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Zinc oxide (ZnO) has been widely acknowledged as a highly effective photocatalyst for the degradation of organic pollutants. In this study, we presented silver nanoparticles (AgNPs) embedded ZnO foam photocatalyst (Ag−ZnO) on glass substrates by the chemical bath in‐situ co‐deposition method. Our findings demonstrat that at low Ag‐loading content, metallic Ag0 NPs are embedded within the ZnO foam, while at high Ag‐loading content, they accumulates increasingly from inside to the surface of the foam. With the increase of AgNPs loading from 0.1 mM to 1.5 mM, the absorption of Ag−ZnO foams in the visible light region gradually enhances. The photocatalytic degradation efficiency of rhodamine B (RhB) is the highest in Ag−ZnO foams when the Ag loading concentration reaches 0.8 mM, suggesting an optimal content of Ag for enhanced performance. This trend is attributed to the photo‐induced charge transfer behavior of Ag−ZnO samples. The AgNPs embedded inside the ZnO foam enhance the separation of photo‐induced charges and prevent their recombination. As a result, Ag−ZnO(0.8 mM) foam with more photo‐induced holes participate in the photocatalytic reaction, leading to a remarkably high photocatalytic activity. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Inverted perovskite solar cells (PerSCs) are a highly promising candidate in the photovoltaic field due to their low‐temperature fabrication process, negligible hysteresis, and easy integration with Si‐based solar cells. A cathode interlayer (CIL) is necessary in the development of inverted devices to reduce the trap density and energy barrier between the electron transport layer (ETL) and the electrode. However, most CILs are highly thickness‐sensitive due to low conductivity and poor film‐forming. In this study, we report on a self‐doping perylene imide‐based ionene polymer (PNPDIN) used as CIL material to modify electrode in inverted PerSCs. PNPDIN exhibits high conductivity and a good solubility in polar solvent, which results in an improved power conversion efficiency (PCE) from 10.05% (device without a CIL) to 16.97%. When the blend of PNPDIN and Bphen was used as a mixed CIL, the PCE of PerSCs can be further increased to 21.28% owing to the excellent morphology and matched energy level. More importantly, the PCE of the device is highly tolerant to the thickness of the mixed CIL, which benefited from the high conductivity of PNPDIN. This development is expected to provide an excellent mixed CIL material for roll‐to‐roll processing efficient and stable inverted PerSCs. [ABSTRACT FROM AUTHOR]

Photoelectrochemical (PEC) water splitting has attracted strong interest as sustainable technology by converting solar energy into hydrogen. The semiconductor photoelectrodes play an important role to increase the solar‐to‐hydrogen conversion efficiency. Bismuth vanadate (BiVO4) is an excellent candidate as a photoanode material for PEC water oxidation because of its visible light absorption, suitable band edge location, high stability and low cost. However, BiVO4 alone may undergo short carrier diffusion length, rapid recombination of photo‐induced charge carriers and photocorrosion. The heterojunction strategy established by combining two or more materials has provided an outstanding technique to address these issues. This Review focuses on recent important works with respect to BiVO4 heterojunction photoanodes for PEC water oxidation reactions, including interface junction and surface functional junction formation. Additionally, challenges faced and prospects for future research on BiVO4 heterojunction photoanodes in the field of solar‐to‐hydrogen conversion are proposed. [ABSTRACT FROM AUTHOR]

It is still a challenge to prepare 2D ultrathin ZnO in a simple method, especially for the in‐situ growth of 2D ultrathin ZnO on different substrates. Herein the ZnO foam with high specific surface area is successfully assembled in situ from graphene‐like ultrathin nanosheet on various substrates, including rigid fluoride doped tin oxide, Ni foam, and flexible indium tin oxide, carbon cloth, etc. The thickness of graphene‐like nanosheet is just ≈1.5 nm. The results reveal that the specific surface area of ZnO nanosheets is 90.7 m2 g−1. The high specific surface area of the hydrophilic ZnO foam and its in‐situ growth characteristic make it promising water channel in solar‐driven interfacial water evaporation system. By using a flexible carbon cloth/ZnO foam (C‐ZnO) Janus absorber, a high rate of water evaporation (2.4 kg m−2 h−1), which is 4.6 times higher than that of natural evaporation is demonstrated. This work provides a new method in the design of ZnO ultrathin nanosheets, what's more, the facile growth of the ZnO foam on various substrates make it possible for the application in optoelectronic devices. [ABSTRACT FROM AUTHOR]

Tribological behaviors of three typical kinds of diamond‐like carbon (DLC) films (a‐C, a‐C:Cr, and a‐C:H) in sulfuric acid and sodium hydroxide solutions were investigated. The a‐C film showed the lowest stable coefficients of friction (COF) in both sulfuric acid and sodium hydroxide solutions but the worst wear resistance in sulfuric acid solution. The a‐C:H film showed the highest COF in sulfuric acid solution and the best wear resistance in both sulfuric acid and sodium hydroxide solutions. The a‐C:Cr film exhibited superior comprehensive tribological performance in sulfuric acid solution, while in sodium hydroxide solution, high COF and very poor wear resistance was observed. What is more, friction and wear mechanism was revealed by investigating the friction‐induced material evolutions on the sliding surface. [ABSTRACT FROM AUTHOR]

Electronic skin (e‐skin) has attracted extensive attention owing to its potential application in biomedical sensors, intelligent robots, and bionic prostheses. To imitate better or even surmount the perceptive capabilities of human skin, multifunctional e‐skin is an important trend in the field. A novel stable perovskite intermediate gel (PIGel) is obtained during the MA2SnI6 perovskite crystallization process. This Sn‐based PIGel exhibits good conductivity and outstanding wettability on different polymer substrates. Based on these properties, it is successfully applied to the field of e‐skin. Flexible and stretchable multifunctional e‐skin sensors are developed based on it. Stretching, finger bending, voice recognition, pulse monitoring, temperature, and electricity response are achieved in one e‐skin device. In addition, the MA2SnI6 perovskite single crystal is prepared by solvent engineering. The formation mechanism of the PIGel and MA2SnI6 single crystal is studied in detail. This work broadens the selection range of sensing materials for e‐skin and paves the way to achieve multifunctional sensors with the facile fabrication process. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Inverted perovskite solar cells (PerSCs) are a highly promising candidate in the photovoltaic field due to their low‐temperature fabrication process, negligible hysteresis, and easy integration with Si‐based solar cells. A cathode interlayer (CIL) is necessary in the development of inverted devices to reduce the trap density and energy barrier between the electron transport layer (ETL) and the electrode. However, most CILs are highly thickness‐sensitive due to low conductivity and poor film‐forming. In this study, we report on a self‐doping perylene imide‐based ionene polymer (PNPDIN) used as CIL material to modify electrode in inverted PerSCs. PNPDIN exhibits high conductivity and a good solubility in polar solvent, which results in an improved power conversion efficiency (PCE) from 10.05% (device without a CIL) to 16.97%. When the blend of PNPDIN and Bphen was used as a mixed CIL, the PCE of PerSCs can be further increased to 21.28% owing to the excellent morphology and matched energy level. More importantly, the PCE of the device is highly tolerant to the thickness of the mixed CIL, which benefited from the high conductivity of PNPDIN. This development is expected to provide an excellent mixed CIL material for roll‐to‐roll processing efficient and stable inverted PerSCs. [ABSTRACT FROM AUTHOR]

Super-thick diamond-like carbon (DLC) film is a potential protective coating in corrosive environments. In the present work, three kinds of DLC films whose thickness and modulation periods are 4 µm and 3, 21 µm and 17 and 21 µm and 7, respectively, were fabricated on stainless steel. The effect of different thickness and modulation periods on corrosion and tribocorrosion behaviour of the DLC-coating stainless steel was investigated in 3.5 wt% NaCl aqueous solution by a ball-on-flat tribometer equipped with a three-electrode electrochemical cell. The DLC-coating stainless steel served as a working electrode, and its OCP and potentiodynamic polarization were monitored before and during rubbing. The wear-corrosion mechanism of the DLC films was investigated by SEM. The results showed that the increasing thickness can prolong significantly lifetime of DLC films in NaCl aqueous solution. In particular, the modulation period has a significant impact on the tribocorrosion resistance of the DLC super-thick films. The study suggested that the increasing thickness of compressive stress layer could suppress film damage by reducing crack propagation rate. Thus, the super-thick DLC film with thickness of 21 µm and 7 periods presented the best tribocorrosion resistance among all studied films. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

This study focuses on incorporating liquid molecules, different from the bulk solution, into the immobilized enzyme carrier to regulate the distribution effect and diffusion‐limiting impact of the carrier's microenvironment for substrates, which generally is difficult to achieve due to the instability of the materials with liquid inclusions. A freestanding liquid‐holding particle carrier, with bi‐component hydrophobic ionic liquid gel microspheres with poly (glycidyl methacrylate) as the network and 1‐butyl‐3‐methylimidazolium hexafluorophosphate as the dispersing medium, is proposed, which is stable in air aqueous solution, and can extract proteins and organic small molecules into its interior due to the mobility of its dispersing medium. Horseradish peroxidase is covalently immobilized into the microspheres, forming a liquid compartment enzyme microreactor. The microreactor exhibits superior stability, enzymatic activity, and catalytic performance for Basic Orange II degradation compared to free enzyme and liquid‐free immobilized enzymes. This is attributed to the biocompatibility of the ionic liquid, its role in substrate enrichment in its interior, and its rapid mass transfer capability. This contribution shows the effectiveness of regulating the carrier's microenvironment with liquid molecules, offering fresh perspectives and strategies for enzyme technology. [ABSTRACT FROM AUTHOR]