Bias and humidity effects on the ammonia sensing of perylene derivative/lutetium bisphthalocyanine MSDI heterojunctions

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

“…However, the high operating temperature (normally 200–500 °C) for metal oxide‐based gas sensors not only increase the difficulties in the preparation process but severely limits their practical applications in many areas, such as low temperatures environments . Moreover, published works hardly reported the effect of humidity variation on the gas sensing response despite this point being of the utmost importance in the practical application . Therefore, developing ultrasensitive room‐temperature gas sensors that can be operated at broad humidity ranges are highly desired.…”

“…[1][2][3] Moreover, published works hardly reported the effect of humidity variation on the gas sensing response despite this point being of the utmost importance in the practical application. [4] Therefore, developing ultrasensitive room-temperature gas sensors that can be operated at broad humidity ranges are highly desired.…”

“…[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.…”

“…[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.…”

“…With this background in mind, we focus our attention on exploring high-performance sensing semiconducting materials through suitable molecular design as well as efficient self-assembly. Here, two porphyrin molecules, 5,10,15,20-tetrakis(1-pyrenyl)porphyrin H 2 T[(Pyr) 4 ]P (1) and its cobalt congener CoT[(Pyr) 4 ]P (2) (Scheme 1) were employed in our study, for the following reasons: (1) the conjugated tetrapyrrole rings can facilitate efficient π-electron delocalization and favor dense intermolecular π-π stacking; (2) the four aromatic pyrene substituents at the porphyrin periphery not only ensure their good solubility in conventional organic solvents, but importantly, offer other interaction motifs, such as pyrene-participated π-π stacking and hydrophobic interactions that are expected to promote electron transport and sensing stability in a wide RH range, and (3) in-plane feature of a cobalt (II) porphyrin complex, may offer promising possibilities for increasing the π-conjugation of the tetrapyrrole backbone. A simple solution process allows us to controllably prepare large quantities of well-defined supramolecular self-assemblies.…”