Amino Anthraquinone: Synthesis, Characterization, and Its Application as an Active Material in Environmental Sensors

Salman Ali; Muhammad Tahir; Nasir Mehboob; Fazal Wahab; Steven J Langford; Suhana Mohd Said; Mahidur R Sarker; Sabariah Julai; Sawal Hamid Md Ali

doi:10.3390/ma13040960

Amino Anthraquinone: Synthesis, Characterization, and Its Application as an Active Material in Environmental Sensors

Materials (Basel). 2020 Feb 21;13(4):960. doi: 10.3390/ma13040960.

Authors

Salman Ali¹, Muhammad Tahir^{2

3}, Nasir Mehboob⁴, Fazal Wahab⁵, Steven J Langford⁶, Suhana Mohd Said³, Mahidur R Sarker⁷, Sabariah Julai⁷, Sawal Hamid Md Ali⁸

Affiliations

¹ Faculty of Science, Engineering and Technology, Swinburne University of Technology, Hawthorn Victoria 3122, Australia.
² Department of Physics, Faculty of Physical and Numerical Sciences, Abdul Wali Khan University Mardan, Khyber Pakhtunkhwa 23200, Pakistan.
³ Department of Electrical Engineering, Faculty of Engineering, University of Malaya, Kuala Lumpur 50603, Malaysia.
⁴ Department of Physics, Riphah International University, Islamabad 45210, Pakistan.
⁵ Department of Physics, Karakoram International University, Gilgit 15100, Pakistan.
⁶ Department of Chemistry and Biotechnology, Swinburne University of Technology, Hawthorn Victoria 3122, Australia.
⁷ Department of Mechanical Engineering, Faculty of Engineering, University of Malaya, Kuala Lumpur 50603, Malaysia.
⁸ Department of Electric, Electronics and System Engineering, Faculty of Engineering and Built Environment, Universiti Kebangsaan Malaysia, Bangi 43600, Malaysia.

Abstract

This work reports synthesis, thin film characterizations, and study of an organic semiconductor 2-aminoanthraquinone (AAq) for humidity and temperature sensing applications. The morphological and phase studies of AAq thin films are carried out by scanning electron microscope (SEM), atomic force microscope (AFM), and X-ray diffraction (XRD) analysis. To study the sensing properties of AAq, a surface type Au/AAq/Au sensor is fabricated by thermally depositing a 60 nm layer of AAq at a pressure of ~10^-5 mbar on a pre-patterned gold (Au) electrodes with inter-electrode gap of 45 µm. To measure sensing capability of the Au/AAq/Au device, the variations in its capacitance and resistance are studied as a function of humidity and temperature. The Au/AAq/Au device measures and exhibits a linear change in capacitance and resistance when relative humidity (%RH) and temperature are varied. The AAq is a hydrophobic material which makes it one of the best candidates to be used as an active material in humidity sensors; on the other hand, its high melting point (575 K) is another appealing property that enables it for its potential applications in temperature sensors.

Keywords: 2-aminoanthraquinone (AAq); AFM; humidity sensor; organic semiconductor sensor; temperature sensor.