Giant power factor and high air stability in an n-type metal–organic charge-transfer complex

Abstract

The biggest bottleneck delaying the practical applications of organic thermoelectric devices is the lack of high-performance n-type semiconductors with high air-stability. Here, we report an n-type metal-organic coordination complex (Br-C6H4-NH2)2CuBr2....

A New Metal–Organic Complex (Br‐C6H3(I)‐NH2)2CuBr2: Growth and Structural Properties

“…Careful analysis of the reflection conditions revealed a triclinic crystal system with the space group P1, and the cell parameters: a ). [15] In 2022, we reported a new n-type metal-organic complex (Br-C 6 H 4 -NH 2 ) 2 CuBr 2 with extremely high thermoelectric properties [8] (see Table 4). This material shows a high power factor (PF) of >1589 μW m -1 K -2 , maximum figure of merit (ZT) of 0.27, and excellent air stability of >405 d. The (Br-C 6 H 4 -NH 2 ) 2 CuBr 2 complex is just the tip of the iceberg in metal-ligand coordination system [R-C 6 H 4 -NH 2 ] 2 MX 2 (R-C 6 H 4 -NH 2 is aromatic amines, M is transition metals, and X is halogens).…”

“…The difference between molecular structures of 4BA-CuBr 2 and (Br-C 6 H 4 -NH 2 ) 2 CuBr 2 is shown in [8] Yellow, brownish red, purple, blue, grey, and light pink spheres represent Cu, Br, I, N, C, and H atoms, respectively. Table 5.…”

“…As shown in Figure 6a, the intermolecular interaction of compound 4BA-CuBr 2 along the c-axis is mediated by hydrogen bonding modules, whose corresponding equatorial and axial distances As shown in Figure 7, the effected connection is featured with a (C-H•••C) distance of 3.640(5) Å, which can strengthen the cohesion between benzene in P 1 and the para-carbon on benzene in the parallel surface, owing to parallel movement of the benzene ring. The vector between the benzene ring normal and the carbon element at the corresponding position of the adjacent benzene ring forms an angle of 𝛼 = 41.939°, leading to a distance of d = 4.783 (8) Å between the centroids. [17] The accumulation of aromatic rings is accompanied by the appearance of cohesion between crystals [18] To explicitly describe the relative orientation of the two benzene rings, accurately, six geometric parameters are required.…”

“…[ 7 ] In 2022, a new type of n‐type metal–organic charge transfer complex (Br‐C 6 H 4 ‐NH 2 ) 2 CuBr 2 with outstanding thermoelectric performance was reported. [ 8 ] This type of materials exhibits low toxicity, low material cost, flexibility, and easy processing. Based on above‐mentioned advantages, more new metal–organic complexes should be developed so that scientists in thermoelectric fields can explore their potential applications.…”

“…Based on our previous research, [ 8 ] here, we designed a new metal–organic complex (Br‐C 6 H 3 (I)‐NH 2 ) 2 CuBr 2 , hereinafter called as bis (4‐bromo‐2‐iodoaniline) di‐bromidocopper and denoted 4BA‐CuBr 2 . Single crystals of a metal–organic complex 4BA‐CuBr 2 were grown by a vapor diffusion method.…”