Author Archive

Hydrogen and Oxides: Solid Protonic Conductor[1,2] as Electrolyte in Batteries, Catalytic Activator[2] on Heterostructure, Modificator[3] of Charge and Spin Subsystems

April 18th, 2015 Comments off

1.   Solid Hydroxide Eutectics as Self-Organized Nanostructured Electrolytes for Small-Sized and Low- Power Electrochemical Devices at Intermediate Temperatures Range

Yu.M. Baikov, B.T.Melekh, V.A.Klimov, V.M.Egorov
Ioffe Physico-Technical Institute, St Petersburg, Russia

Nanostructured eutectics (NaOH+KOH),(KOH+KOH.H2O), (LiOH+NaOH),  (KNH2+NaNH2) have sufficiently more higher ionic (protonic) conductivity than their  “parent” individual compounds. Studying such phenomena is useful for physics of nano-materials as well as for promising technological application for synthesis and using for energy storage and conversion.

Full article available here
Solid Hydroxide Eutectics as Self-Organized Nanostructured

2.  Little-known catalytic and electrochemical activity of solid alkaline hydroxides for energy conversion and storage

Yu.M. Baikov,  E.I. Nikulin,  B.T. Melekh,  M.E.Kompan
Ioffe Physical Tekhnical Institute, Solid State Physics,Polytekhnicheskaja 26, St-Petersburg 194021

The effectiveness of chemical reactions used for energy conversion and storage is due to opportunity  of    ‘participants’    to  activate  mutually  or  one  by  one,  e.g.  the  activation  of dihydrogen as fuel by metallic electrodes. However, the crucial role, as a rules, play  catalytic agents or electric field, particularly to finding new arrangements of processes and devices for energy conversion and storage. Recently new (or little known) combinations of electrolytes and electrodes were found and presented in our papers [1-3]. The main part of them are different forms of solid ALKALINE [4] hydroxides.

Full article available here
Little-known catalytic and electrochemical activity of solid alkaline hydroxides for energy conversion and storage

 3. Chemical effect on spin-electron subsystem of transition metal oxides

Yurii M. Baikov*, B.T.Melekh, E.I.Nikulin
Ioffe Physical Technical Institute, St. Petersburg, Russia

Now one can say not only on the influence of spin subsystem on chemical properties , but also on possible chemical modification of spin subsystem. In this sense, the most effective way   is controlled   changing   of   the   number   of   electrons   by   mild   chemical   reactions.   Such physico-chemical modification is presented for somewhat different, chemically modified oxides of transition metal, namely, YBa2Cu3O7, LaMn1-x(Ca/Sr)xO3, CexSr1-xMnO3, as initial compounds.

Full article available here
Chemical effect on spin-electron subsystem of transition metal oxides


History of INTAS 99-0636. Hydrogen in Oxides.

January 6th, 2015 11 comments

Electrochemical Cells Video Demonstration

November 29th, 2014 Comments off


Protonic and Oxygen Quasichemistry in Solid Oxides

April 22nd, 2012 Comments off

Dear Colleagues!

Please consider and discuss below presented сomplete quasichemical description of some cubic oxides similar YO1.5 and double perovskites in water and oxygen atmosphere

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Advanced themes of scientific talk about protonic conductors

January 27th, 2012 Comments off

I would like to propose for starters to divide the set of subjects onto two groups according to remarks in “Introduction” about preferably my personal interest (items ”a” and “b”) and evidently common interest (items “c” and “d”). Of course such division has enough relative character, but, by my opinion, it seems suitable.

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Little known heterostructures “compound alkaline electrolyte – electron conductor”: hydroxide ion as a proton acceptor and an electrochemically active species

January 3rd, 2012 1 comment

Yu. M. Baikov, E. I. Nikulin, B. T. Melekh, L. G. Baikova


The family of complex materials such as crystalline hydrates and solid eutectics, on the base of hydroxides of alkaline metals (Na, K, Rb, Cs) has been studied thoroughly from the general physico-chemical point of view. However, the high proton conductivity of the members of this family has been revealed on for the last few years. Correspondingly there was no information on the electrochemical activity of heterostructures “alkaline proton | electron conductor”. In our opinion the crucial reason for this objectionable approach of world ionic community to whole alkaline-hydroxide-family was due to dramatic history of arising and then falling of interest in individual alkaline hydroxides. The key aim of the paper is to present our results of the development of solid and molten hydroxide materials which are good proton conductors at intermediate / room temperatures (450 < T < 250K) and low-humidity or even anhydrous conditions, as well as are electrochemically active in MEA with Ti, TiFe, Sn and Si. The main experimental results and informal discussions on necessary further progress in fundamental understanding of the underlying proton conduction mechanisms are collected now on website


Hydrogen and oxygen species in mass and charge transport across and along interfaces of novel electrolytes on the base of alkaline hydroxides

January 3rd, 2012 1 comment

Authors : Yu. M. Baikov, E. I. Nikulin, B. T. Melekh, V. A. Klimov

“Old” isotopic methods, namely both isotopic exchange (IsEx) and isotopic effect(IsEff), are the effective characterization technique at the study of interface and surface processes at different length scales. Factually, they are in-situ techniques of significant importance at the study of mass and charge transport across and along interfaces of recently discovered ionic conductors on the base of alkaline hydroxides, namely crystalline KOH·H2O (Tmelt=146°C) and KOH·2H2O (Tmelt=42°C) as individual compounds and solid eutectic NaOH+KOH (ENaK) (Tmelt=185°C). See The isotopic technique supplied to traditional physico- and electrochemical techniques is factually phenomenological modelling for a deeper understanding of the underlying transport and reactivity mechanisms. We present the results of the study of IsEff (H<=>D) of both the conductivity and EMF of the heterojunction electrode|protonics as well as IsEx “gas-electrolyte” and “electrode-electrolyte”. The rate of IsEx “gas(H2)-a.m.electrolytes” was compared with the exchange-current on the interface “TiHx(or PdHy)| a.m.electrolytes”. The main conclusions are following. i)The mobility of hydrogen species is higher along internal interfaces than across them in the microheterogenic ENaK. ii) The reality of hydrogen heterojunction has been confirmed. iii) The surface of hydroxides itself can activate the molecular hydrogen.


Isotopic effect of voltammetry

November 19th, 2011 Comments off

Comparison of electrochemical cells with different isotoppic conten in electrolyte


Comparison of electrochemical cells with different isotoppic conten in electrolyte

Isotopic effect of voltammetry



November 15th, 2011 Comments off

Yu.M.Baikov,  B.T.Melekh, V.A.Klimov, E.I.Nikulin, L.G.Baikova


Ioffe Physical Technical Institute of RAS, Saint-Petersburg,                                194021 Russian Federation,


Fig.1 Simple  model electrochemical cell.          The details: glass tube as a case; metallic Sn and graphite as electrodes; solid electrolyte obtained after cooling the melt of  61w % of KOH and 39 w %  H2O.Lighting head of match for scaling.

Sn(-)|KOH·2H2O| C(+)

protonic conducter cells

The semiconductor-protonic heterojunction in the heterostructure ‘C(+)|KOH·2H2O|Si(-)’ could be considered as the opportunity of the matching of small-sized electronic devices with batteries studied  here.

Compound compositions NaOH, KOH, H2O of lower melting points showed high proton conductivity at 300-450 K1,2. They are  eutectics KOH\KOH·H2O (372.5K), KOH\NaOH(448K), and KOH·H2O (419K) and  NaOH·H2O (338K).

The pioneering investigation of the electrochemical activity of certain ionic heterostructures with solid electrolyte KOH·2H2O (Tmelt=315 K) is due to basic and applied interest in. The special study of different chemical elements of IV group (C, Si, Sn, Pb) as electrodes of electrochemical cells in contact with hydroxide superproton conductor as electrolyte has been performed.

Table 1.


EMF (1,2 – 1,3 V) and exchange currents (~0,1-1 mA/cm2) of  ‘C | KOH·2H2O | TiFe’ and  ‘C | KOH·2H2O | Sn’ are adequate to work as low-power sources for electronic devices. Therefore they could be factually batteries without any catalysts and noble metals, i.e. from cheap materials.

The metal-proton heterojunction Sn(-)|KOH·2H2O has been studied firstly. It is characterized by exchange current at 290 K (1 mA/cm2, a polish surface).


1. Yu.M.Baikov,SolidStateIonics 181 (2010) 545

2 Yu.M.Baikov, J.Power Sources 193 (2009) 371

The support of Programm of Presidium of RAS “Quantum Physics of Condensed Matter” .


Self-Diffusion of Lithium, Hydrogen, and Oxygen Ions in Crystalline Lithium Hydroxide

November 14th, 2011 Comments off

Abstract—The self-diffusion coefficients of ions of the three chemical elements forming lithium hydroxide have been determined by the crystal–crystal and crystal–gas isotope exchange method in the temperature range 500–720 K. Crystal samples with different isotope compositions have been grown by the Bridgman method from melts. The melting temperature is 743 ± 2 K. Original methods have been developed for high-precision measurements of the isotope ratios of all the three elements, i.e., lithium (6Li/7Li), hydrogen (H/D), and oxygen (16O/18O), and their changes after diffusion annealing with the use of the same sample. The self-diffusion coefficients of lithium and hydrogen ions differ but by a factor of no more than 3–5; however, their magnitudes exceeds those for oxygen by several orders of magnitude. In particular, at 670 K, they are equal to 6.0·10-9 , 3.2·10–9, and 2.0·10–12 cm2 s–1 for hydrogen, lithium, and oxygen, respectively. In the range 680–720 K, the self-diffusion coefficients of hydrogen and lithium increase sharply with increasing temperature to approximately 10–6 cm2 s–1. A probable mechanism of migration of protons and lithium ions in LiOH and the role played in this process by the oxygen ions with a lower mobility have been discussed.

DOI: 10.1134/S1063783410100070

Correction of   the equation  (5) in

Self-Diffusion of Lithium, Hydrogen, and Oxygen Ions in Crystalline Lithium Hydroxide  2010 Vol. 52,  No.10, 2044-2057 (the correction elated to third member in (5) on P.2054)

Исправление  формулы (5) в статье

ФТТ 2010  Том 52 вып 10  на стр 1917

Full article in English is here

Self of Lithium, Hydrogen, and Oxygen Ions in Crystalline Lithium Hydroxide.PDF

Full article in Russian is here

Самодиффузия ионов лития, водорода и кислорода в кристаллическом гидроксиде лития.PDF