Enhanced photoelectrochemical and sensing performance of TiO2/NiOOH/Ag to glucose

Diabetes is mainly caused by abnormal increase of blood glucose level, the corresponding glucose sensor can be used to monitor the concentration of glucose. TiO2/NiOOH composite sensor was prepared by a facile method of electrodeposition of NiOOH on TiO2 nanotube arrays (TNT), and triangle Ag sheets modified by photodeposition. The structures and photoelectric properties were characterized by electrochemical workstation. It was found that NiOOH could effectively improve the photoelectrochemical properties of TNT. When Ag was further photodeposited on TNT/NiOOH, the photocurrent density improved at 0.21 mA/cm2. The enhanced photoelectrochemical properties can be attributed to the extended visible light absorption and effective separation of photo-generated carriers by the synergistic effect of Ag and NiOOH. The modified TNT/NiOOH exhibited much stronger photoelectrochemical reduction property toward glucose in comparison to pure TNT. The sensitivity of TNT/NiOOH/Ag to glucose can reach 2490 μA·cm−2·mM−1 and its detection limit low to 0.44 μM.