Over the past few years, the scientific community, as well as the world's coatings industry has seen the introduction of oxide/polymer-based superhydrophobic surfaces and coatings with exceptional water repellency. Online videos have caught the public's imagination by showing people walking through mud puddles without getting their tennis shoes wet or muddy, and water literally flying off coated surfaces. This article attempts to explain the basics of this behavior and to discuss and explain the latest superhydrophobic technological breakthroughs. Since superhydrophobic surfaces and coatings can fundamentally change how water interacts with surfaces, and the fact that earth is a water world, it can legitimately be said that this technology has the potential to literally change the world.

Realizing the commercialization of high-performance and robust perovskite solar cells urgently requires the development of economically scalable processing techniques. Here we report a highthroughput ultrasonic spray-coating (USC) process capable of fabricating perovskite film-based solar cells on glass substrates with power conversion efficiency (PCE) as high as 13%.Perovskite films with high uniformity, crystallinity, and surface coverage are obtained in a single step. Moreover, we report USC processing on TiO 2 /ITO-coated polyethylene terephthalate (PET) substrates to realize flexible perovskite solar cells with PCE as high as 8.1% that are robust under mechanical stress. In this case, a photonic curing technique was used to achieve a highlyconductive TiO 2 layer on flexible PET substrates for the first time. The high device performance and reliability obtained by this combination of USC processing with optical curing appears very promising for roll-to-roll manufacturing of high-efficiency, flexible perovskite solar cells. -halide perovskite solar cells, with power conversion efficiencies (PCEs) rapidly reaching circa 20%, 1-3 are one of the most promising, next-generation photovoltaic technologies due to their excellent material properties, including long carrier diffusion lengths 4 and large absorption coefficients. 5 To achieve high-quality perovskite films, a variety of deposition techniques, such as thermal evaporation, 6-8 single-step spin-coating, 9,10 layer-by-layer or two-step coating, 11,12 and vapor-assisted 13 processes have been developed. However, one major disadvantage of most laboratory-scale techniques is that they are incompatible with lowcost, roll-to-roll processing envisioned for large-scale manufacturing. Existing scalable processing techniques include ink-jet printing, slot-die coating, blade-coating, screen printing, and ultrasonic spray-coating. 14-21Among these cost-effective roll-to-roll compatible processes, ultrasonic spray-coating (USC) is one of the most promising that has been successfully exploited for the fabrication of various organic electronic devices including light emitting diodes, 22 photovoltaics, 23,24 photodetectors, 25 and field-effect transistors. 26 The overall advantage of USC is its ability to simultaneously provide high throughput, better control over directional deposition, efficient use of materials, uniform film coverage, compatibility with variety of substrates, with the potential for the deposition of continuous layers without dissolution of underlying layers. 23,[26][27][28] Recently, the USC process was demonstrated to deposit perovskite thin films on glass substrates, and the resulting devices showed an average PCE of 7. 8%. 29 However, considering the diverse application potential for thin film perovskites, it is highly important to demonstrate the fabrication of high-performance devices on light-weight and flexible substrates using scalable techniques. So far, one major challenge for the fabrication of solar cells on plastic substrates is their ...

Herein we report on the synthesis and characterization of MXene–polyacrylamide (PAM) nanocomposite films. The as-prepared composites are flexible and the conductivity was increased significantly to 3.3 × 10−2S m−1with only 6 wt% MXene loading.

We investigate the electrical properties of composite materials prepared as nano-and sub-micron-scale metal-oxide particles embedded in a commercial resin. The filler particles are barium titanate and calcium copper titanate. The physical and structural characteristics of the constituents and the fabricated composites are reported. Electrical characterization of the composite samples is performed using time-and frequency-domain dielectric spectroscopy techniques. The electrical breakdown strength of samples with nano-and sub-micron-sized particles have better electrical insulation properties than the unfilled resin.