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Bioinspired smart surfaces, such as slippery liquid‐infused porous surfaces (SLIPS), have garnered significant attention due to their efficacy in self‐cleaning, antifouling, and antibacterial applications. Despite their advantages, SLIPS exhibit limitations such as compromised transparency, insufficient stability, and limited slippery performance, which have hindered their widespread practical use. To address these challenges, this article proposes a rational design utilizing a void‐centered poly(vinylidene fluoride‐co‐hexafluoropropylene) (PVDF) membrane for slippery liquid‐infused porous surfaces with exceptional flexibility, transparency, durability, and superior slippery performance. These advancements promise to enhance high‐performance, self‐cleaning, and antifogging coatings. The membranes, featuring large‐area, thickness‐customizable void‐centered PVDF, are fabricated through a two‐step process involving phase separation and selective etching. The utilization of PVDF polymer, which has a refractive index similar to that of silicon‐based lubricant oil, enhances transparency, while macrovoids positioned at the membrane's center, acting as oil reservoirs, improve the stability and performance of the SLIPS surfaces. Experimental findings demonstrate remarkable transparency of up to 93% in the visible light range and a lubricant oil uptake of 2.32 at a porosity of 70%. Moreover, the developed SLIPS exhibit outstanding durability, maintaining slippery performance with sliding angles of <10° following exposure to either 400 consecutive droplets or aging for up to 40 days. This study significantly contributes to the development of future SLIPS, particularly for applications such as antifogging coatings on vehicle glass and solar panels, and self‐cleaning surfaces. [ABSTRACT FROM AUTHOR]

The widespread use of single‐use plastic food wrapping and drinking straws has led to significant plastic and microplastic pollution, threatening environmental sustainability and human health. This study aims to provide sustainable alternatives by improving starch‐based biofilms' mechanical properties and water resistance for food wrapping and edible drinking straws. We modified starch with chitosan, raw seaweed, and sodium tripolyphosphate (STPP) to enhance these biofilms. Our results show that the optimal proportion of chitosan, combined with varying seaweed and STPP content, significantly improves the biofilms' properties. The developed starch‐based biofilms offer an eco‐friendly and sustainable alternative to single‐use plastic, with the potential for large‐scale, cost‐effective production. Highlights: Novel edible starch‐based biofilms were successfully prepared.The biofilms made from renewable FDA‐approved edible materials.Biofilms showed improved mechanical properties and water resistance.The biofilms exhibited non‐toxic and antimicrobial properties.Biofilms offer alternatives to single‐use plastic for food wrapping. [ABSTRACT FROM AUTHOR]

The disposal of plastic foam, mostly composed of polystyrene, poses significant environmental challenges due to its high popularity, slow degradation, and low cost. To address this problem, recycling polystyrene foam waste (PF) has emerged as a promising solution to reduce plastic pollution. This paper presents a novel approach to mass‐produce highly ordered, porous honeycomb‐patterned film (hc‐film) using wasted PF as the raw material. The hc‐film is produced using an improved phase separation (IPS) method that utilizes methanol as a suitable pore inducer and template droplet stabilizer. Methanol provides the hc‐film with customizable features such as pore ordering, size, and separation. The freestanding hc‐film, achieved by adopting a water‐soluble polystyrene sulfonate as a scarified layer, can be transferred and utilized as a flexible mold to pattern various solid substrates with complicated surface morphologies using the pre‐impregnated technique. This study demonstrates the potential of this cost‐effective and efficient approach for various applications, such as super/anti‐wetting surfaces, microelectronics, optical devices, sensors, and nanogenerators. [ABSTRACT FROM AUTHOR]

Summary: Porous graphene oxide‐surfactant/poly(lactic acid) (GO‐S/PLA) nanocomposite film with highly ordered hexagonal pore arrangement was fabricated via a combination of ionic interaction‐supported GO dispersion and the improved phase separation method. First, a flat nanocomposite film is prepared by coating a well‐dispersed GO‐S/PLA solution on a solid substrate. Subsequently, the film is exposed to a mixture of chloroform and methanol as a suitable volatile solvent/nonsolvent pair for both PLA and surfactant‐grafted GO sheets. A monolayer of honeycomb patterns is spontaneously formed on the nanocomposite surface after complete evaporation of liquids under normal air conditions. Methanol plays a crucial role in effectively inducing and controlling the ordered honeycomb structures. The pore array features, which include pore diameter and pore density, are tuned by adjusting methanol content. Moreover, the patterned GO‐S/PLA nanocomposite demonstrates as an efficient electrification component for high‐performance triboelectric nanogenerator (TENG) owing to a large surface area and abundant electron‐donating groups of GO sheets. A new TENG is composed of the honeycomb GO‐S/PLA (hc‐GO‐S/PLA) and its replica of microdome‐patterned polydimethylsiloxane (md‐PDMS), as a pair of tribo‐components with antagonistic friction surfaces. As a result, it can generate an output power of 0.54 mW cm−2 which is 8.6 times higher than that of TENG with a flat surface and without GO additives. We believe that hc‐GO‐S/PLA nanocomposite has potential applications in biotechnology, optics, and catalyst fields. [ABSTRACT FROM AUTHOR]

Most mechanical energy harvesters produce only small amounts of electrical power from extremely low‐frequency input motions and immediately stop generating electricity when mechanical kinetic energy is exhausted. Here, a steady, long‐lasting and power‐boosted triboelectric nanogenerator is reported that can efficiently harvest from extremely low‐frequency irregular motions of less than 0.1 Hz by utilizing an escapement mechanism and frequency up‐conversion device. The escapement mechanism‐based triboelectric nanogenerator (EM‐TENG) consists of a mechanical energy storage spring, escapement mechanism and a torsional resonator for regular operation and frequency up‐conversion. In addition, the micro‐patterned alternating dielectric surfaces of Nylon and polytetrafluoroethylene (PTFE) and the comb‐type rotator significantly improve the output performance of the rotational EM‐TENG, increasing the current density level approximately 4.2 times compared to flat surfaces. Under an input frequency of 0.067 Hz, the EM‐TENG produces an open circuit voltage of 320 V and a short‐circuit current density of 0.59 mA m‐2. Most importantly, the EM‐TENG can produce long‐lasting and steady output power for 110 s (22 times) under only 5 s of input motion. Therefore, the EM‐TENG might pave the way to effectively harvest energy from extremely low‐frequency motions in nature, such as human motion, structural vibration and ocean waves. [ABSTRACT FROM AUTHOR]

Abstract: This study reports the fabrication of a Petri dish patterned with cylindrical micro‐cavities that are produced using a one‐step solvent‐immersion phase‐separation process. The developed 3D honeycomb Petri dish is coated with a Au film through a sputtering method to be an efficient Au‐coated FTO‐free electrode for quantum‐dot‐sensitized solar cells. Due to the high specific active surface area of the electrode with the Au‐coated honeycomb structure, the energy conversion efficiency of devices that use this electrode is 5.2 % compared to 4.4 and 4.7 % by devices using an Au‐coated flat Petri dish and an Au‐coated FTO electrode, respectively. This design strategy offers excellent potential for the fabrication of highly efficient counter electrodes with FTO‐free substrates of flexible photovoltaic devices. [ABSTRACT FROM AUTHOR]

This study reports the fabrication of a Petri dish patterned with cylindrical micro-cavities that are produced using a one-step solvent-immersion phase-separation process. The developed 3D honeycomb Petri dish is coated with a Au film through a sputtering method to be an efficient Au-coated FTO-free electrode for quantum-dot-sensitized solar cells. Due to the high specific active surface area of the electrode with the Au-coated honeycomb structure, the energy conversion efficiency of devices that use this electrode is 5.2 % compared to 4.4 and 4.7 % by devices using an Au-coated flat Petri dish and an Au-coated FTO electrode, respectively. This design strategy offers excellent potential for the fabrication of highly efficient counter electrodes with FTO-free substrates of flexible photovoltaic devices., (© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)