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Semiconductor photocatalyst approaches for solar CO2 reduction are attractive due to their simplicity but have lagged in efficiency compared to less-integrated photoelectrochemical (PEC) approaches and to electrolysis reactors. We identify poor mass transport and catalyst deactivation as key constraints. To address them, we have developed a continuous-flow photocatalytic reactor system allowing us to control the triple-phase interface on the photocatalyst surface using the liquid and reactant gas flow rates. With the goal of selectively producing CO, the reactor is optimized by controlling the pressure and flow rates of the reactant gas and electrolyte in contact with both sides with the intermediately placed catalyst. In comparison to batch reactors with an immobile photocatalyst bed and gas phase CO2 or CO2 purged water, 10-24 times higher production rates are achieved for photocatalysts such as TiO2, ZnO, C3N4, and CdS by simply changing to the designed flow-type photoreactor without any catalyst modification. In addition, CO selectivity (93.2%) and long-term stability (>780 min) using the designed reactor are significantly enhanced compared to using the batch reactors (71.7%,

In a recent issue of Nature, Zhou et al. report an artificial photosynthesis scheme that splits water into hydrogen and oxygen with an overall energy efficiency of nearly 10%, close to the value needed for commercial viability. This preview provides a technological context for this advancement and discusses needed next steps.

The intertropical convergence zone (ITCZ) is a key circulation and precipitation feature in the tropics. There has been a large spread in the representation of the ITCZ in global weather and climate models for a long time, the reasons for which remain unclear. This manuscript presents a novel approach with which we disentangle different physical processes responsible for the changeable behavior of the ITCZ in numerical models. The diagnostic tool is based on a conceptual framework developed by Emanuel (2019) and allows for physically consistent estimates of convective mass flux and precipitation efficiency for simulations with explicit and parameterized convection. We apply our diagnostics to a set of tropical aquachannel experiments using the ICOsahedral Nonhydrostatic (ICON) model with horizontal grid resolution of 13 km and with various representations of deep and shallow convection. The channel length corresponds to the Earth's circumference and has rigid walls at 30° N/S. Zonally symmetric sea surface temperatures are prescribed. All four runs share overall similar rainfall patterns and dynamical structures. They simulate an ITCZ at the equator coinciding with the ascending branch of the Hadley circulation, descending branches at 15° N/S with subtropical jets and easterly trade wind belts straddling the ITCZ. Differences are largest between runs with and without parameterized deep convection. With explicit deep convection, rainfall in the ITCZ increases by 35 % and the Hadley circulation as well as surface winds become stronger. Our diagnostic framework reveals that boundary-layer quasi-equilibrium is a key to physically understanding those differences. The stronger surface horizontal winds with explicit deep convection essentially enhance surface enthalpy fluxes and thus perturb quasi-equilibrium in the boundary layer. This is balanced by increasing convective downdraft mass flux that carries low moist static energy from the lower troposphere into the boundary layer. The downdraft strength is proportional to convective updraft mass flux, which is closely linked to rainfall, since – somewhat surprisingly – the convective treatment does not appear to influence precipitation efficiency significantly. Changes in radiative cooling are largely compensated by changes in dry stability, leading to little impact on rainfall. The results highlight the utility of our diagnostics to pinpoint processes important for rainfall differences between models, suggesting applicability for global climate model intercomparison projects. [ABSTRACT FROM AUTHOR]

We successfully realized world first 77‐inch transparent flexible OLED display with Ultra High Definition (UHD) resolution, which can be rolled up to a radius of 80 mm with a transmittance of 40%. The process flow and key technologies to fabricate a large size transparent flexible OLED panel will be discussed. [ABSTRACT FROM AUTHOR]

The cathode material, high Nickel content Ni 0.7 Co 0.2 Mn 0.1 (NCM), was synthesized by coprecipitation with NH₄OH used as a complexing agent. The prepared materials are made in the formation of spherical particles of Li(Ni 0.7 Co 0.2 Mn 0.1 )O₂ of several micrometers in diameter. Al₂O₃ was coated by an impregnation method and its content was gradually increased to 1, 2 and 5 wt%. As a result, 1 wt% coated Al₂O₃ compared to pristine NCM exhibited 82% and 80% retention rates at 5 C and 1 wt% Al₂O₃ coated NCM recovery at 0.2 C after 5 C showed 100%. In addition, capacity retention of 1 wt% NCM+Al gently decreased in 100 cycle life characteristics, and capacity retention of 95% or more was confirmed.

Superior chemical sensing performance of black phosphorus (BP) is demonstrated by comparison with MoS2 and graphene. Dynamic sensing measurements of multichannel detection show that BP displays highly sensitive, selective, and fast-responsive NO2 sensing performance compared to the other representative 2D sensing materials., (© 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)