl(2) and 2.5 mM Ru(NH(3))(6) Cl(3), in 0.1 M Tris buffer (pH = 9). A solution plug containing PAPP (no AP) was pumped through the surrounding solution containing AP (no PAPP), and the enzymatically generated PAP(R) was easily detected and distinguishable electrochemically from the pumping species with square wave voltammetry down to 0.1 mM concentrations. The test device consisted of a silicon chip containing individually addressable microband electrodes, placed on a 0.5 T NdFeB permanent magnet with the field oriented perpendicular to the chip. A 8.0 mm wide x 15.5 mm long x 1.5 mm high volume of solution was contained by a poly(dimethylsiloxane) gasket and capped with a glass slide. A steady-state fluid velocity of approximately 30 mum/s was generated in a reinforcing flow configuration between oppositely polarized sets of pumping electrodes with approximately 2.1 muA.
Collapse
Affiliation(s)
- Melissa C Weston
- Department of Chemistry and Biochemistry, University of Arkansas, Fayetteville, Arkansas 72701, USA
| | | | | |
Collapse
|
8
|
|
9
|
Anderson EC, Weston MC, Fritsch I. Investigations of Redox Magnetohydrodynamic Fluid Flow At Microelectrode Arrays Using Microbeads. Anal Chem 2010; 82:2643-51. [PMID: 20210341 DOI: 10.1021/ac9020177] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Emily C. Anderson
- Department of Chemistry and Biochemistry, University of Arkansas, Fayetteville, Arkansas 72701
| | - Melissa C. Weston
- Department of Chemistry and Biochemistry, University of Arkansas, Fayetteville, Arkansas 72701
| | - Ingrid Fritsch
- Department of Chemistry and Biochemistry, University of Arkansas, Fayetteville, Arkansas 72701
| |
Collapse
|
10
|
|
11
|
Panta YM, Farmer DE, Johnson P, Cheney MA, Qian S. Preparation of alpha sources using magnetohydrodynamic electrodeposition for radionuclide metrology. J Colloid Interface Sci 2010; 342:128-34. [DOI: 10.1016/j.jcis.2009.09.032] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2009] [Revised: 08/29/2009] [Accepted: 09/18/2009] [Indexed: 11/25/2022]
|
12
|
Panta YM, Liu J, Cheney MA, Joo SW, Qian S. Ultrasensitive detection of mercury (II) ions using electrochemical surface plasmon resonance with magnetohydrodynamic convection. J Colloid Interface Sci 2009; 333:485-90. [DOI: 10.1016/j.jcis.2009.02.026] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2008] [Revised: 02/09/2009] [Accepted: 02/10/2009] [Indexed: 10/21/2022]
|
13
|
Affiliation(s)
- Benjamin J Privett
- Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA
| | | | | |
Collapse
|
14
|
Panta YM, Qian S, Cheney MA. Stripping analysis of mercury(II) ionic solutions under magneto-hydrodynamic convection. J Colloid Interface Sci 2007; 317:175-82. [PMID: 17919650 DOI: 10.1016/j.jcis.2007.08.049] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2007] [Revised: 08/22/2007] [Accepted: 08/24/2007] [Indexed: 10/22/2022]
Abstract
Inorganic mercury(II) ions are ubiquitous contaminants of world water systems and thus their determination and removal from the environment are important. The effects of magnetic field on the stripping analysis of mercury(II) ionic solutions have been experimentally investigated. During the stripping analysis, a potential difference is applied across the working and reference electrodes positioned in the working sample and a current density transmits through the electrolyte solution. When the electrochemical cell is exposed to a magnetic field, provided by a permanent magnet, the interaction between the current density and the magnetic field induces Lorentz forces, which, in turn, induce fluid motion. The induced magneto-hydrodynamic (MHD) convection enhances the ionic mass transport during the deposition and stripping steps, which leads to larger anodic current during the stripping step, thus obtaining higher detection sensitivity during the determination of the mercury(II) ions. The Hg2+ ionic solutions with concentrations ranging from 1 nM to 1 microM in the presence and absence of supporting electrolyte, 30 mM nitric acid (HNO 3) and 0.1 M potassium nitrate (KNO 3), under various magnetic flux densities (B=0,0.27,0.53, and 0.71 T) were measured with a linear sweep stripping voltammetry (LSSV) technique. The experimental results demonstrated that the stripping signals of the Hg2+ ions are enhanced, respectively, more than 10 and 30% in the absence and presence of the supporting electrolyte under a magnetic flux density B=0.71 T as compared to the cases in the absence of the magnetic field with all other identical conditions.
Collapse
Affiliation(s)
- Yogendra M Panta
- Department of Mechanical Engineering, University of Nevada Las Vegas, 4505 Maryland Parkway, Las Vegas, NV 89154-4027, USA
| | | | | |
Collapse
|
15
|
Weston MC, Anderson EC, Arumugam PU, Narasimhan PY, Fritsch I. Redox magnetohydrodynamic enhancement of stripping voltammetry: toward portable analysis using disposable electrodes, permanent magnets, and small volumes. Analyst 2006; 131:1322-31. [PMID: 17124540 DOI: 10.1039/b605139a] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The use of redox magnetohydrodynamics (MHD) to enhance the anodic stripping voltammetry (ASV) response of heavy metals has been investigated, with respect to achieving portability: disposable electrodes consisting of screen-printed carbon (SPC) on a low temperature co-fired ceramic (LTCC) substrate, small volumes, and permanent magnets. The analytes tested (Cd(2+), Cu(2+), and Pb(2+)) were codeposited on SPC with Hg(2+) to form a Hg thin film electrode. High concentrations of Fe(3+) were used to produce a high cathodic current which generates a significant Lorentz force in the presence of a magnetic field. This Lorentz force induces solution convection during the deposition step, enhancing the mass transport of analytes to the electrode and increasing their preconcentrated quantity in the mercury thin film. Therefore, larger ASV peaks and improved sensitivities are obtained, compared to analyses performed without a magnet. The effects on ASV signal of varying Hg(2+) concentration (0.10 and 1.0 mM), deposition time (10-600 s), and electrode surface roughness were investigated. In addition, analyses were performed using a real lake water matrix. By using the disposable LTCC-SPC working electrodes in small volumes (150 microL) and with small permanent magnets (0.78 T), peak areas were increased by 75% when compared to the signal obtained in the absence of a magnetic field. A limit of detection of 25 nM for Cd(2+) was observed with only a 1 min preconcentration time.
Collapse
Affiliation(s)
- Melissa C Weston
- Department of Chemistry and Biochemistry, University of Arkansas, Fayetteville, AR 72701, USA
| | | | | | | | | |
Collapse
|