Conductive Metallophthalocyanine Framework Films with High Carrier Mobility as Efficient Chemiresistors

Abstract

The poor electrical conductivity of two‐dimensional (2D) crystalline frameworks greatly limits their utilization in optoelectronics and sensor technology. Herein, we describe a conductive metallophthalocyanine‐based NiPc‐CoTAA framework with cobalt(II) tetraaza[14]annulene linkages. The high conjugation across the whole network combined with densely stacked metallophthalocyanine units endows this material with high electrical conductivity, which can be greatly enhanced by doping with iodine. The NiPc‐CoTAA framework was also fabricated as thin films with different thicknesses from 100 to 1000 nm by the steam‐assisted conversion method. These films enabled the detection of low‐concentration gases and exhibited remarkable sensitivity and stability. This study indicates the enormous potential of metallophthalocyanine‐based conductive frameworks in advanced stand‐off chemical sensors and provides a general strategy through tailor‐make molecular design to develop sensitive and stable chemical sensors for the detection of low‐concentration gases.

Three-dimensional porphyrinic covalent organic frameworks for highly efficient electroreduction of carbon dioxide

“…32–44 Moreover, the associated unique features such as strong CO 2 adsorption capacity and single active sites make COFs to be a good choice for CO 2 RR. 45–57 Since Yaghi and co-workers first reported that the cobalt porphyrin-based COF-366-Co can catalyze the CO 2 RR to produce CO, 58 several other metal porphyrin- and phthalocyanine-based COFs have been reported as electrodes to promote the CO 2 RR in aqueous medium. 59,60 However, due to the face to face lamellar stacking, the active sites in the layers of 2D COFs cannot be fully exposed to electrolytes and CO 2 , which usually leads to low activity and current density.…”

Porphyrin‐Based COF 2D Materials: Variable Modification of Sensing Performances by Post‐Metallization

“…Notably, no apparent change of current was observed toward 10 commonly cross‐sensitive gases involving SO 2 , [20] a representative interference gas for NO 2 , implying that Co‐TPCOF possessed excellent selectivity. As far as we know, such unusual specific selectivity has rarely been reported for NO 2 sensing materials [3a, 4, 10b] …”

Morphology induced enhanced photoconductivity of a phthalocyanine-based benzimidazole linked two-dimensional conjugated covalent organic polymer

“…2,[8][9][10][11][12] In this regard, 2D polymers with columnar assemblies, so called 2D covalent organic frameworks (COFs), have emerged as ideal platforms for constructing photoconductive devices since they fulfil both descript criteria, but have the shortcoming of requiring elaborate structural design and considerable synthetic effort to obtain specific alignment. [13][14][15][16][17][18][19] Moreover, studies also report that such design also increases the photo responsive speed of polymers compared to disordered 2D p-conjugated polymers. 8 However, one should note that, while 2D columnar assembly increases the conductivity of the generated electricity due to additional conductive pathways, at the same time it causes a reduction of electric generation due to limited absorption of photons by adsorbents.…”

“…2,8–12 In this regard, 2D polymers with columnar assemblies, so called 2D covalent organic frameworks (COFs), have emerged as ideal platforms for constructing photoconductive devices since they fulfil both descript criteria, but have the shortcoming of requiring elaborate structural design and considerable synthetic effort to obtain specific alignment. 13–19 Moreover, studies also report that such design also increases the photo responsive speed of polymers compared to disordered 2D π-conjugated polymers. 8…”

“…The photoconductive polymers can be built upon the incorporation of highly electron-rich intrinsic semiconductive and photoconductive building blocks, such as pyrene, porphyrin and phthalocyanine (Pc), into the polymer backbone. 2,15,[17][18][19][21][22][23][24][25] Among these building blocks, Pcs are a class of planar aromatic organic compounds that have attracted considerable attention due to their unique properties, such as semi-conductivity, photoconductivity, photochemical reactivity, and chemical stability. 16,[26][27][28][29][30][31][32][33][34][35][36][37] To date, significant effort has been put into designing and preparing Pc-based devices with high conductivity.…”