Martin Fleischmann's research while affiliated with University of Southampton and other places

Publications (35)

Article
It is confirmed that it is possible to obtain a mathematical solution to the problem of the nucleation and three-dimensional growth at constant potential of single growth centres of a new phase on a microelectrode substrate under all conditions ranging from kinetic to diffusion control of the growth process under the assumption that diffusion is in...
Article
We present here one aspect of our recent research on the calorimetry of the Pd-D2O system which has been concerned with high rates of specific excess enthalpy generation (>1 kW cm-3 at temperatures close to (or at) the boiling point of the electrolyte solution. This has led to a particularly simple method of deriving the rate of excess enthalpy pro...
Article
The ac impedance for a simple redox reaction at microspherical and cylindrical electrodes is derived using conventional methods. An exact formalism is developed for the analysis of the behavior of microdisks and microrings which will allow the analysis of complex reactions using such electrode designs. The analysis here is restricted to the approxi...
Chapter
A general approach to the analysis of time dependent responses for electrochemical experiments at electrodes of finite size and with arbitrary shapes and surface conditions is described. Neumann’s integral theorem of two parameters is used to illustrate an application of the approach to such problems in circular cylindrical coordinates. It is shown...
Chapter
It is shown that it is possible to develop a number of strategies for the measurement of kinetics at the molecular level by using microelectrodes of sufficiently small dimensions. These strategies rely on the amplification of individual molecular and therefore stochastic events by subsequent essentially deterministic processes. The direct measureme...
Chapter
It is shown that it is possible to use microelectrodes to develop a number of strategies which allow electrochemical measurements on gas phase species. Comparisons are made with other related fields of research with particular emphasis on pulsed field desorption mass spectroscopy. Comparisons are also made with electrochemical measurements in”non-c...
Article
The technique, model, and experimental procedures as used in the Fleischmann-Pons calorimetric investigations are described. We note that the use of energy-efficient systems (D2 ionization at the anode, small interelectrode gaps, high electrolyte concentrations) would give energy-producing systems even for some of the baseline excess enthalpies alr...
Article
It is shown that accurate values of the rates of enthalpy generation in the electrolysis of light and heavy water can be obtained from measurements in simple, single compartment Dewar type calorimeter cells. This precise evaluation of the rate of enthalpy generation relies on the non-linear regression fitting of the “black-box” model of the calorim...
Article
We report the theoretical chronoamperometric response for a ring electrode of finite size, and compare the experimental response to that of a disk electrode. As expected, the response of the ring electrode approaches mass transport conditions close to those for the final steady state at times which are short compared to those at which the steady st...
Article
In this paper, we discuss the forms of the overpotential-time response to controlled current experiments at finite disk electrodes, and compare these to experimental results obtained at disk microelectrodes. With microelectrodes, fast mass transport conditions and low charging currents give rise to sharp transitions at suitably high values of the i...
Article
This paper reports how D+ was compressed galvanostatically into sheet, rod and cube samples of Pd from 0.1 M LiOD in 99.5% D2O+0.5% H2O solutions. Experiments of several kinds were performed: (1) calorimetric measurements of heat balances at low current densities; (2) calorimetric measurements at high current densities; (3) determination of γ-rays...
Article
The analysis of the transient response of a finite geometry disk electrode (embedded in an infinite insulating plane) subjected to an ac flux perturbation is discussed. The real and imaginary components of the impedance are derived. The analysis makes use of the properties of discontinuous definite Bessel integrals.
Article
We describe the time dependent response of a finite disk electrode under conditions of constant applied flux (chronopotentiometry). The exact solution is recovered by solving the differential equations in the circular cylindrical coordinate system with the use of suitable discontinuous integrals. In addition, we present the results for the case of...
Article
In this work, we discuss the solution of the differential equations in the cylindrical coordinate system for the case of a coupled CE reaction mechanism at a finite disk electrode. We use the properties of discontinuous integrals of Bessel functions to treat the mixed boundary conditions at the electrode surface and the surrounding insulator. The r...
Article
It is possible to derive the chronopotentiometric and chronoamperometric response of microdisk electrodes by modeling these experiments with a constant uniform flux over the microdisk and by deriving the average concentration over the surface. The properties of the discontinuous integrals of Bessel functions are used in these calculations to accoun...
Article
In this work, zeolite-supported Pt(O) microstructures sized less than 10 nm are accessed as electrodes using dispersion electrolysis. Modification of an heterogeneous catalyst with ultramicroelectrodes permits exploration of electrode processes in an interphase dominated by the nature of the heterogeneous catalyst and at electrode sizes where bulk...
Article
We describe in this paper the use of ultramicroelectrodes as sensitive sensors and detectors in the gas phase and in liquid solutions of high resistance; particularly aspects regarding the sensitivity, stability, and reproducibility of the devices. The advantages of these detectors can be improved notably by appropriate choice of method of pretreat...
Article
The vibrational frequencies of ferricyanide and ferrocyanide adsorbed on metal electrodes have been calculated by expansion of the potential to second order with the Cartesian form of the Taylor series. The vibrational frequencies are a strong function of electrode-adsorbate orientation and binding energy. Ion pairing with alkali-metal cations has...
Article
An exact analysis of diffusion to microdisk and microring electrodes is presented for steady-state conditions and for the assumptions of constant concentration over the surface of the disk and constant flux over the surface of the ring electrodes. Mass transfer to ring electrodes is progressively enhanced by reducing their thickness, which also red...
Article
In this work, we demonstrate the use of very thin ring ultramicroelectrodes in measuring the heterogeneous rate constants of several fast one-electron-transfer reactions under steady-state diffusion conditions. Under these conditions, the theoretical and instrumental efforts are greatly simplified compared to those required for relaxation technique...
Article
It is shown that it is possible to carry out electrochemical reactions in poorly conducting and nonconducting media by means of bipolar electrolyses with dispersions. Polarization equations are predicted for highly simplified models based on the concept of the mixture potential, the surface reactions being assumed to be rate determining. Results fo...
Article
Ultramicroelectrodes may be used in solvents containing little or no purposely added supporting electrolyte. Under these conditions, the accessible potential range is considerably extended. Oxidation of species with very high ionization potentials can be studied; oxidation of some of the rare gases and oxygen is reported in this work.
Article
It is demonstrated that ultramicroelectrodes can be used as sensitive electrochemical detectors and sensors in the gas phase. The sensitivity of these devices depends on the electrochemical properties of the analyte and on the properties of the surface separating the ultramicroelectrode from the counter electrode. The devices are demonstrated in th...
Article
Solutions of nitronium tetrafluoroborate in acetonitrile were obtained by anodic oxidation of N2O4. The electrogenerated NO2BF4 efficiently nitroacetamidates conjugated dienes. Buta-1,3-diene, isoprene, 2,3-dimethylbutadiene, trans-penta-1,3-diene and trans-trans-hexa-2,4-diene give mixtures of products by 1,2- and 1,4-addition. Structures of the 1...
Article
The bipolar electrolysis of suspensions of spherical ultramicroelectrodes is discussed. It is shown that the reactions at the surface will be rate controlling over a wide range of conditions in view of the high rates of mass transfer to the electrodes. The effects of diffusion can be taken into account in a straightforward manner in view of the abs...
Article
It is shown that ring electrodes having a small thickness and radius can be used to investigate the kinetics of fast electrode reactions by using steady-state measurements. The mass-transfer coefficient of the species to and from the electrode surface is derived wrth the assumption of uniform accessibility of the electrode surface. This mass-transf...
Article
The use of ultramicroelectrodes in aprotic solvents containing no intentionally added supporting electrolyte allows the observed anodic oxidation limit in acetonitrile to be considerably extended. The anodic oxidation of methane, butane, and other aliphatic alkanes is clearly observed under steady-state conditions at potentials up to approximately...
Article
Solutions of nitronium tetrafluoroborate in acetonitrile prepared by anodic oxidation of nitrogen dioxide, efficiently nitrate aromatics, enolsilyethers, alkenes and conjugated dienes to afford respectively nitroaromatics, α-nitroketones, vicinal nitroamides and mixtures of nitroacetamides by 1,2- and 1,4-addition.
Article
Reaction of styrenes with nitronium tetrafluoroborate in acetonitrile affords good yields of products of nitroacetamidation. In all cases addition is highly regioselective to give Markownikoff products. With trans-β-methylstyrene, conversion of the initial product of nitroacetamidation into epimeric imidazolines proves a cis-nitroacetamidation. In...

Citations

... In amperometric devices, the use of porous planar electrodes leads to the possibility of a poor potential distribution over the sensing electrode because of voltage drops within the solid electrolyte; this is avoided in the design proposed in this paper. The only papers of which we are aware and which may consider cells of equivalent design are those[16][17][18][19]describing electrochemical detectors for gas phase chromatography. These cells were fabricated with two closely spaced thin metal layers on glass. ...
... The d + and p + ions are very strongly coupled to each other, metal ions and lattice electrons thru spin exchange. Pons and Fleischmann hypothesized a sort of fermionic to bosonic superradiance of the protium and deuterium within the lattice (Fleischmann et al., 1989). The Little (Effect) Rules govern the details of spin and revorbital phenomena associated with such superradiance. ...
... electrode deposition potential and time of deposition, temperature, and electrolyte composition. [23][24][25][26] It is thus not surprising that electrodeposition has been used to make a variety of controlled Pd nanostructures such as nanowires, 17 cubes, nanoflowers, nanoframes, and high index faceted Pd nanocrystals. 11,[27][28][29] Interestingly, despite the vast number of electrodeposition studies, the majority are carried out in aqueous solutions, as is the case for Pd, using salts that contain anions such as Cl − , ClO 4 − , SO 4 −2 , NO 3 kinetics, (v) altering the diffusional properties of ions in the solvent, (vi) increasing the potential window, enabling metal reduction outside the aqueous solvent window, and (vii) increasing the variety of electrodeposition salts which can be dissolved etc. 32 Mixing two or more (miscible) solvents together offers a further control parameter in the study of electrodeposition. ...
... The small size of microelectrodes typically leads to situations where transients are short-lived and so the accompanying mass transport may be treated as steady state. Isolated microelectrodes in the shape of hemispheres (Oldham and Zoski [23]), discs (Aoki et al. [2], Bond et al. [6], Phillips [24,25], Bender and Stone [5]) and rings (Fleischmann et al. [9,10], Szabo [33], Phillips and Stone [27]) have been analyzed most frequently, mostly for the case of bulk diffusion with surface chemical reaction (the Laplace equation), but also for bulk diffusion with surface chemical reaction and bulk species regeneration by chemical reaction (the modified Helmholtz equation). ...
... Introduction. Observation of an anomalously large amount of energy in the electrolysis of heavy water reported by Fleischman and Pons over thirty years ago was interpreted as a result of deuteron-deuteron (DD) fusion reactions in the Palladium electrode [1,2]. However, the lack of experimental reproducibility and expected nuclear reaction products observed in accelerator experiments at higher deuteron energies caused strong skepticism about the data. ...
... The small size of microelectrodes typically leads to situations where transients are short-lived and so the accompanying mass transport may be treated as steady state. Isolated microelectrodes in the shape of hemispheres (Oldham and Zoski [23]), discs (Aoki et al. [2], Bond et al. [6], Phillips [24, 25], Bender and Stone [5]) and rings (Fleischmann et al. [9, 10], Szabo [33], Phillips and Stone [27]) have been analyzed most frequently, mostly for the case of bulk diffusion with surface chemical reaction (the Laplace equation), but also for bulk diffusion with surface chemical reaction and bulk species regeneration by chemical reaction (the modified Helmholtz equation). Recent electrochemical applications utilize microelectrode arrays (Wightman and Wipf [35]). ...
... Such accidental vibration may be generated during electrolysis e.g. by bubble formation. The whole process may strongly depend on constructional features (e.g., the geometry) of the apparatus (compare Fig.1.(b) of [15] and Fig.2. of [36]). ...
... In the case of very long experimental and theoretical time scales, hemispherical diffusion to microdisk electrodes [30][31][32][33] shows diffusion regimes depending on the CV scan rate or the EIS frequencies. Increasing the frequency to the characteristic value ω = D/d 2 , where D is the diffusion coefficient of the analyte and d is the distance between neighboring electrodes 34,35 , causes the transition from overlapping (Fig. 4a) to nonoverlapping (Fig. 4b) diffusion hemispheres. ...
... Deuterium fusion was further presumed to be leading to the production of helium; accounting for the proposed release of neutrons. The most striking conclusion, however, was that most of the deuterium fusion-derived energy was occurring as heat [26] [27]. The strong bias towards heat production rendered the supposed fusion process far more efficient and safer than the standard high temperature and pressure induced nuclear fusion in nuclear power plants [28]. ...
... Fleischmann and Pons have previously reported ~7x faster radial transport than vertical transport [6] in a Fleischmann-Pons-type electrolysis cell, a claim echoed in a recent publication [4]. If radial transport of the cell liquid is rapid, then entrained solids or gases could be carried along. ...