AMMONIA CONCENTRATION SENSOR AND A METHOD FOR FORMING SENSITIVE LAYER

FIELD: analytical instrumentation engineering. ^ SUBSTANCE: invention is intended for use in environmental monitoring and provides ammonia concentration sensor comprising support carrying electrodes, sensitive layer based on urea fragments-containing manganese polyphthalocyanine, and resistive heater. Formation of sensitive layer comprises preparation of urea fragments-containing manganese polyphthalocyanine and subsequent deposition thereof onto support with electrode systems formed on its surface. Preparation of urea fragments-containing manganese polyphthalocyanine involves synthesis of manganese polyphthalocyanine by heating mixture of 0.2 g pyromellitic acid tetranitrile, 4.09 g urea, and 0.058 g anhydrous manganese chloride to 145°C for 1 h and heating at this temperature for further 25 h. Reaction medium is then extracted with boiling ethanol and dried to constant weight. Deposition of urea fragments-containing manganese polyphthalocyanine on support is performed using vacuum thermal spraying technique for 5-8 min at 1000-1200°C. ^ EFFECT: increased sensitivity and selectivity of sensor toward ammonia in mixture with other gases. ^ 3 cl, 3 dwg, 2 tbl, 4 ex