23536-15-4Relevant articles and documents
1,4;5,8-naphthalene-tetracarboxylic diimide derivatives as model compounds for molecular layer epitaxy
Ofir, Yuval,Zelichenok, Alexander,Yitzchaik, Shlomo
, p. 2142 - 2149 (2006)
The physical properties and finite size effects observed in 1,4;5,8-naphthalene-tetracarboxylicdiimide (NTCDI)-based organic multilayers assembled by molecular layer epitaxy (MLE) are investigated by structure-property studies of low molecular weight mode
Organic radical compound and carbon nanotube composites with enhanced electrical conductivity towards high-performance p-type and n-type thermoelectric materials
Chen, Zhanhua,Huang, Hongfeng,Liu, Danqing,Wang, Dagang,Wang, Lei,Wang, Yanzhao
, p. 24675 - 24684 (2020)
Small organic molecules are promising as the next generation of thermoelectric materials due to their unique advantages, such as low cost, high mechanical flexibility, low thermal conductivity, and low toxicity. However, their low electrical conductivities seriously limit the realization of high power factors. Herein, naphthalene diimide derivatives (NDI-1 and NDI-2) carrying a radical substituent of 2,2,6,6-tetramethyl-1-piperidinyloxyl (TEMPO) are designed and complexed with single-walled carbon nanotubes (SWCNTs) as both p-type and n-type thermoelectric composites. The introduction of the radical substituent remarkably improved the electrical conductivity by almost fifty percent compared to that of the NDI derivative without the radical substituent (NDI-0). The obtained radical-containing composites display greatly enhanced TE performance with highest power factors of 277.1 ± 5.4 μW m-1 K-2 for the p-type composite and 79.6 ± 1.7 μW m-1 K-2 for the n-type composite, respectively. Furthermore, the thermoelectric module based on NDI-1/SWCNT composite films consisting of five p-n junctions reaches a large output power of 2.81 μW under a 65 K temperature gradient. The enhanced electrical conductivities and TE performances of radical-containing NDI/SWCNT composite films are attributable to the improved doping level and charge transport process between the radical molecules and SWCNTs. This design strategy of introducing radical moieties into organic thermoelectric materials might be beneficial to the future application for high-performance p-type and n-type thermoelectric materials and devices. This journal is
Polymorphism in: N, N ′-dialkyl-naphthalene diimides
Cavallini, Massimiliano,Cowen, Lewis,Degousée, Thibault,Drain, Ben A.,Fenwick, Oliver,Guagliardi, Antonietta,Liscio, Fabiola,Luong, Sally,Masciocchi, Norberto,Milita, Silvia,Schroeder, Bob C.
, p. 3097 - 3112 (2020)
The long-known class of compounds called naphthalene diimides (NDI), bearing alkyl substituents on the imide nitrogen atoms, have been widely used as active materials in thin film devices with interesting optical, sensing and electrical applications. Less is known about their rich crystal chemical behaviour, which comprises numerous polymorphic transitions, and the appearance of elusive liquid crystalline phases. It is this behaviour which determines the response of the devices based on them. Here we fully characterized, by combining differential scanning calorimetry, powder and thin film diffraction and optical microscopy techniques, two newly synthesized NDI materials bearing n-octyl and n-decyl side-chains, as well as lighter analogues, of known room temperature crystal structures. In search for a rationale of their physico-chemical properties, phase stability and thermally induced solid-state transition reversibility, the differential behaviour of these NDI materials is interpreted here based on the competitive role of intermolecular π-π interactions and the alkyl chain flexibility. The appearance of comparable local minima of the molecular conformational energy hypersurface for shorter alkyls, and, for longer ones, of rotator phases, is here invoked.
