Fluorinated Metal Phthalocyanine Nanowires and their Applications in Gas Sensing
Discipline: Nanoscience
Subcategory: Nanoscience
Session: 2
Room: Exhibit Hall A
Juan Antonio Cintrón Cruz - University of Puerto Rico, Rio Piedras Campus
Co-Author(s): Jean C. González, University of Puerto Rico, Río Piedras Campus; Molecular Science Research Center, PR; Dalice M. Piñero, University of Puerto Rico, Río Piedras Campus; Molecular Science Research Center, PR; Luis Fonseca, University of Puerto Rico, Río Piedras Campus, PR; Soraya Flores, University of Puerto Rico, Río Piedras Campus, PR; Dara L. Rodriguez, University of Puerto Rico, Río Piedras Campus, PR; Oliver Pichardo, University of Puerto Rico, Río Piedras Campus, PR; Fernando Camino, Brookhaven National Laboratory, USA
Metal phthalocyanines (MPcs) are one of the most versatile complexes used as organic semiconductors for multiple applications, from dyes and pigments to materials for electronics, optics and gas sensing devices. Their 18 pi-conjugated macrocycle give them high stability and allows for fine modifications in the peripheral positions that change the properties of the parent complex. The choice of the metal ion at the center of the molecule can also influence the selectivity of the MPc based sensor towards a particular gas. For example, NiPc and CuPc thin films have been used for the detection of NO2 at concentrations as low as 10 ppm. Metal phthalocyanines are highly stable which allows for their incorporation in different architectures including thin films, nanowires and 2D-MOFs. However, the most common MPc sensors found in the literature are based on thin films. In this project we propose the use nanostructures as a way to increase the sensitivity of the gas sensors. The other purpose of this project is to study how fluoro substitutions in the macrocycle of the phthalocyanine macrocycle influence the gas sensing properties of the device. Here we report the first results obtained from the construction of the sensing devices. We first synthesized fluorinated and unsubstituted metal phthalocyanines from Zn, Cu, Ni, Co, Fe and Mn using various methods including solvothermal conditions and solid-state synthesis. The metal phthalocyanines were characterized by UV-vis spectroscopy, FT-IR spectroscopy and X-ray diffraction. We then used the complexes to grow nanowires by using chemical vapor deposition (CVD) including the first nanowires based on fluorinated Mn, Fe, Co, Ni, and Zn phthalocyanines. The MPc and MPcF16 nanowires were then deposited over four-point electrodes and characterized by using the scanning electron microscope (SEM). These devices are currently being used for making the gas sensing measurements. Future work involves finishing the complete gas sensing measurements for all the devices to establish a full comparison between the different complexes and structures. References: Korotcenkov, G. Handbook of Gas Sensor Materials: Properties, Advantages and Shortcomings for Applications, 1st ed.; Springer: New York, 2014; Vol. 2. Qiu, C.-J.; Dou, Y.-W.; Qu, W.; Sun, Y.-M. Nitrogen Dioxide Sensing Properties and Mechanism of Nickel Phthalocyanine Film. Second International Conference on Smart Materials and Nanotechnology in Engineering 2009. Tong, W. Y.; Djurišić, A. B.; Xie, M. H.; Ng, A. C. M.; Cheung, K. Y.; Chan, W. K.; Leung, Y. H.; Lin, H. W.; Gwo, S. Metal Phthalocyanine Nanoribbons and Nanowires. The Journal of Physical Chemistry B 2006, 110(35), 17406–17413.
Funder Acknowledgement(s): I thank Dr. Pinero, my colleagues in her coordination chemistry research group, and the CIRE2N team for all their support in my research career. This research work was possible thanks to the funding and facilities of the UPR, the NSF-CREST CIRE2N, Grant Number HRD-1736093, PR-LSAMP, Grant Number HRD- 1400868, the MSRC and the X-ray diffractometer acquired through the support of the NSF, Award Number CHE-1626103.
Faculty Advisor: Dr. Dalice M. Piñero, dalicempinero@gmail.com
Role: My role in this project was to synthesize, and characterize the complete set of metal phthalocyanines used for constructing the device. I was also involved in the synthesis of the nanowires but I was not the main contributor in this part of the project.