You may try sputter coating a thin layer of Ti metal onto FTO, and then oxidize the Ti at about 450 C to get a TiO2 top layer. Now you apply your coating on to this oxidized layer.

You can also try very slow heating and cooling rates (2 C/min) to control the spalling off of the layers during calcination.

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Using spin coating technique,,

Dear Haidar,

Try with sol gel spin coating method. During the preparation of your solution (sol -> gel : process). You should add some ethylène glycol (EG, DEG or PEG). it is a polymerization agent which helps in improving the viscosity of the solution and hence the adherence of your thin film to substrate under gelification, drying and annealing.

Dear Haidar,

I recommend subjecting the FTO substrate to UV-ozone cleaning procedure prior to sol gel spin-coating deposition.

Thanks all, I am wondering if there is a procedure detailing the precursors needed to make the sol-gel solution of TiO2.

Of course, take a look to the table (image) I sent to you. Good luck.

Dear Haidar,

you can find a simple procedure here, where a sol-gel route is followed to obtain a thin (around 40 nm-thick) and highly transparent TiO2 compact layer onto the FTO substrate:

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