In wet chemistry methods the presence of growth directing agents, lets said, species that would adsorb preferentially onto some crystal surfaces for example iodine ions, surfactants as CTAB and so on, would lead to different morphologies.

when u change the reaction parameter like pH or temp will change the morphology of the Nano particle. then change in reduction agent also change the morphology of particular Nano particle. the best method for change the morphology is doping as per my knowledge doping is the best way to change the morphology

You can use Hydrothermal method, Co-precipitation method with controlled pH for better morphology and good pore volume with high surface area.

Thank you for the answers. The conclusion is, by changing the growth directing agents, annealing temperature , pH and by increasing or decreasing the concentration of growth directing agent we may change the morphology of the nano particles.( And according to my knowledge doping is mainly used to decrease the band gap).

First of all you should be specific with material,

To give a generalized approach is very difficult becuase morpholgy or surface area will depend upon your synthesis conditions, your precursors, your method of synthesis and if you are making oxides from any pre synthesised hydroxide, carbonate or oxalate etc than annelaing temperature will play a cruical role in definnig surface area and pore volume of your material.

To give you an idea I used hydrothermal synthesis of metal carbonates to have metal oxides after annealing. In the hydrothermal synthesis the kinetics of reaction was strongly dependent on hydrothermal reaction temperature and I was able to alter morpholgies of carbonate by changing hydrothermal reaction temperature.....

Plz take a look at this paper for another example of dependece of syntheisi conditions on your product morpholgy and surface area, pore volume

Article Carbon-free cobalt oxide cathodes with tunable nanoarchitect...

Thank you sir for the suggestion. I will read the paper which you suggested.

Its a generic question you raised, I can give you a general answer in this regards:

Morphology depends upon the Synthesis process i mean (Top-Down or Bottom-Up) process you apply gives you the specific morphology of nanoparticles.

Eg. Chemical synthesis process solvent and precursor salt influence morphology along with this other parameter of the synthesis also govern like pH , temperature, annealing etc.

Particles size directly govern the high surface area of nanoparticles , apart from this nature of the structure like 1-D, 2-D affect surface area of nanoparticles.

Porosity of surface is an overall outcome of your synthesis process.

Thank you for the suggestion sir.

By using different suitable organic solvents in proper proportions OR by changing the pH of solution can synthesize different morphology of nanomaterials. Synthesis of 1D nanomaterials gives more surface area. It depends on temperature and precursors used.

some of the articles below related to different morphology.

Journal of ELECTRONIC MATERIALS, Vol. 42, No. 6, 2013

CrystEngComm, 2012, 14, 1920

J. AM. CHEM. SOC. 2006, 128, 1466-1467

Chem. Mater. 2014, 26, 123−133

J. Braz. Chem. Soc., Vol. 24, No. 10, 1662-1668, 2013.

International Journal of Materials, Mechanics and Manufacturing, Vol. 1, No. 4, November 2013

Thank you

Thank you

What methods can i used for the modification of morphorlogy of nanomaterials