The hydrogen getter consisting of 1,4-bis­[phenylethynyl]­benzene (DEB) and a carbon-supported palladium catalyst (Pd/C) is limited by its powder forms in practical application. Development of the molded DEB-Pd/C is thus highly demanded. To solve the contradiction between molding and hydrogen-getter rate, herein, we prepared a porous polymer matrix composite for DEB-Pd/C by a facile one-phase removal method of their cocontinuous polymer matrices. Such a porous composite exhibits excellent hydrogen-getter activities. More interestingly, under low hydrogen partial pressure, the porous composite had a faster getter rate than that of powder getters. The significantly enhanced activity is attributed to the confinement effects of the continuous pore structure of the polymer frameworks, which further indicates its promise as a highly active and flexible supporting framework for hydrogen absorption or other gas–solid reactions.

We have developed a new selective-growth process of InP on exactly (100)-oriented Si substrate in a conventional low-pressure metal-organic vapor-phase-epitaxy system. In this process, the InP epitaxial layer was deposited on a photolithographically patterned InP-buffer film without an additional dielectric mask during the growth. Under our experimental conditions, the InP growth has a very high selectivity and the InP epitaxial layer is antiphase-domain free. Experimental results show that the undesirable sidewall-growth interaction in conventional dielectric mask selective-growth processes is effectively suppressed. Spatially resolved photoluminescence displayed very high optical quality of patterned InP layers compared to those grown on blanket substrates.

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Carrier concentration and mobility of unintentionally doped InP layers, grown directly on Si using metal-organic vapor-phase epitaxy, have been studied. The formation of antiphase domains (APDs) was found to depend on annealing of the Si substrate in an AsH3 flow prior to epitaxial growth. Dislocation densities determined by the wet chemical delineation technique were (8±1)×107 cm−3, seemingly uncorrelated to APDs in the layers. In addition to a shallow donor and a compensating acceptor, a deep donor was observed affecting the temperature dependence of the free-electron concentration between 77 and 300 K. The electron mobility in this temperature range could be described in terms of the scattering mechanisms which are dominant in homoepitaxial InP, namely, scattering due to polar optical phonons, to ionized impurities, and to space charges. Electron scattering due to either of these mechanisms was strongly influenced by the occurrence of antiphase boundaries (APBs). The space-charge density as well as the degree of compensation of the epitaxial layers increases with the density of APBs. Degraded 300 K mobilities were obtained indicating the effect of local stress at the APB.