Detection of Ammonium Ion by An Electrochemical Sensor Based on Cu-BTC

Abstract

Abstract There is a growing interest in utilizing metal-organic frameworks (MOFs) for the development of electrochemical sensors with superior performance. In this work, a study on the detection of ammonium ion (NH4 +) on metal-organic frameworks (MOFs) Cu-BTC surface has been conducted by using both experimental and computational methods. By using DFT calculation, the adsorption energy of ammonium ion (NH4 +) on the MOF surfaces was determined. The calculation result showed that NH4 + molecules can be adsorbed on the surface of Cu-BTC with an adsorption energy value of -1.51 eV. Additionally, we performed the synthesis of Cu-BTC and, using CV (Cyclic Voltammetry), we obtained a working area of around -0.113 V. Furthermore, chronoamperometry tests revealed that the addition of ammonium at concentrations of 0.05, 0.1, and 0.15 mM resulted in changes in the current. The sensor also showed good stability and an increase in peak current at each tested concentration. This confirms that the MOFs tested can be utilized as ammonium ion sensors.