| Oxygen is an indispensable element to maintain the activities of creatures and the metabolism of organisms.Accurately monitoring oxygen concentration has a great strategic significance in many fields such as environment,medical treatment,biology,chemistry,and the industry as well as food.Therefore,it is necessary to develop oxygen detection technology.The optical oxygen sensors based on dynamic luminescence quenching mechanism have received extensive attention from scientists in recent years.In this paper,2,2-bis(triethoxysilane)ethane(BTESE)and 3,3,3-trifluoropropyltrimethoxysilane(TFP-Tri MOS)are used as the matrix materials,and octaethylporphyrin platinum(Pt OEP)is used as the indicator of the photochemical oxygen sensor.Oxygen sensing film is prepared by a sol-gel method.The effects of indicator amount,precursor ratio,catalyst amount and matrix materials on oxygen sensing performancewere studied.In addition,our work was compared with the relevant studies at the end of the paper.First,the advantages of BTESE and TFP-Tri MOS precursors in the field of oxygen sensors are introduced.The greater the oxygen permeability of the matrix materials,the higher sensitivity of the oxygen sensor,and the stronger the fixation ability of the indicator in the matrix materials,the better stability of the oxygen sensor.Since BTESE can form a loose hybrid silicon network,the prepared gas separation membrane layer has good permeability The NKP fitting curve also proves that the average pore diameter of the silicon membrane prepared by BTESE is larger than that of the TEOS membrane.The introduction of TFP-Tri MOS as the fluorine modified precursor is useful for improving the fixation ability of the matrix material to the indicator since the oxygen indicator is usually a hydrophobic molecule.Therefore,the sensitivity and light stability of the sol-gel oxygen sensor are improved.The BTESE/TFP-Tri MOS oxygen sensor film is successfully prepared by a sol-gel method,and the optimalconditions of the BTESE/TFP-Tri MOS oxygen sensor film are obtained by the control variable method.The amount of the indicator Pt OEP is 6 ?g,and the amount of the two precursors BTESE and TFP-Tri MOS are 2 and 4 mmo L,respectively,and the amount of catalyst HCl is 600 ?L.The oxygen sensing film prepared under this condition showed high detection sensitivity,accuracy,and stability.The maximum quenching ratio of the BTESE / TFP-Tri MOS oxygen sensing film can reach 26.62.It can be seen that the linear correlation coefficient is greater than 0.996 when fitted by the Stern-Volmer equation.The luminescence retention rate of the oxygen sensor can reach 92% when the excitation light source is continuously irradiated for 4000 s.Finally,the performance of the BTESE/TFP-Tri MOS optical oxygen sensor film with the optimum conditions in this paper is compared with the oxygen sensors coupled with Pt OEP as the indicator and prepared with the sol as the precursor,respectively.The results show that the performance of the oxygen sensor prepared in this paper is still insufficient.It has certain limitations for oxygen concentration detection compared with other works with Pt OEP as indicators.However,our developed BTESE/TFP-Tri MOS oxygen-sensing film has higher performance than the oxygen sensor films with other sols as precursors.The oxygen sensing application of BTESE/TFP-Tri MOS can be significantly improved if it is prepared as an oxygen-sensing fiber,and it has great application value in the fields of chemistry,clinical and environmental. |
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