A Monolithically Integrated, Intrinsically Safe, 10% Efficient, Solar-Driven Water-Splitting System Based on Active, Stable Earth-Abundant Electrocatalysts in Conjunction with Tandem III-V Light Absorbers Protected by Amorphous TiO_2 Films

A monolithically integrated device consisting of a tandem-junction GaAs/InGaP photoanode coated by an amorphous TiO_2 stabilization layer, in conjunction with Ni-based, earth-abundant active electrocatalysts for the hydrogen-evolution and oxygen-evolution reactions, was used to effect unassisted, solar-driven water splitting in 1.0 M KOH(aq). When connected to a Ni-Mo-coated counterelectrode in a two-electrode cell configuration, the TiO_2-protected III-V tandem device exhibited a solar-to-hydrogen conversion efficiency, η_(STH), of 10.5% under 1 sun illumination, with stable performance for > 40 h of continuous operation at an efficiency of η_(STH) >10%. The protected tandem device also formed the basis for a monolithically integrated, intrinsically safe solar-hydrogen prototype system (1 cm^2) driven by a NiMo/GaAs/InGaP/TiO_2/Ni structure. The intrinsically safe system exhibited a hydrogen production rate of 0.81 μL s^(-1) and a solar-to-hydrogen conversion efficiency of 8.6% under 1 sun illumination in 1.0 M KOH(aq), with minimal product gas crossover while allowing for beneficial collection of separate streams of H_2(g) and O_2(g)

Infrastructure quality in deregulated industries Is there an underinvestment problem?

Includes bibliographical references. Title from cover. Also available via the InternetAvailable from British Library Document Supply Centre- DSC:3597. 9512(no 3836) / BLDSC - British Library Document Supply CentreSIGLEGBUnited Kingdo

Stereocontrol in Asymmetric S_E′ Reactions of γ‑Substituted α,β-Unsaturated Aldehydes

Asymmetric S_E′ reactions of (<i>E</i>)- and (<i>Z</i>)-γ-substituted-α,β-unsaturated aldehydes have been studied for the stereocontrolled preparation of nonracemic alcohols. Mild exchange reactions of allylic stannanes provide access to chiral 1,3-bis­(tolylsulfonyl)-4,5-diphenyl-1,3-diaza-2-borolidines. These reagents display reactivity with the γ-substituted α,β-unsaturated aldehydes, which is characterized by matched and mismatched elements of stereocontrol. Computational analysis (using density functional theory) provides valuable insights to guide reaction development