Study of the responses of the membrane based on FePO4 : Ag2S : PTFE = 1:1:2 with the addition of Al2O3 nanoparicles at pH = 1 and pH = 1,5 : bachelor thesis

Potenciometrijskom metodom izvršeno je ispitivanje novoizrađenih senzora, tj. membranskih elektroda na bazi željezovog(III) fosfata, srebrovog sulfida uz dodatak politetrafluoretilena koji je bitan za kompaktnost smjese i otpornost prema jakim kemijskim utjecajima. Smjesi su dodane nanočestice aluminijevog oksida u različitim udjelima za svaku membranu, a proces testiranja obavljen je u kiselom mediju pri pH 1 i pH 1,5. U ispitivanju su korištene tri membrane za koje je praćen odziv prema željezovim(III) kationima u otopini željezovog(III) nitrata nonahidrata. Osnovni cilj je bio da se na temelju provedenih ispitivanja donese zaključak o mogućnosti primjene takvih membrana u praksi. Sastav membrana korištenih pri ispitivanju bio je: • Membrana 1 (PNA1) : FePO 4 : Ag 2 S : PTFE = 1 : 1 : 2 s dodatkom nanočestica Al 2 O 3 (0,25%) • Membrana 2 (PNA2) : FePO 4 : Ag 2 S : PTFE = 1 : 1 : 2 s dodatkom nanočestica Al 2 O 3 (0,5%) • Membrana 3 (PNA3) : FePO 4 : Ag 2 S : PTFE = 1 : 1 : 2 s dodatkom nanočestica Al 2 O 3 (1%) Membrane su testirane na odziv prema željezovim(III) kationima u otopini željezovog(III) nitrata nonahidrata. Slijednim mijenjanjem koncentracije sa pufer otopinom dušične kiseline pH vrijednosti 1 i 1,5 praćena je promjena potencijala. Na kraju su dobiveni rezultati prikazani grafički.The potentiometric method was used to test newly developed sensors, ie membrane electrodes based on iron(III) phosphate, silver sulfide with the addition of polytetrafluoroethylene, which is important for the compactness of the mixture and resistance to strong chemical influences. Aluminum oxide nanoparticles were added to the mixture in different proportions for each membrane, and the testing process was performed in an acidic medium at pH 1 and pH 1.5. Three membranes were used in the study, for which the response to iron(III) cations in a solution of iron(III) nitrate nonahydrate was monitored. The main goal was to draw a conclusion based on the conducted tests on the possibility of applying such membranes in practice. The composition of the membranes used in the test was: • Membrane 1 (PNA1): FePO 4 : Ag 2 S: PTFE = 1: 1: 2 with the addition of Al 2 O 3 nanoparticles (0.25%) • Membrane 2 (PNA2): FePO 4 : Ag 2 S: PTFE = 1: 1: 2 with the addition of Al 2 O 3 nanoparticles (0.5%) • Membrane 3 (PNA3): FePO 4 : Ag 2 S: PTFE = 1: 1: 2 with the addition of Al 2 O 3 nanoparticles (1%) Membranes were tested for response to iron(III) cations in a solution of iron(III) nitrate nonahydrate. Subsequent changes in concentration with nitric acid buffer solution pH values of 1 and 1.5 followed the change in potential. In the end, the obtained results are presented graphically