THE EFFECT OF KOBALT (Co) ADDITION IN MOF (METAL ORGANIC FRAMEWORK) HKUST-1 AS METAL OXIDE CuCo2O4 TEMPLATE FOR NON ENZIMATIK GLUCOSE SENSOR

• Main Author: Delia Aisyah, Astrid
• Format: Theses
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/43530
• Institution: Institut Teknologi Bandung

Diabetes mellitus is one of the biggest health problems in the world because almost 430 million of the world's population is positive for diabetes at this time. Indonesia gets sixth rank in the number of diabetes suffers in the world. Diabetes mellitus is caused by excessive glucose levels in the blood and can be fatal so that it leads to death. Therefore, it is important to detect glucose levels accurately and quickly in the blood, so that the diabetics can control their glucose levels. There are two types of sensors to detect glucose levels in the blood, using enzymatic glucose sensors and non-enzymatic glucose sensors. In this research, the material will be made for non enzymatic glucose sensors because it has various advantages including high stability, high sensitivity and low cost. The material used is CuCo2O4 metal oxide material that obtained from the combustion process of metal organic framework (MOF) type HKUST-1 (Cu-BTC) with the addition of cobalt metal (Co). MOF with HKUST-1 (Cu-BTC) type is used in this study because Cu has high sensitivity and selectivity and a low detection limit for glucose. Addition of Co (cobalt) metal to MOF CuBTC (HKUST-1) was carried out because Co metal has a high surface area and electrocatalytic ability which can increase oxidation and reduction levels in electrochemical testing. The synthesis used solvothermal method at 1300 C for 8 hours. Then the 5000 C combustion process was carried out for 1 hour with nitrogen furnace to obtain CuCo2O4 metal oxide material. The variations of Co doping are 10%, 30%, 50%, 70% and 90%. Samples were characterized by TG / DTA, X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM), Fourier Transform Infrared (FTIR), Brunauer Emmett Teller (BET) Surface Area Analyzer and non-enzymatic glucose sensor performance testing by electrochemical method. Based on the MOF CuCoBTC diffraction pattern, there are peaks at 2? = 9.40; 11.50; 13.40 which is in accordance with the reference. The metal oxide diffraction pattern CuCo2O4 shows that there is a peak at 2? = 35.50; 38.70 and 49.20 which are in accordance with JCPD-ICDD: 78e2177. SEM results of CuCoBTC and CuCo2O4 show that the particles morpholgy are octahedral. The addition of Co in Cu-BTC MOF changes the regularity of octahedral structures. MOF CuCoBTC with 50% cobalt addition has a surface area of 692 m2 / g. FTIR results show that BTC ligands formed at wave numbers 1641.42 - 939.33 nm will disappear when the combustion process is carried out to form metal oxide material. The sensor performance test was carried out by the electrochemical method with the cyclic-voltammetry (CV) technique in the range of -0.2 - 0.6 V and the scan rate of 50 mV / s. Based on the results of the CV test, it was found that MOF CuCoBTC-50% has the highest oxidation peak (19.26 µA and 0.32 V) when compared to other cobalt variations. But when compared with CuCo2O4 - 50% metal oxide, metal oxide has a higher oxidation rate (115.5 µA and 0.36 V) when compared to MOF CuCoBTC-50%. The sensitivity of the sensor can be determined using the amperometri method and the sensitivity is 8620 ?A Mm-1 cm-2 with a limit of detection 1.2 ?M. The Selectvity sensors can be identified by testing 0.2 mM glucose, uric acid, NaCl and dopamine. The test result shows that the CuCo2O4 sensor material is more selective for glucose. For stability, the oxidation peaks were checked with CV for 3 months. And it was found that the stability of the sensor performance decrease until 93% in the 3rd month experienced.