Rational design of the microstructure and intrinsic active sites of nitrogen-doped carbon (NC) materials to achieve highly efficient oxygen reduction reaction (ORR) electrocatalysts is extremely important for many renewable energy devices. Herein, we develop a metal–organic framework (MOF) derived metal-free NC material via a simple and low-cost NH3 activation strategy. With NH3 activation, the ORR catalytic performance of the MOF-derived material shows a great promotion. The material outperforms commercial Pt/C catalyst toward ORR catalysis in alkaline media with ∼28 mV higher half-wave potential. This amazing ORR performance might be attributed to its large specific surface area, hierarchical porosity, and full exposure of valid N species (mainly graphitic-N) to the ORR, which result from the facile NH3 activation.

Highly ordered organic semiconductor micropatterns of the liquid-crystalline small molecule 2,7-didecylbenzothienobenzothiophene (C10 -BTBT) are fabricated using a simple method based on template-assisted self-assembly (TASA). The liquid crystallinity of C10 -BTBT allows solvent-free fabrication of high-performance printed organic field-effect transistors (OFETs).

A series of poly(amic acid)s have been synthesized from cyclobutane‐1,2,3,4‐tetracarboxylic dianhydride (CBDA), a functional diamine, 1‐(3,5‐diaminophenyl)‐3‐(1‐octadecyl)‐succinicimide and 4,4‐diaminodiphenylmethane (DDM) to give liquid crystal alignment layers with high pretilt angle after a rubbing process for vertically aligned liquid crystal display devices. Inherent viscosities of the poly(amic acid)s measured were in the range 0.2–1.56 dl/g, which decreased with an increase of content of 1‐(3,5‐diaminophenyl)‐3‐(1‐octadecyl)‐succinicimide. The cured polyimide films had good transparency, which was above 95% at 400 nm. Surface energies of all the polyimide films prepared from 1‐(3,5‐diaminophenyl)‐3‐(1‐octadecyl)‐succinicimide were below 40.7 dyn/cm before the rubbing process, which resulted in very high pretilt angles above 89°. By a rubbing process, the surface energy of the polyimide prepared from diamine mixture with 10 mol% of 1‐(3,5‐diaminophenyl)‐3‐(1‐octadecyl)‐succinicimide and 90% of DDM increased from 40.7 to 42.7 dyn/cm. Copyright © 2007 John Wiley & Sons, Ltd.

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