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In this study, we have designed and synthesized a novel ZnO@CuO core-shell heterojunction photoanode modified with cocatalyst ZnFe-layered double hydroxides (ZnFe-LDH). As expected, the deposition of CuO enhances light harvesting and shortens the diffusion distance for charge transfer. The ZnO@CuO heterojunction also enhances charge separation and suppresses recombination. Furthermore, modification with cocatalyst ZnFe-LDH facilitates photogenerated hole transport and accelerates the surface oxidation reaction kinetics. On account of the synergistic effect of the core-shell heterojunction in ZnO@CuO with cocatalyst ZnFe-LDH, this photoanode exhibits an optimal photocurrent density of 2.08 mA cm-2 at 1.23 V vs. RHE, which is about 5.3 times that of the pristine ZnO photoanode. Therefore, the construction of ZnO@CuO core-shell nanorod arrays coupled with cocatalyst ZnFe-LDH provides an effective and novel route for designing low-cost and high-efficiency photoelectrodes.Microcapsules are commonly used in applications ranging from therapeutics to personal care products due to their ability to deliver encapsulated species through their porous shells. Here, we demonstrate a simple and scalable approach to fabricate microcapsules with porous shells by interfacial complexation of cellulose nanofibrils and oleylamine, and investigate the rheological properties of suspensions of the resulting microcapsules. The suspensions of neat capsules are viscous liquids whose viscosity increases with volume fraction according to a modified Kreiger-Dougherty relation with a maximum packing fraction of 0.74 and an intrinsic viscosity of 4.1. When polyacrylic acid (PAA) is added to the internal phase of the microcapsules, however, the suspensions become elastic and display yield stresses with power-law dependencies on capsule volume fraction and PAA concentration. The elasticity appears to originate from associative microcapsule interactions induced by PAA that is contained within and incorporated into the microcapsule shell. selleck chemicals These results demonstrate that it is possible to tune the rheological properties of microcapsule suspensions by changing only the composition of the internal phase, thereby providing a novel method to tailor complex fluid rheology.This work reports the development of renewable cellulose nanocrystal (CNC) and ionic liquid (IL) hybrid materials for bending actuator applications. For this purpose, cellulose nanocrystals with different surface charges (neutral, positive and negative) were prepared and increasing amounts of the IL 2-hydroxy-ethyl-trimethylammonium dihydrogen phosphate ([Ch][DHP]) (10 and 25 wt%) were incorporated into the CNC hosting matrix. The morphology of the samples was evaluated, proving that both surface charge and IL incorporation do not affect the characteristic layered structure of the CNC. Atomic force microscopy results reveal a sea-island morphology in the hybrid films, where CNC bundles are surrounded by [Ch][DHP]-rich regions. An increase in the electrical conductivity is observed upon IL incorporation into the CNC matrix, regardless of the CNC surface charge. The highest electrical conductivity values are observed for IL/CNC (+) 25 wt% with an electrical conductivity of 3.18 × 10-5± 2.75 × 10-7 S cm-1 and IL/CNC (-) 10 wt% (1.26 × 10-5± 5.92 × 10-6 S cm-1). The highest bending displacement of 2.1 mm for an applied voltage of 4.0 Vpp at a frequency of 100 mHz was obtained for the IL/CNC (+) 25 wt% composite, demonstrating the suitability of cellulose to develop soft actuators.We propose a novel strategy to introduce platinum into the metal nodes of ZIF-8 by preloading Pt as a dopant in ZnO (Pt-ZnO) and then convert it to Pt doped ZIF-8 (Pt-ZIF-8) through a chemical vapor deposition (CVD) approach. The solvent-free conversion of Pt-ZnO to Pt-ZIF-8 allows the Pt dopant in ZnO to coordinate with organic linkers directly without the formation of Pt nanoparticles, which is a general issue of many methods. This general synthesis strategy may facilitate the discovery of MMOFs that have not been reported previously.Reducing the overpotential and increasing the reaction rate, which are respectively determined by the thermodynamics and kinetics of electrocatalysis, are the keys to obtaining high-performance bifunctional electrocatalysts for the OER/ORR. Herein, six late-transition metals (Ru, Rh, Pd, Os, Ir, and Pt) anchored on γ-GY and graphitic N doped γ-GY substrates are screened as electrocatalysts for the OER and ORR via density functional theory, and the effects of electronic regulation due to the presence of graphitic N on the thermodynamics and kinetics of electrocatalysis are investigated in detail. Among the six γ-GY@TM candidates, only γ-GY@Rh exhibits excellent OER activity, with an overpotential of 0.42 V. Furthermore, graphitic N doped graN-γ-GY@Rh shows outstanding bifunctional electrocatalytic activity, with overpotentials of 0.27 V for the OER and 0.33 V for the ORR, which are remarkably superior to the values of 0.43 V for RuO2 and 0.45 V for noble-metal Pt electrocatalysts. The present results present some of the lowest overpotentials for OER/ORR electrocatalysts given by theoretical studies to date. From a kinetics point of view, N-doping also remarkably reduces the activation energy barriers of the catalytic rate-limiting steps of the OER and ORR, accelerating the reaction processes and significantly improving the conductivity. Our work provides a theoretical strategy for designing high-efficiency bifunctional OER/ORR electrocatalysts based on γ-GY materials.Herein, we describe unprecedented access to all-carbon or heterocyclic seven-membered ring frameworks from 1,8-ene-ynes promoted by inexpensive low-valent titanium(ii) species, readily available from Ti(OiPr)4 and Grignard reagent. A broad range of cycloheptane, azepane or oxepane derivatives has been obtained (19 examples) with moderate to good yields and an excellent selectivity (up to 95/5 d.r.).A simpler and less expensive fabrication process is one of the essential demands for the commercialization of perovskite solar cells (PeSCs). Especially, inverted PeSCs (I-PeSCs) require a cathode buffer layer (CBL) for fabricating highly efficient and stable PeSCs. However, this increases the number of fabrication step. Here, we demonstrate highly stable and efficient cathode-buffer-layer-free I-PeSCs via additive engineering on an ETL, which is based on phenyl-C61-butyric acid methyl ester (PC61BM) with a small amount of poly(methyl methacrylate) (PMMA). This modified ETL shows not only a simplified fabrication process but also effective extraction of charge from the perovskite to a high work function copper electrode (Cu) by formation of an interfacial dipole at the interfaces between the ETL and the Cu. Additionally, it exhibits good passivation of the trap density existing along the grain boundaries and surface of the perovskite layer, reducing the non-radiative recombination and consistent with the increases in open-circuit voltage (Voc).