Abstract: This invention provides a method for syntheses of new electroluminescent conjugated polymers modified with high electronegative heterocyclic groups (such as 1,3,4-oxadiazole-diyl, 1,3,4-thiadiazole-diyl, and 1,2,4-triazole-diyl). These electroluminescent polymers (homopolymers, statistical copolymers or block coplymers) are obtained by polymerization of bis(halomethyl) arenes modified with heterocyclic groups via the Wessling precursor route, Gilch side chain route, Wittig reaction or Wittig-Hornor reaction. By a proper selection of the monomers and their ratios in the polymerization, the emissive polymers (fully conjugated or limited conjugating length) covering the full visible range even extending to the near-IR range can be prepared. The polymeric light emitting diodes (PLED) with these materials as emissive layer or electron transport layer have high external quantum efficiency and can be used as indicators and displays for cellular phones, pagers, portable computer, wristwatch, toys, etc.

Abstract: A high-sensitivity Pd/InP hydrogen sensor was made by a) forming an n-type or p-type semiconductor film on a semiconductor substrate; b) forming a patterned first metal electrode on said semiconductor film, wherein said first metal electrode forms an Ohmic contact with said semiconductor film; and c) forming a second metal electrode on said semiconductor film, said second metal electrode being isolated from said first metal electrode, wherein said second metal electrode forms a Schottky contact with said semiconductor film, wherein a thickness of said second metal electrode and a material of which said second metal electrode is made enable a Schottky barrier height of said Schottky contact to decrease when hydrogen contacts said second metal electrode. The second metal electrode can be physical vapor deposited or electroless plated.