Materials For Energy - Science topic

Also check https://www.neeri.res.in/img_homes/45359441_List-of-Tentative-Ph-D-Topics.pdf

Are you visit MSCsoftware Homepage?

If you or your organization purchase these software.

There are Theory manual.

These things are just summary of academic theroy of lecture or textbook

but it is good summary.

They lead to you restudry or research our material given at university lecture time.

You shoud know time direct integration method.

Rungee Kutta (?) method.

and Finite Element Method.

There are many Numerical Schem like FVM, FDM, BEM for fluid dynamics.

But only FEM is general method and can solve every engineering problem.

But it is approximation, So, accracy depend on users' experinece, engineering sense.

I don't know about COMSOL

but gorvening equation probable same,

and calculation logic probably simmilar,

I think this time is study FEM, implicity, and Explicity.

Good luck

Hi Saty Dev

Among all of the Additive manufacturing processes, the fused deposition material used the most, because of the Economical aspects than other AM processes such as Low or moderate costs of equipment, low waste, simple set-up, the optimal time of production, and fairly efficiency.

Another advantage of FDM 3D printing is scalability: It can be easily scaled to any size and for the last, it has material flexibility for "mass and custom production".

Best regards.

I came across the same materials by doing some research on molten iron oxide electrolysis. Have you got any further with your question? Have you tried to do experiments using these electrodes?

I'm not sure about consumable electrodes.. I guess it's just doesn't feel right to replace them all the time, and it contaminates the electrolyte?

Please any one send me CIF file for NMC811 cathode material? my email adress: 3077667118@qq.com@@

Artur's comments about granular flow are correct for low speed applications like stopping a truck, but for blast loading of a geomaterial, the primary mechanism for energy dissipation is the fracture, comminution, and plastic flow of fragments to fill the local pore space during compaction. The textile container around these barriers (or a common sandbag) just serves as a robust container to hold the material in place. In some cases, there may be a pre-stress on the granular material if the casing is elastic, but the pressure from that is so small compared to that of a blast I doubt it's significant.

Good answer Dharmesh K. Oza ...

the double layer capacitance changes also with the metal surface, for high carbon steel and cast iron surface, the DL is much high

I have understood your problem. For your project you choose Green Materials and in your project rather than furniture recycling, you should focus on refurbished and salvaged materials.

The products which otherwise are found disposed as solid waste are defined as refurbished materials. These materials undergo any operation so that they are made reusable in building construction.

Refurbishing operations include following but not limited to:

· Renovating or repairing,

· Modifying the outward appearance,

· Improving quality and their the performance

· Enabling functional use and

· Adding the value

Salvaged materials are those which are recovered from the construction sites or existing buildings and reused.

These could be structural beams, floors, doors, cabinets etc. Salvaging wood or wood based products are considered very important as it not only reduces waste but also reduces demand for the virgin materials and thereby mitigate the environmental impact due to extracting and processing of the virgin materials. Form work, bracing are the illustrations.

Moreover, the refurbishing of vernacular buildings using wood and wood based products which are costly and they therefore should be reused as far as possible.Demolished wood is considered salvaged wood. Most rating systems treat wood that continues to serve its original function (e.g., walls, ceilings, flooring) in a renovation project.

In developed countries, there are shops selling reusable refurbished materials. See the advertisement given below in this context

(Source: http://www.usedbuildingmaterials.com/)

“At our retail yard and warehouse in Mt. Vernon, Washington we divert re-useable building materials from the waste stream and offer them to the public at a significant savings. Frequented by Homeowners, Contractors, Artists, Antique Dealers and Hopeful Junk Hounds, our inventory is always changing, offering an assortment of quality: doors, windows, plumbing, electrical, millwork, tile, cabinets, lumber, flooring, masonry, period pieces and much more. See what items and departments we regularly stock in our general inventory.

Hi Aranganathan,

I believe that the reference data is mostly from some well-known reviews about energy storage devices (supercapacitors and batteries). Some representative reviews are listed as below:

Nat. Mater., 2008, 7, 845–854;

Science, 2011, 334(6058): 928-935;

Chem. Soc. Rev., 2015, 44, 7484;

Adv. Sci. 2017, 1600539 For the performance comparison with commercial energy storage devices, you can find this reference: Science, 2011, 334(6058): 917-918.

Hopefully you find it useful.

I am looking for the same calculation. If you have solved the problem can you please tell step wise.

Thanks

The recent development in the synthesis of 2D materials include  graphene analogues  has shown great potential  in  energy-related applications  due to their remarkable electrochemical properties. Green synthesis of rGO is simple and eco-friendly way.  

plz go through the supporting information the following paper.

link is given below.

Thanks for your comments. Sure, i am doing in an Argon filled glove box. I will try it again based on your comments. Anode(graphite) is also from same commercial battery.

 Thank you so much Dr Schmitz.

Dear Sabramanian greetings i must recognize that such Q is so intersting. LDRs & SCs both convert radiation into electricity, but in LDRs resistivity could vary when material is illuminated (then mainly used in sensors); SCs in contrast are based on varying charge carrier mobility of semicond. (then mean life time,..) thus carriers should separated , not recombinated a second time. The 2principles are quite different. appls of SCs as known are clean renewable energy sources. Brthr Sabramanian welcome as a 4th collaborator!

I just measured the GO by two probe technique with an electrometer (Keithley, model 2400) and I found it completely insulators

If they request you might send them in supplementary materials. It is encouraged by many journals. However, it is not compulsory as mentioned.

Thank you, 

 That only I am asking because practically it's not possible. So what can be expected.

No, it's unusual. Both are pseudocapacitive materials and can experience redox reactions, but this response  is very much battery-like. It may be caused the electrolyte, particle size of your MnO2 and other experimental parameters. Also, be sure that you didn't oxidize Ti3C2 and formed TiO2. Check our papers on capacitance of Ti3C2.

You can download my papers directly from my website: http://nano.materials.drexel.edu/publications/

Password for PDF files is: nmg

Dear Asma Iqbal Khan,

  Practically both are same. But the origin is different. Ethanol is produced chemically. Bioethanol is from biosources. I Agree with all of the above Especially Rafael.

Sorry, this work was from my final  Master thesis, my research now is on power consumption  monitoring techniques in buildings . However,   Dr Peter Burguess, a PhD fellow, might have some relevant experimental information:

Basic architechture of thin film solar cells is a stacking of a number of functional layers, and, light intensity distribution within devices depends on thin film optics. Therefore, optimization of effective optical constams and thinkness of eacj layer is required to minimize device reflectamce and light absorptance at the position of active layers (ALs)  The most common mistake is neglecting parasitic absorptance of electron- and/or hole-extraction layers.

Taking advantage of forward light scattering that can alter and make effective travel distance longer is also useful in enhancing light harvesting efficiency. Photonic structures for light trapping at ALs and photon recycling are another useful strategy.     

Dear Hang Li 

Greeting

I guess that You can use the conductivity meter in the required range. But I think that the conductivity behavior is almost completely different in the range 100KHz - 10MHz and the measured range 500 MHz - 20 GHz.

Good luck

The easy way: get the manufacturer's data sheet and learn how to read it.

Add wikipedia information to that...

Some more:

Wish you success

I had a discussion with a Ag/AgCl electrode provider before. They mentioned you can use it in alkali solutions but the time should be kept short, several minutes at most. then the electrode should be conditioned in KCl solution again for a long time, minutes to hours.

The problem with using H2SO4 as electrolyte in supercaps is that it is highly corrosive. Hence low cost collectors like stainless steel or nickel can not be used with H2SO4. Companies like NEC which produce H2SO4 based capacitors use conductive carbon but it is also expensive in my opinion. If you want to use low cost and easily available collectors, it would be better to shift to KOH or salt electrolytes (Na2SO4 or Li2SO4). You can then use stainless steel or nickel current collectors with any of them. The operating voltage for aqueous KOH is similar to what it is in H2SO4, up to 0.8 V but with salt electrolytes you can easily polarize the cell up to 1.5 V. Of course your choice of electrolyte should be in accordance with your electrode material. 

good luck

The function of the binder is to hold the materials together in the electrode and to improve adhesion to the current collectors. Different materials might have the mechanical properties suitable for the purpose depending testing conditions for the electrochemical cells - temperature, current level etc.

The binder should also have very little solubility in the electrolyte, otherwise the electrode won't be stable after cell assembly.

Although  PVDF is widely used, there are several reports on using PMMA, polyimides and CMC as binders. In the context of Li-ion batteries, the manufacturers have move out from PVDF in graphite anodes to adopt water-borne electrode fabrication, reducing costs of fabrication and disposal.

You will get sodium metals as cubes. Later you have to cut according to your electrode size.

Here is one link in singapore for Sodium metal

Dear, Prof. Dr. Mal Lushaj,

Thanks for your reply and wishes for Christmas and New Year!

I hope to see you answer in the beginning of 2016!

Best regards,

Iurii Korobeinikov

Dear Peyman,

This is a good book:

Climate Change, Energy, Sustainability and Pavements

by Kasthurirangan Gopalakrishnan et al.

Regards,

Vanessa

Dear Sir,

for soft ferrites we have a Ferromagnetic resonance in a middle frequency region. This is a increasing of µ ´´ . For dielectrics we have no polarisation losses in the low frequency range.

All the best

F. Gräbner

LiBH4 is not an alloy, or an intermetallic. It is a powder, and does decompose easily, and reacts with water.. But, it is not practical to recharge it again. A material that does not melt, but is a practical material to repeatedly refill is nickel lanthanum. Under higher temp and lower pressure, H2 is released as gas.. Under lower temp and higher pressure H2 soaks in.

I should recommend use the smallest one and thin and short pads. Avoid using ground plane under the capacitor and separate it from all metal plates.

Hi, based on my experience, for transition metal hydrides with enthalpy of absorption about 30kJ/mol H2, water as a coolant worked well in keeping the temperature constant during exothermic hydriding process as well during the endothermic dehydriding process. . However, proper designing of the heat and mass transfer aspect is important.

First, I agree with Denis, Higmans "Gasification" is great for gasification understanding.

Since the reaction for water gas shift reaction is an equilibrium reaction, you should search for a possibility to model such reactions. In Aspen or similar flowsheeting software, the "Gibbs-Reactor" could be helpful. It works with minimization of Gibbs enthalpy and should give you acceptable results for the reaction. You might need a heat input or (more likely) removal (reaction enthalpy is around -39.5 kJ/mol at 250°C).

yes, but keep the CPE parameter close to 1. below 0.8 the physical sense is lost

Hi Xingfei,

I think Hugo was also trying to respond you. If so, He is right and I will try to explain a bit more below.

The answer to your question is "No, that is not the case". Both ESR AND R_i are measures of the entire resistance of the cell/system. The electrochemical system is a complex combination of different components each behaving similar to an electrical component (eg., electrode double layer effect is similar to a capacitor and the electrolyte resistance is like a resistor). The overall resistance of the cell for the current flow (both electronic and ionic contributions) can be measured using different techniques such as EIS (from which the ESR can be calculated) or carghe-discharge (from which the R_i can be calculated).

The question intends to find out if theoretically and practically there is any difference between these two and if so, what is that and why it is so.

Moreover, this overall resistance is later used for the calculation of other performance properties of the system such as power density. We need to know which one has to be used there and why.

Normally two electrode setup ,both of the electrode will be your  active materials coated current collector, ,just coat your material on two pt-foil.

Start from 3 electrode setup.then see the difference in the curves.lower discharge time basically due to your materials behavior.

From your doc,

 

its 4.5 cycles,one complete charge-discharge is one cycle. Normally Keep the mass of the material to be more than 1 mg-2mg. so that your output will be more reliable.

 

Keep the Cathodic and anodic time  10sec  is enough.

 

IF you want A/g; Divide current your applying /weight of the active material 

Inhydrothermal synthesis the precursor solubility may be taken as an yardstick to compare the result

It needs a little of background for pure perovskites ABO3[SrTiO3] and doped perovskites.

First considering the SrTiO3 alone.

It has been repored in the literature that in the perovskite SrTiO3( being a nonstoichiometric compound), on heating , there occurs a change in morphology( the grain size, crystal structure etc) . So the number of oxygen vacancies change,i.e. there occurs a change electronic transitions to exhibit wide range of colors, from yellow or light brown to blue-violet and finally black. This effect is called the thermochromism of SrTiO3.[It can be completely reversed by reheating in an oxygen atmosphere or cooling slowly to room temperature from any temperature above 850 C].

Now considering a Ce dopped ABO3[SrTiO3] . It is reported in literature,that

there occurs a decrease in the lattice parameter of doped ABO3 to suggest that a majority of the cerium is Ce(III) substituting on the A-site. B-site substitution would result in an increase in the lattice parameter and A-site substitution by Ce(IV) would not be expected based on the relative ionic radii of Sr(II) and Ce(IV).

In the oxidized samples, there is a significant amount of CeO2 present in the cation stoichiometric sample. Both Ce(III) and Ce(IV) being yellow/ orange yellow( with differing intensities) to make look yellow ( the intensity may vay due to temperature) The A-site deficient sample was single phase.

When the cation stoichiometric sample was sintered for 24 hr., the CeO2 amount decreases significantly and in the A-site deficient sample there is a Ti-rich phase present which being analogous to SrTiO3 and is expected to finally look black.

You yourself told one of the possible answers about doping your compound with different metals such as Mn, Cr etc.

If just improving the conductivity is your aim, you can also do Au-sputtering for this!

Good luck!

There are a lot of materials that are being looked at as many commenters above have indicated. I think many of these are interesting for scientific reasons and I'm all for studying them. However it is my opinion that many of the scientifically interesting materials are not interesting from a pragmatic point of view. That is, various properties including potential negative environmental impact (e.g. Cd-based) and more importantly limited efficiencies and economic considerations mean that they will be unlikely to impact the world on a large scale (not to say they won't find a niche application here or there.) If one wants to change the world on a large scale via this technology it is important to remember that we already know how to make H2 from sunlight at a reasonable efficiency if not cost. PV driven electrolyzers will do the job. So when thinking of new chemistries to explore we must ask ourselves is our goal to gain scientific insight that may one day be applied to make improvements (i.e. change the world indirectly), or do we expect our work to have more direct impact. If it is the latter, then one should be convinced that the material, or more generally the technology, they have in mind has some possibility of being better than known and fieldable options.

To more directly answer your question - yes it is time to consider more and better options.

There are differences between "charge efficiency" (as explained by Christian above) and "energy efficiency" which is more important then "charge efficiency" in the context of energy storage. Energy efficiency is not a simple calculation for batteries, but requires the integration of the potential - time plot for charging and discharging under constant current. Christian is right to indicate that over-potentials are responsible for energy loss, leading to an energy efficiency far smaller than the charge efficiency. In this sense, supercapacitors perform far better than batteries.

I think a possible reason for amorphous (poor crystalline) MO to work better, is due to their large surface area, due to small grain size

Your value is fully consistent with other works, see Fig. 4 of :

but I would not do any extrapolation as the specific capacitance may change dramatically with pore size and redox properties of the carbon surface.

Alain

yes...

Cu for anode

Al for cathode for LIB applications.

Hi Kunal,

There are some straight-forward solid state techniques for producing manganese oxide phase assemblages, including Mn2O3. https://www.researchgate.net/profile/Nancy_Birkner/?ev=hdr_xprf

Best regards,

Nancy

Can also be used as Dye-Sensitized Solar Cells, Electrochemical Energy Storage, Improved Hydrogen Storage, catalysis etc

1)http://onlinelibrary.wiley.com/doi/10.1002/anie.201000659/full

2)http://pubs.acs.org/doi/abs/10.1021/am100951h

3)http://onlinelibrary.wiley.com/doi/10.1002/adma.200304711/abstract

4) http://www.sciencedirect.com/science/article/pii/S1381116903005454

Some news articles:

Regards,

Joachim

We should not forget that if we consider stability we talk about a thermodynamic problem. Initially if the ceria and transition metal precursors are well distributed (e.g. by coprecipitation) we may result in a thermodynamically instable but kinetically stable composition which separates once thermal activation is sufficient and diffusion speed then get high enough. Considering this argument the question of mobility (vapor pressure, diffusion coefficients etc.) is important. From the thermodynamic point of view this does not matter, as it seems the mixture of Nickel oxide and ceria is instable at 1200°C, this is a question of lattice energies and ionic radii.

In XRD there is no indication of formation of a ternary compound or solid solution.

in the system CeO2-NiO, I found this in a thesis published in 2007 at University of Stuttgart by Dr. Nuri Solak : "Interface Stability in Solid Oxide Fuel Cells for Intermediate Temperature Applications." page 87 ff

Our university library has it under following link. However I am sure sure if someone from outside the campus has access.

Everything depends on the current rate which you are using, battery design and frequency (how many cycles). If we are speaking about standard flooded batteries than the higher current rate during cycling (step load change) will lead to longer cycle life time (considering constant Depths of Discharge). Very small current rate can lead to the ageing effect called sulfation which was already mentioned by Holger.

For the VRLA (Valve-Regulated Lead-Acid) batteries the current rate during charging is influencing the COC (Closed Oxygen Cycle) which is an exothermic effect and increases the battery temperature. If your current rate in this case will be too high than you can increase the battery temperature to the level that will harm the battery and decrease its life significantly.

I guess you have to study the ageing effects of the lead-acid batteries a bit. Afterwards you will definitely be able to answer all your questions by yourself.

If you have any further questions dont hesitate to ask.

I can recommend you the following literature:

1) D.Rand et al., „Valve-regulated Lead- Acid Batteries“, 1st Edition, Elsevier, 2004

2) G.Pilatowicz et al. "Simulation of SLI Lead-Acid Batteries for SoC, Aging and

Cranking Capability Prediction in Automotive Applications", JES, 159(9), A1410 (2012)

3) P. Ruetschi, "Aging mechanisms and service life of lead–acid batteries", JPS, 127, 33 (2004)

Hi, u can simulate the compaction process in Autodyn using p-alpha EOS.

The question was aiming at a distinction of alloying and conversion type materials as these terms are commonly used to describe secondary LIB electrode materials (e.g. Chem.Soc.Rev., 2009, 38, 2565–2575).

As i understand both these material types undergo significant structural changes and volume expansion upon lithium uptake and have increased capacity compared to insertion type materials.

So while the discrimination to insertion type materials is evident the distinction between conversion and alloying type material is not clear to me.

If i understand susann correctly the fact that several intermediate phases are formed upon lithium uptake (corresponding to several reaction plateaus) enables one to attribute the term of conversion type material. In the above stated publication the reaction of Sn and Li is however characterized as an alloying type reaction.

Ag/AgCl electrodes are stable in low pH, not too stable in high pH electrolytes for extended times, however. So you should be fine using Ag/AgCl. If in a bind, a Ti or Ta wire would be better to use in aqua regia than Pt as these metals won't corrode as fast.

ethanol steam reforming (SRE)

C2H5OH + H2O=2CO + 4H2

Oxidative steam reforming (OSR), also called autothermal reforming of ethanol:

C2H5OH+2H2O+1/2O2=2CO2+5H2

See (For example): http://www.sciencedirect.com/science/article/pii/S0360319910022238#

I agree with Senthilkumar - reduce the scan speed to say 1 mV/s, and then I guess you will be able to see your reduction peaks. We have made experiments with Ti-oxides which only show extremely broad oxidation/reduction peaks at moderately high scan speeds of around 20 - 50 mV/s, but very sharp and distinct features at 1 mV/s.

I have run into similar issues using porous hydrofillic carbon papers. Usually we found that wrapping self-adhesive Teflon tape around the sample above the exposed area prevented this issue. If this is not enough for your system, you may be able to drop water dispersed Teflon polymer (or colorless nail polish) onto your eletrode above your active area. After drying this makes an impenetrable and inert barrier.

Most DSC apparatus producers (such as NETZSCH) supply an analysis software (e.g. "Proteus") together with the equipment, where you can select the corresponding curve and calculate the the 1. derivative (which is the slope) or even the 2. derivative. I have done this in the Fig. with the NETZSCH software: Blue is the DSC curve (phase transition of potassium sulfate) and red is the 1st derivative, labeled at the axis with DDSC. If you don't have a suitable software available, then export the data with equidistant abscissa (temperature or time) and the slope is then simply the difference between subsequent ordinate (DSC) values, divided by the abscissa step width.

I don´t think that using Ag/AgCl electrode for alkaline electrolytes is a good idea.

While having alkaline electrolyte in working electrode compartment, there was NaCl or KCl in reference electrode compartments. So, the potential of Ag/AgCl electrode should be stable in both cases. But I see two main problems here.

1. There is a membrane potential at the interface between two electrolytes, in the first case 0.1 M NaOH | sat. NaCl and in the second case 0.1 M KOH | 4M KCl. It can be calculated or measured and then taken into account. But I am not sure that it was done.

2. There will be leaking of electrolytes from one compartment to another. The rate of the leaking depends on the electrode and cell constructions, it may be very slow or rather fast. There will be certainly Cl- present in working compartment, and basic pH in RE compartment.

I agree with point 2 made by Mrs. Chamoire above. Any way of heating the material should help you. Higher temperatures or ways of removing the evaporated Sb (heating in vacuum, providing condensation sites) will enhance the effect. If you are talking about removal of Sb from the bulk material and not only the surface (a few 10 nm) temperature will be key because you need to enhance the diffusion within your material. I have 'seen' Sb evaporate from an amorphous material at 600 °C, while there was no effect in the same material when it was polycrystalline (this was done in vacuum). If you have the means, I would suggest to start by heating your material to temperatures between 600 °C and 800 °C in vacuum and see what happens.

If the temperature is too high, you might actually crack the bond between Co and Sb and end up with a material that is light on Sb though.

It has been reported the measurement of thermal conductivity by Modulated Temperature Differential Scanning Calorimetry (MTDSC), according to the following ASTM test:

ASTM, "Standard Test Method for Thermal Conductivity and Thermal Diffusivity by Modulated Temperature Differential Scanning Calorimetry", Standard Designation: E 1952 – 01.

The process described was covered by a patent: S. M. Marcus and M. Reading, U. S. Patent 5 335 993, 1994, held by TA Instruments, Inc., which seems to be now expired.

A related paper, entitled "Precision and Bias of the ASTM Test E1952 for Thermal Conductivity by Modulated Temperature DSC", authored by Roger L. Blaine and R. Bruce Cassel (both from TA Instruments), was presented at the 29th Conference of the North American Thermal Analysis Society, 24-26 September 2001.

Another reference for the method previously stated is: S. M. Markus and R. L. Blaine, Thermochimica Acta, 1994, 243, 231-239.

An alternative approach, also with MTDSC, was proposed by S. L. Simon, J. W. Sobieski and G. B. McKenna, Proceedings of the 26th Conference of the North American Thermal Analysis Society, K. R. Williams (Ed.), 1998, 129-133 (available from http://www.natasinfo.org/publications/).

It is, in principle, possible to adapt an existing a DSC system for use with the MTDSC technique, but that would require significant development time and expertise in data acquisition and control systems. It is therefore advisable to ask for the possible availability of a ready-to-use company solution, from the same company that supplied your system.

Alternative methods, developed for power-compensated DSC, are addressed by the following patents:

Mikhail Merzliakov, Christoph Schick (PerkinElmer Instruments LLC), Method for measuring absolute value of thermal conductivity, US 6,497,509 B2, Dec. 24 2002; idem (PerkinElmer Health Sciences, Inc.) EP 1 402 249 B1, 05.05.2010.

Victor F. Mazzio (Eastman Kodak Company), Method for determining thermal conductivity incorporating differential scanning calorimetry, US 5,099,441, Mar. 24 1992.