Highly selective room-temperature NO₂ sensors based on a fluoroalkoxy-substituted phthalocyanine

Abstract

A new n-type phthalocyanine-based sensor is developed for ultrasensitive and highly selective detection of trace amounts of NO2 against NH3 and H2S.

A high-sensitive room temperature gas sensor based on cobalt phthalocyanines and reduced graphene oxide nanohybrids for the ppb-levels of ammonia detection

“…It is well-known that metal phthalocyanines (MPcs) are also good gas sensitive materials due to their unique conjugated 18p-electron structure. 21 There are 16 hydrogen atoms around the phthalocyanine ring, which can be substituted by other groups, such as alkoxy group, carboxyl group, amino group and sulfonic acid group [22][23][24] which provides an opportunity to improve and optimize the NH 3 -sensing performance of rGO by using substituted MPcs as dopants. In addition, there is a hole in the ring that can accommodate a variety of different metal elements to form different kinds of metal phthalocyanines.…”

Hierarchical Self‐Assembly of Tetrakis(1‐pyrenyl)porphyrins into Microscopic Petals and Flowers with Ultrasensitive Room‐Temperature NO2 Sensing in a Broad Humidity Range

“…So one CoT[(Pyr) 4 ]P molecule can further form coordination structure with two NO 2 molecules. However, the porphyrin ring of 1 contains two interior NH protons that can form hydrogen bonds with two NO 2 molecules . By comparing with those of 1 , the open surface metal coordination sites of 2 could strongly bind to NO 2 molecules, which makes them more difficult to desorption.…”

“…However, the porphyrin ring of 1 contains two interior NH protons that can form hydrogen bonds with two NO 2 molecules. [13] By comparing with those of 1, the open surface metal coordination sites of 2 could strongly bind to NO 2 molecules, which makes them more difficult to desorption. Therefore, for the aggregates of 2, the response gradually approached the saturated status to the relatively high concentration of NO 2 when the much more NO 2 molecules completely bind to CoT[(Pyr) 4 ]P metal centers of the semiconducting layer and the redundant gases have little contribution to the conductivity at RH = 0% (without H 2 O molecules).…”

“…[5][6][7][8] Among the large family of organic semiconductor materials, tetrapyrrole derivatives including porphyrins and phthalocyanines with large π-conjugated electronic molecular structures have attracted considerable research interest owing to their high thermal and chemical stability and rich substitution chemistry as well as strong π-π intermolecular interaction in solid state, resulting in intriguing electronic and optical properties [9] and potential applications as gas sensor. [4,[10][11][12][13][14] For example, a vacuum deposited film of cobalt phthalocyanine is revealed to exhibit a quite stable response and discrimination between 12, 25 and 50 ppm of NH 3 over the 10-70% RH range. [4] However, articles which focus specifically on cross sensitivity between NO 2 and humidity are quite rare.…”

“…Compared with the most inorganic compounds, organic semiconductor materials as the chemically sensitive component of chemical/conductometric transduction systems have been emerged and become the promising candidates for gas sensors due to their advantages in terms of tunable molecular structures, great processability, low cost production, selective detection and especially low operating temperature . Among the large family of organic semiconductor materials, tetrapyrrole derivatives including porphyrins and phthalocyanines with large π‐conjugated electronic molecular structures have attracted considerable research interest owing to their high thermal and chemical stability and rich substitution chemistry as well as strong π–π intermolecular interaction in solid state, resulting in intriguing electronic and optical properties and potential applications as gas sensor . For example, a vacuum deposited film of cobalt phthalocyanine is revealed to exhibit a quite stable response and discrimination between 12, 25 and 50 ppm of NH 3 over the 10–70% RH range .…”