Catalyst - Science topic

Azita Etminan You don't mention the concentration of Ni you require in the final material but the usual route to produce catalysts of this nature with Ni in the 1 - 5 wt% typically is by impregnation of the base material (e.g. Ni/SiO₂, Ni/CaCO₃ etc) and then subsequent reduction. Simple precipitation of Ni salts with base produces Ni(OH)₂ which will calcine to NiO and not Ni.

The preferred route would need a knowledge of the pore volume of the base (do you really mean Ce₂O₃ and not CeO₂?). This knowledge can be obtained by simple titration of a known amount of the dry material or via porosimetry. A solution of the appropriate Ni precursor (nitrate would always be preferred over chloride) would be used to just saturate the pores and produce an x wt% Ni in the final powder. Reduction would then take place (in the dry with H₂; in the wet my preferred reductant would be 5 or 10% hydrazine hydrate as the only products are water and N₂). This would then produce Ni in the required concentration on the substrate. A further drying process would be needed for wet reduction. I'd avoid borohydride reduction as this always leaves intractable B in the matrix.

Petrobras, a major state-owned oil company in Brazil, has indeed played a significant role as a catalyst in developing various markets, both within Brazil and internationally, suco as::

1. Offshore Oil Exploration and Production: One of the most notable areas where Petrobras has been a catalyst is in deep-water and ultra-deep-water oil exploration and production. The company's investments and technological advancements in this field have not only bolstered Brazil's oil industry but have also led to the development of a specialized market for deep-sea exploration technology and services.

2. Local Content Development: Petrobras has often been involved in initiatives that require suppliers to use a certain percentage of local content. This has helped develop local industries in Brazil, particularly in the oil and gas supply chain, fostering the growth of local businesses, manufacturing, and services.

3. Renewable Energy Sector: Although primarily an oil company, Petrobras has also ventured into renewable energy sources, such as biofuels, wind, and solar energy. These ventures have helped stimulate the renewable energy market in Brazil, encouraging innovation and investment in these areas.

4. Shipbuilding Industry: In an effort to renew its fleet, Petrobras initiated programs that required new ships to be built in Brazil, which led to a revival of the Brazilian shipbuilding industry.

You need to train a regression neural network with your experimental data. Then keep the trained neural network in your workspace. You can use this trained model as an objective function simply by using the function handle. Say the name of the trained model is 'trainednet'. The objective function can then be defined obj_func = predict(trainednet,x). You can use it as objective function by calling @obj_func

Ghada Aljaber Thank you for your question. This is relatively simple to answer with a grasp of chemistry but does need some care with the calculations.

So, you want to end with 3wt% Co in NiFe₂O₄ – that is, 0.03 g Co plus 0.97 g NiFe₂O₄ for a gram of final material. OK, so how do we get there? Consider NiFe₂O₄ as an equal ‘mix’ of NiO plus Fe₂O₃. Let’s consider getting to a gram of the doped material as then if we want to make more then we simply have to multiply the amounts of the starting [precursors by the appropriate factor.

The MW of the precursors and the decomposition route are key:

• Fe(NO₃)₃.9H₂O MW 403.999 g/mol gives rise to Fe₂O₃ (MW 159.6882 g/mol) on decomposition. We note that we’d need 2 moles of the nonahydrate to give rise to 1 mole of the oxide

• Ni(NO₃)₂.6H₂O MW 290.79 g/mol gives rise to NiO (MW 74.6928 g/mol) on decomposition

• Co(NO₃)₂·6H₂O MW 291.03 g/mol gives rise to CoO (MW 74.93 g/mol) on decomposition. You’re specifying Co (atomic mass 58.93) not CoO

• NiFe₂O₄ MW 234.381 g/mol. In 1 g of this material, we’d have 159.6882/234.381 g of Fe₂O₃ and 74.6928/234.381 g of NiO. For 0.97 g of NiFe₂O₄ we’d need 0.97*(159.6882/234.381) g of Fe₂O₃ and 0.97*(74.6928/234.381) g of NiO

Let’s start with the dopant (Co) first. To get 0.03 g of cobalt would require 0.03*(74.93/58.93) g of CoO which would be produced from a multiplier of (291.03/74.93) g of the hexanitrate. Thus, we’d need 0.03*(74.93/58.93)*(291.03/74.93) g of the precursor hexanitrate to lead to 0.03 g of Co

Now, the iron nonahydrate. (2 X 403.999) of this gives rise to 159.6882 g of Fe₂O₃, so we need (2 X 403.999)/159.6882 g of the nonahydrate to give rise to 1 g Fe₂O₃. We actually require 0.97*(159.6882/234.381) g of Fe2O3 equivalent in the final product. So our starting nonahydrate would be 0.97*(159.6882/234.381)*[(2*403.999)/159.6882] g of this precursor

By a similar argument, for the NiO equivalent, then to get 0.97*(74.6928/234.381) g of NiO requires a multiplier of (290.79/74.6928) of the hexahydrate. That is (290.79/74.6928)*0.97*(74.6928/234.381) of the nickel nitrate hexahydrate for a gram of the final NiFe₂O₄.

You need to check my math and that I haven’t made a typo (or several typos) and also that I have the molecular masses of the compounds correct. I’ll leave you to multiply out the final values and check that they’ll make 1 g of final material. For larger amounts you can multiply by the appropriate factor, as I said earlier.

You definitely have a leak of air into your set up not necessarily in GC. As a result, oxygen reduction reaction compete with proton reduction. Do a control experiment with everything in your system, but without a catalyst. You should not see any O2/N2 peaks.

Jürgen Wintner Thank you very much!

Barry Turner

I clicked on the LINK in the above Call for Chapters. Here is a copy-and-paste of the template, which will give you an idea of the required elements; however, it looks like you will have to have the original form to submit.

Also, the original version shows yellow highlighting for most of the bold face rubrics, as well as some of the explanatory regular font guidelines.

[Chapter  Author 1: Name and Affiliation]

[Chapter Author 1 Email address]

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* Add / Delete as necessary

Author/s Biography/ies:

[Please insert name as it appears on the Chapter, Affiliation and Country. Individual Biographies should be up to (and no more than) 150 words which can include detail regarding other books published in the field]

Insert abstract

(Please supply up to 6 keywords for your Chapter)

1. ..

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Insert the chapter here (including any introduction)

· If any parts of your chapter have already been published, please ensure that you have a permission to include the text from the Copyright owners and include “This chapter/parts of this chapter have been published in……” in your introduction.

· If you are adding Tables/Figs/Pictures/Illustrations, please indicate the place they go in the text by inserting the following:

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(or attach them in separate documents)

Best wishes,

Nancy Ann Watanabe

Hello Dr. Henrik Rasmus Andersen,

thanks for your reply. The experiments were finished in June. Currently, I don't have any questions. The reason behind the issue was the evaporation of some water in the organic dye. During three hours, the experiment was performed under light, the light makes heat. As a result, the final solution lost a significant amount of water, increasing the final TOC. Sorry for the delayed response.

Best regards.

In my opinion, the poor fixation of the BiOBr photocatalyst to the nickel substrate is due to two reasons: too weak adhesion of oxybromide to nickel (there are no functional groups capable to form chemical bonds between these components) and an excessively high difference in the thermal expansion coefficient of nickel and oxybromide. Therefore, three approaches could be tested (in order of their feasibility):

- deposit an intermediate buffer layer, for example, made of metallic bismuth, onto the surface of the nickel substrate, then apply BiOBr to it;

- distribute BiOBr particles in a binder that does not impair the functioning of the photocatalyst (for example, like magnesium cement or a porous photo stable polymer);

- chemically modify the nickel surface, for example, by treatment it in passivating media.

a spark of light perhaps....

JAS Claude.ai LLM (Summary, Cut & Paste)

define how to quantify, qualify and subjectify spirit based on the following: https://www.researchgate.net/post/Is\\_SPRT\\_real\\_Can\\_it\\_be\\_mass\\_produced\\_for\\_a\\_given\\_purpose

Claude can't visit links. Responses may contain hallucination.

JA

I do not have a definitive way to quantify, qualify or subjectify spirit, as it is an abstract concept. However, here are some perspectives on how one could approach analyzing spirit:

Quantify:

Qualify:

Subjectify:

The researchgate post seems to be discussing SPRT (Spirit Possession Research Training) which involves training mediums. I do not have enough information to determine if SPRT can be mass produced for a specific purpose. Examining spirit possession phenomena requires an interdisciplinary approach including anthropological, psychological and neurological perspectives. More research would be needed to evaluate the viability of standardizing spiritual mediumship training. Overall, analyzing something as abstract as spirit requires combining objective measures with subjective perspectives and meaning.

Very strange--please check your experimental setup and your analytical methods?

Thank you

Dear Hamza Naeem , what I wrote is to explain how to build a Tafel plot, because what you show is a polarization curve. You should analyze your data as a Tafel plot based on what is described for HER.

Check this:

and this:

Regards!

If your sample is nano-powder, a small amount of your catalyst nano-powder sample ( one or two grains) is dispersed in ethanol (10 ml). Every step is taken very carefully to avoid the contamination. Place a droplet of the catalyst nano-powder suspension on the TEM grid using a glass dropper (cleaned and washed) then allow the ethanol to evaporate (minimum 24 hours). after completing this protocol sample grid insert the sample holder and insert the TEM.

Using a two electrode setup, you may measure the impedance without a reference electrode. You'll need a stable reference electrode if you simply want to conduct your research on working electrodes. Reference electrode is required for electrochemical cell measurement accuracy and constant ground voltage.

Troy Warry

You are right and wrong in your research and questions. The decomposition of methylene blue can occur without a catalytic agent. All catalysts reduce the activation energy of a reaction and therefore speed up the reaction. Reviewers of some paid journals may pass up an article with no experience, that is, without a catalyst for their profit. I wrote about such citations in my post.

Titanium dioxide has a number of allotropic forms: anatase, rutile, mixtures of them and various catalysts. It is necessary to check their structure and particle size. The smaller the nanoparticle size, the better the catalyst.

Jorge Arce Castro Thank you. But I have a gas flow!

Pramod Gawal

Zeta potential is a parameter that can indicate the stability of a disperse system to aggregation of catalyst nanoparticles or sedimentation. It depends on the composition of the dispersed system, pH, electrolytes... If the dispersed system is stable, it will work well as a photocatalytic catalyst. For your disperse system, it is necessary to experimentally determine the zeta potential.

Hi Mohini Tayade,

A catalyst is a substance that can be characterized as homogeneous which is in the same phase as the reactants liquid or gas, and heterogeneous, or enzymatic that are not in the same phase as the reactants. When catalysts are added to a reaction, it increase the reaction rate without getting consumed in the process, in addition to accelerating a reaction by reducing the activation energy or changing the reaction mechanism, so, it prevents agglomeration when synthesizing the nanomaterial.

Thank you!

Dear Doctor

Go To

"Conclusions

In this work, an overview of the current challenges in catalyst development for PEM-WEs is given. Due to the limited availability of iridium which is currently the only viable option as an oxygen evolution reaction (OER) catalyst, a reduction of the iridium loading from currently » 2 mgIr cm–2 to only » 0.05 mgIr cm–2, i.e., by a factor of 40 is required in order to enable a large-scale application of PEM-WEs. While the activity of current Ir-based catalysts would generally be sufficient to achieve the proposed target values for Ir loading at only minor performance losses (only 4 % increase of the cell energy consumption to produce 1 kg of H2), the development of catalyst structures with a much lower iridium packing density compared to current catalyst materials is absolutely required to realize homogeneous catalyst layers at very low Ir loadings. Several pathways to develop such high-structured catalysts (i.e., catalysts with a low iridium packing density) have been proposed in the literature. Here we show first results that demonstrate that for a high-structured catalyst a reduction of the Ir loading by a factor » 8 is possible, even with a slightly improved efficiency compared to a commercial Benchmark catalyst. With this new OER catalyst developed by Heraeus, the Ir-specific power density at an efficiency of 70%LHV (≡ 1.79 V) of » 0.05 gIr kW–1 can be achieved at > 3 A cm–2 with a 50 mm thick Nafion membrane. To make the development of new catalyst materials more efficient, activity and durability screening methods are required to allow a fast identification of promising materials. The rotating disk electrode (RDE) method which is commonly used to evaluate catalyst performance is shown to be suitable for a characterization of catalyst activity, while OER catalyst stability tests are affected by measurement artefacts and, hence, do not give meaningful information about catalyst lifetime. Consequently, accelerated stress tests (AST) on the membrane electrode assembly (MEA) level are required to evaluate catalyst stability at realistic operating conditions. A test protocol simulating an intermittent power supply by cycling between open circuit voltage (OCV) and operating potentials is presented as an example for such an AST. Here, the recurring transition between reducing and oxidizing conditions leads to the dissolution of Ir and the formation of a contact resistance between electrode and PTL resulting in a much higher degradation rate compared to a reference experiment without OCV periods. The information gained from this experiment helps to identify harmful operating conditions that need to be avoided in real PEM-WE systems."

Sunil V D

.FeCl3 is not oxidized by atmospheric oxygen. However, in your reaction it will act as a weak oxidizing agent at the double bonds to allow polymerization to occur. Without an inert gas, the oxidation of thiophene by atmospheric oxygen can proceed through sulfur, which will lead to a deterioration in the polymerization reaction.

Dear Aaditya

Then main important feature of Pt, by which makes it an ideal option, is the fact that Pt is a noble metal. For electrodeposition studies in acidic media, you have no concern about the possible dissolution of Pt. Therefore, you can focus on the mechanism of hydrogen evolution. I think you can also use other noble metals such as Pd, Ag, etc..

Hello Mona,

You may buy it online. You may make an inquiry at Alfa Chemistry, they offer kinds of good-quality products.

Hai Dear Atiyeh Karkhaneh Jafary, I hope this will help to you

The proper potential for photocurrent analysis depends on the type of catalysis and the materials involved. In general, the potential should be chosen so that the photoexcited electrons can be injected into the conduction band of the semiconductor, but not so high that they are immediately lost to recombination. The exact potential will need to be determined experimentally for each system.

For example, in the case of photoelectrochemical water splitting, the potential should be chosen so that the photoexcited electrons can be injected into the conduction band of the semiconductor, but not so high that they are immediately lost to recombination with the holes in the valence band. The potential will also need to be high enough to oxidize water, but not so high that it causes the semiconductor to degrade.

The potential required for photocurrent analysis can also change depending on the catalyst used. For example, in the case of the oxygen evolution reaction, the potential required for a ruthenium catalyst is different from the potential required for a cobalt catalyst.

Dear Snahasish Bhowmik There are various reasons for detaching the Cat from the electrode surface, such as high positive/negative voltage, bubbling etc. Also, it depends on ink film dispersion on the electrode surface due to different physisorption properties of the material and ionomer ratio. A possible solution could be, that you should know what is your exact potential window, try different ionomer/catalyst ratios, and try to make a very uniform thin film.

Following reference could be more useful to optimize the ink film formation.

Edward Chandler What does the XRD pattern of the support carbon black look like? That is, with no metal loading.

AcOH+Pyridine -> pyridinium salt(py+) + NaH2PO2 -> Py+H2PO2- are stable source of hydrogen in aqueous reaction medium.

pl share the full paper sir.

V. A. Borisov

What studies? Refs, plz

Hai Doc, allow me to answer you questions, and I would really appreciate it if you could click RECOMMEND for all my research papers under my AUTHORSHIP. Below are my answers :

In my view, it should definitely be possible to model a monolith (honeycomb) reactor in both Aspen Plus and Aspen Hysys. Here are a few key points:

Both simulators contain models for catalytic fixed-bed reactors that could reasonably represent the monolith structure. The monolith would act as the static catalyst packing.

Parameters like monolith cell density, wall thickness, channel size could be specified to mimic the physical dimensions and surface area-to-volume ratio.

Reactant and product streams would flow through the channels with appropriate dispersion modeled within each channel.

Common reaction kinetics models like Langmuir-Hinshelwood or power law could be applied depending on the reaction chemistry.

Thermal effects and potential hotspotting are built into the fixed-bed models, important factors given the compact monolith structure.

Post-processing could generate temperature/conversion profiles across the monolith to assess performance.

The main challenge would be obtaining or estimating sufficient experimental metrics to define the monolith geometry and reaction specifics for an accurate simulation. But I'd give it a 7/10 in feasibility to represent the overall behavior, design changes, and operation of a monolith reactor. Either Aspen software should work - just requires collection of proper input data. Let me know if any other questions!

Syadza Firdausiah

A good catalyst should have a large specific surface area. Therefore, synthesize a catalyst from nanoparticles. You can find synthesis methods on the Internet by typing the words "synthesis of iron nanoparticles".

Hi Kuldeep,

This reference looks relevant (from a search of Google Scholar):

I'd say do a forward search of this to see what has cited it since.

This is an interesting area!

-Kyle

Viscosity is an intrinsical property of the DES, so maybe consider the idea of replacing your DES with another one having power viscosity. Personally, I would not add any solvent: if you used something nonpolar (e.g. DCM) you would obtain a biphasic mixture, while if you added something polar (e.g. water, DMF, DMSO), you would destroy the hydrogen bond network, so to disrupt the unique structure of the eutectic mixture (assuming that you are using a real Deep EUTECTIC solvent)

The hydrogen pretreatment of many noble metal catalysts for oxidising carbon monoxide (CO) is a well-known process that enhances catalytic activity. The reasons for this are multifaceted and include changes to the catalyst surface, oxidation state, and active site accessibility. Here's a breakdown of why hydrogen reduction might lead to an increase in the activity of a CO oxidation catalyst:

In summary, hydrogen pretreatment is not a one-size-fits-all method, and the actual mechanism can depend on the specific catalyst, support, reaction conditions, and other factors. It often requires careful characterization and understanding of the catalyst system to utilize hydrogen pretreatment effectively. Research in this area continues, and modern surface science and catalysis techniques are providing more insights into these complex processes.

Is this older discussion helpful?

It is volunteer platform. If you know answer you can write answer

Constrained Minima Hopping method may solve your question. For detailed information, you can refer to the following link: https://wiki.fysik.dtu.dk/ase/tutorials/minimahopping/minimahopping.html.

Dear Narayanan Subramanian, DMC is rather an old catalyst that is largely investigated. Please have a look at the following links. My Regards

Dear Sherzod,

Currently, research focuses on ester synthesis using enzymes and more specifically with immobilized or non-immobilized lipases. does that answer your question?

Homogeneous catalysis of hydroformylation reactions is an area associated with hetero binuclear active sites - for example see J. Am. Chem. Soc. 2003, 125, 18, 5540–5548 https://doi.org/10.1021/ja029499i .

Thank you for your contribution Dr. Alexandru Ioan , what worries me is that if addiction is created, it open the door for a new human need, from one point of view it is a development with the merits of (Economic Growth-Improved Quality of Life-Technological Advancement), from the other point of view it is (Consumer Manipulation-Overconsumption and Waste-Shifting Priorities-Dependency)!

ensuring that the benefits outweigh the potential drawbacks and that ethical considerations are taken into account is crucial when creating a human need!

Both the reacting ions, nitrophenolate and borohydride ions, are negatively charged. So, the electrostatic kinetic barrier prevents the reaction between these anions. So a catalyst is necessary to initiate the reaction

Use response surface models from Design expert or Minitab and navigate through the numerical optimization for the optimum parameters.

[Figure example missing right now.]

Are you looking for something like this?

@ Shikhasmita, common solvents used for TEM analysis are acetone or ethanol, often followed by propylene oxide.

Amir Mostashari

From TEOS, a silica hydrogel is obtained by hydrolysis. After drying and removing water, porous silicon is obtained. GO acts as an inert filler in your composition. Therefore, with an increase in TEOS, the porosity of the composition increases.

EDS analysis provides information on the composition of a surface about 5 nm thick. Therefore, it is impossible to judge the composition of the sample as a whole. There is little oxygen in the composition of GO and you do not know it. In the composition of silicon oxide, too. It is in a mesh, polymer, and not in the form of SiO2.

It seems that your flowsheet has a dedicated de-oxo converter for trace O2 removal from the H2 stream. I presume that this will use commercially available de-oxo catalysts. Therefore, consult with the catalyst suppliers concerning operating condition ranges versus conversion efficiency. Surely you ask for catalyst performance projections when you as for quotations!

gives a fairly recent review of computational methods, based on density functional theory, for analysing the electronic structure and performance of single-atom catalysts.

M. Karthikeyan

The catalyst lowers the Gibbs activation energy of the reaction and therefore increases the rate of the reaction.

The Tafel slope is how much you have to increase the overpotencial to increase the reaction rate by a factor of ten (dec). When you change your potential by 1 volt, the Gibbs activation energy of the reaction will change by 1 eV per electron transferred, but the activation energy will only change by a fraction of that, and that fraction determines the Tafel slope.

You can choose the high-performing catalyst by considering overpotential and Tafel slope alone.

See the Physical Chemistry Student's Guide and our article

I appreciate your response Aurobindo Patnaik

I am going to modify the zeolite 13X using calcium hydroxide(5wt%) and based on my research wet impregnation is the optimum method. I have to mention the zeolite is not in powder form, it's granulated(mesh 30-50).

If you have any information in this field or some instructions on this method, please let me know.

Thank you in advance for you help

Do you mean homogeneous or heterogeneous? I think starting with just Copper metal is good. If you have a carbon electrode, you could electrodeposit Cu(0) from copper salts on it too.

The Tafel slope can then be obtained from the linear region of the polarization curve at high overpotentials

The occupied d-orbitals are actually lower in energy than the s-orbitals that belong to the highest energy level.

https://socratic.org/questions/what-is-the-electron-configuration-of-ag

How to compare the activities of two different water oxidation catalysts is not solved problem. What are the criteria? In most of publications the dioxygen formation is not proved. First, you need to prove that dioxigen is formed.

In this case you have to consider the total volume of the resulting catalyst/alumina bed

Dr. Yuri V Geletii, Thank you Yurii V Geletii so much for sharing the info and will looking into more about the general answer and other specifications about catalyst that I am going to use.

Practices such as using cover crops, applying manure and compost, rotating crops, and controlling erosion for soil conservation, can maintain or increase soil organic matter. Other practices, especially plowing, tilling and cultivating, can decrease the amount of organic matter in the soil. In order to minimize crop damage created by pests and maintain soil health, farmers apply different protection measures: crop rotation, crop isolation, tillage, mixed farming, proper planting time, cover crop and barriers, mulching and green manure, chemical, and natural soil and plant. There are several ways of improving aggregate stability: Retain surface cover to slow down the rate of wetting and lessen raindrop impact. Minimize tillage and traffic that damages existing soil structure. Increase root and biological activity by maintaining healthy vegetation growth. Improving soil management through practices like cover cropping and optimizing grazing patterns can remove carbon dioxide from the atmosphere by increasing carbon uptake and reducing carbon losses from agricultural soils.Land uses and management that reduce carbon inputs or increase losses compared to natural vegetation result in reductions in SOC over time, creating a soil carbon deficit relative to the levels of carbon that previously existed in the soil. Rainfall and temperature have by far the strongest influence on soil organic matter levels. Soil organic matter content is usually higher where rainfall is higher and temperatures are cooler.

Ramin Javahershenas Thanks for your suggestions. We tried adding sodium carbonate to reaction mixture but still we didn't obtained vanillyl alcohol.

We are using Ni-Cu catalyst on graphene oxide. We will be grateful if you could be specific with quantity of sodium carbonate and optimum hydrogen pressure and temperature that needs to be maintained.

Dear Ansari,

I am not sure what you mean with membrane structure, but if heating is no option for preparation, try using high vacuum alone. But you have to exclude (carbon) contamination from TEM. Otherwise the operator will be angry because usage of TEM will be delayed only by this contamination.

You could also try freeze-drying.

The most sophisticated method would by kryo-TEM, but I do not know about preparation for these

Hope this helps

Lucas Warmuth

Yes, there are a few methods that can increase the N-methylation response of aliphatic amines. One method is to use a stronger methylating agent, such as dimethyl sulfate or methyl iodide, to facilitate the reaction. Another method is to use a higher temperature during the reaction, which can increase the rate of the reaction and improve the yield. Additionally, using a higher concentration of the amine substrate can also improve the reaction efficiency. However, it is important to note that these methods may also increase the risks associated with the reaction, such as toxicity and safety hazards, and should only be attempted by trained professionals in a safe laboratory setting.

It would be best if you elaborate- on what you would do and what products would like to get. There are excellent publications are available in open domain

It is not easy to recover PdP₄ (P = PPh₃) from the catalytic mixture. In solution on most of the occasion, it turns into PdP₂, a 14 electron species (by dissociating two Pd-P bonds and PPh3 will be in solution) to get ready for oxidation addition to form Pd^II square planar complex and catalytic process continued until elimination of desired coupled product takes place. It is highly unlikely to anticipate the formation of PdP4 after this process. After elimination, 14electron species (active catalyst) is ready for next cycle.

If you try to isolate, you may end isolating only oxidatively added Pd^II square planar complex.

Best wishes

Balakrishna

The phase transition from bimetallic catalyst to spinel phase can have a significant impact on the textural acidic properties of the catalyst. The textural acidic properties refer to the acidity of the catalyst surface, which is an important factor in determining its catalytic activity.

During the phase transition, the crystal structure of the catalyst changes from a bimetallic structure to a spinel structure. This can result in changes in the coordination and oxidation states of the metal ions, which can affect the acidic properties of the catalyst.

In general, spinel phases tend to have higher acidity compared to bimetallic phases, due to the presence of oxygen vacancies and/or cation vacancies in the crystal structure. These vacancies can create Lewis acid sites, which can interact with adsorbates and promote catalytic reactions.

However, the exact effect of the phase transition on the textural acidic properties of the catalyst will depend on various factors, such as the specific metals involved, the synthesis method, and the calcination temperature. For example, the size and distribution of the metal particles can also influence the textural acidic properties.

In summary, the phase transition from bimetallic catalyst to spinel phase can increase the textural acidic properties of the catalyst, but the magnitude of this effect will depend on the specific details of the system.

As a PhD Scholar, you should focus on the global challenges associated with climate change, waste recycling (recovery) and its contribution to circular economy. The Environmental challenges in your country/community and its negative consequences on health and economic among others.

Qasim Qayyum Kashif ok thank you

Paweł P. Sobecki Thank you very much!

Dear Qasim Qayyum Kashif , have you ever read about pKa? What is the second pKa of H2O2? The mechanism you have suggested for H2O2 decomposition is wrong without any doubt. If you teach the people (e.g. by answering questions), you should be an expert or at least have basic knowledge in the area.

The mechanism of H2O2 decomposition is very well studied and described in many text books.

I apologize for a very straightforward language. I'm tired to read answers based on insufficient knowledge.

Dear Shahid Zaman,

I want to ask a question in similar direction. I have a two electrode setup flow cell for co2 electroreduction. How can I control the potential at working electrode (cathode) vs RHE? Because I read in the literature that people report potential vs RHE. How can I measure that in two electrode setup?

Best,

Dear Jurgen,

Thank you for bringing the error in the question to my attention

The following details are corrected

1) 0.0573 g Catalyst was taken for analysis

2) H2 gas desorption is 8.740 mmol/g of catalyst

3) wt % of metal in the catalyst (0.97%)

kindly let me know if the following information is not enough to calculate the dispersion %.

One is using 5 or 10 % Pd on carbon to conduct hydrogenation of a number of functional groups in substances, then other factors are the solvent; the hydrogen pressure one provides to the Parr apparatus (and conduct the shaking in a constant way). One can calculate the amount but Pd/C is a catalyst which means that after reaction it will be present in almost quantitative way. I would advise to check the literature and take into account the amount of Pd/C which is reasonable. At the limit if you would use equal millimoles Pd/C and substrate, your reaction might not proceed quicker. In making 100 substances during my Ph.D I have always used say 50-100 mg for 20-25 g of substrate (I NEVER calculated millimoles). One reaction I recall is the conversion of 4-nitro-anthranilic acid to 4-amino-anthranilic acid with Pd/C in ethanol overnight at 3 bar hydrogen overnight.

The oxygen storage/release rate of ceria-based compounds can vary depending on the specific composition of the material, the reaction conditions, and the nature of the catalytic process. In general, ceria-based compounds are known to exhibit high oxygen storage capacity and rapid oxygen release rates, which can be beneficial for catalytic processes under lean/rich conditions. However, the specific rate of oxygen storage/release will depend on the specific details of the system under consideration.

The reason of differences in photocatalytic performance is the changes of electronic structure. Each atom has different electron configuration, electron negativity and atomic/ionic radius. Therefore, each dopant state will be located depending on the atom. Various electronic structure = differences in light absorption and recombination rate, so these effects will cause differences in photocatalytic activity.

Moreover, the presence of new atoms may influence on the morphology of the final photocatalyst, which is also a important factor, because it affects water adsorption properties and also the photocatalytic activity.

I hope this answer is sufficient for you. The subject is extensive, so I am not sure if this is an answer you are looking for.

it can be done with various techniques.

like you can run multiple Cyclic voltammetry scan and the check the ip, or you can run UV-Vis before and after the reaction, or Control potential electrolysis (bulk electrolysis) ... so on..