A great idea came out !

I've carried out my Masters Degree Thesis at Cranfield University in the United Kingdom. After about 3 months spent studying the essential theory on the topic of my thesis, which was focused on the global warming concern and on the study of novel technologies to reduce CO2 emissions in the atmosphere. - Gramatically, I think this would make more sense as one sentence. I would write:

I've carried out my Masters Degree thesis at Cranfield University in the United Kingdom, after about 3 months spent studying the essential theory on the topic of my thesis (which was focused on the global warming concern and on the study of novel technologies to reduce CO2 emissions in the atmosphere).

However I needed to start with the experimental work because my time at Cranfield was limited and I wanted to complete everything before going back to Italy. Nevertheless, my supervisors did not know what actually I should have done (I'd say "what I should have actually done"). So I've decided to take a my own decision about what and how the experimental work had to be carried out.
Reading a lot of scientific papers,one day, I found out that in literature there were no studies about application of a particular compound such as calcium oxide concerning the technology I was studying, although it had all the requirements to be used. At that point, immediately I decided to talk to my supervisor about the idea of doing experiments using that kind of compound and luckily he was so glad to support me to find out more about the opportunity to carry out that kind of work.I approached that challange with enthusiasm and I was sure to do it well.In the end it was the best choice since I successfully completed my work at Cranfield with a positive feedback of from all the people in my group research research group and I also realized a dream of writing, along with my supervisors, a scientific paper submitted to the scientific journal “Energy Technology “ totally based on the work I did there and I am so proud of this.