High crystallinity, low oxide content, and low sintering lead to optimally performing mesoporous Si photocatalysts for solar-driven hydrogen production.
Offretite zeolite synthesis in the presence of cetyltrimethylammonium bromide (CTABr) is reported. The offretite crystals were synthesized with a high crystallinity and hexagonal prismatic shape after only 72 h of hydrothermal treatment at 180 °C. The CTABr has dual-functions during the crystallization of offretite, viz. as structure-directing agent and as mesoporogen. The resulting offretite crystals, with a Si/Al ratio of 4.1, possess more acid sites than the conventional offretite due to their high crystallinity and hierarchical structure. The synthesized offretite is also more reactive than its conventional counterpart in the acylation of 2-methylfuran for biofuel production under non-microwave instant heating condition, giving 83.5% conversion with 100% selectivity to the desired product 2-acetyl-5-methylfuran. Hence, this amphiphile synthesis approach offers another cost-effective and alternative route for crystallizing zeolite materials that require expensive organic templates.
sp2 carbon-conjugated COFs (sp2c-COFs) featuring an unparalleled combination of sp2 carbon linkages, extended π-conjugation, high crystallinity, permanent porosity, unique optoelectronic properties, and extraordinary chemical stability, have garnered enormous attention recently.
We prepare poly(pyrrole:biphenyldisulfonic acid:pyrrole (Py:BPDSA:Py)) nanocomposite of molybdenum disulfide (MoS2), P(Py:BPDSA:Py)-MoS2, with high crystallinity. The composite is synthesized by oxidative polymerization of Py:BPDSA:Py as the two-monomer-connected precursors (TMCP) linked by...
Effects of crystallographic quality of grain boundaries on mechanical and electrical properties were investigated experimentally. A novel method using two parameters of image quality (IQ) and confidence index (CI) values based on electron back-scattering diffraction (EBSD) analysis was proposed in order to evaluate crystallographic quality of grain boundaries. IQ value was defined as an index to evaluate crystallinity in region irradiated with electron beam. CI value determined existence of grain boundaries in the region. It was found that brittle intergranular fatigue fracture occurred in the film without annealing and the film annealed at 200 °C because network of grain boundaries with low crystallinity remained in these films. On the other hand, the film annealed at 400 °C caused only ductile transgranular fatigue fracture because grain boundaries with low crystallinity almost disappeared. From results of measurement of electrical properties, electrical resistivity of copper interconnection annealed at 400 °C with high crystallinity (2.09 × 10−8 Ωm) was low and electron migration (EM) resistance was high compared with an copper interconnection without annealing with low crystallinity (3.33 × 10−8 Ωm). It was clarified that the interconnection with high crystallinity had superior electrical properties. Thus, it was clarified that the crystallographic quality of grain boundaries has a strong correlation of mechanical and electrical reliability.
High Crystallinity and Highly Relaxed Al
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Ga
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N Films Using Growth Mode Control Fabricated on a Sputtered AlN Template with High‐Temperature Annealing
