Carbon fiber is a good candidate in various applications, including in the military, structural, sports equipment, energy storage, and infrastructure. Coloring of carbon fiber has been a big challenge for decades due to their high degrees of crystallization and insufficient chemical affinity to dyes. Here, multicolored carbon fiber fabrics are fabricated using a feasible and effective atomic layer deposition (ALD) technique. The vibrant and uniform structural colors originating from thin-film interference is simply regulated by controlling the thickness of conformal TiO coatings on the surface of black carbon fibers. Impressively, the colorful coatings show excellent laundering durability, which can endure 50 cycles of domestic launderings. Moreover, the mechanical properties only drop off slightly after coloring. Overall, these results open an alternative avenue for development of TiO nanostructured films with multifunctional features grown using ALD technologies. This technology is speculated to have potential applications in various fields such as color engineering and radiation-proof fabrics and will further guide material design for future innovations in functional optical and color-display devices. More importantly, this research demonstrates a route for the coloring of black carbon fiber-based materials with vibrant colors.

In this study, silk fiber was successfully modified via the application of a nanoscale titania coating using atomic layer deposition (ALD), with titanium tetraisopropoxide (TIP) and water as precursors at 100 °C. Scanning electron microscopy, X-ray energy dispersive spectroscopy, X-ray photoelectron spectroscopy, transmission electron microscope, and field emission scanning electron microscope results demonstrated that uniform and conformal titania coatings were deposited onto the silk fiber. The thermal and mechanical properties of the TiO2 silk fiber were then investigated. The results showed that the thermal stability and mechanical properties of this material were superior to those of the uncoated substance. Furthermore, the titania ALD process provided the silk fiber with excellent protection against UV radiation. Specifically, the TiO2-coated silk fibers exhibited significant increases in UV absorbance, considerably less yellowing, and greatly enhanced mechanical properties compared with the uncoated silk fiber after UV exposure.

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In this study we design and construct high-efficiency, low-cost, highly stable, hole-conductor-free, solid-state perovskite solar cells, with TiO2 as the electron transport layer (ETL) and carbon as the hole collection layer, in ambient air. First, uniform, pinhole-free TiO2 films of various thicknesses were deposited on fluorine-doped tin oxide (FTO) electrodes by atomic layer deposition (ALD) technology. Based on these TiO2 films, a series of hole-conductor-free perovskite solar cells (PSCs) with carbon as the counter electrode were fabricated in ambient air, and the effect of thickness of TiO2 compact film on the device performance was investigated in detail. It was found that the performance of PSCs depends on the thickness of the compact layer due to the difference in surface roughness, transmittance, charge transport resistance, electron-hole recombination rate, and the charge lifetime. The best-performance devices based on optimized TiO2 compact film (by 2000 cycles ALD) can achieve power conversion efficiencies (PCEs) of as high as 7.82%. Furthermore, they can maintain over 96% of their initial PCE after 651 h (about 1 month) storage in ambient air, thus exhibiting excellent long-term stability.

Traditionally, spatially-resolved photoluminescence (PL) has been performed using a point-by-point scan mode with both excitation and detection occurring at the same spatial location. But with the availability of high quality detector arrays like CCDs, an imaging mode has become popular for performing spatially-resolved PL. By illuminating the entire area of interest and collecting the data simultaneously from all spatial locations, the measurement efficiency can be greatly improved. However, this new approach has proceeded under the implicit assumption of comparable spatial resolution. We show here that when carrier diffusion is present, the spatial resolution can actually differ substantially between the two modes, with the less efficient scan mode being far superior. We apply both techniques in investigation of defects in a GaAs epilayer – where isolated singlet and doublet dislocations can be identified. A superposition principle is developed for solving the diffusion equation to extract the intrinsic carrier diffusion length, which can be applied to a system with arbitrarily distributed defects. The understanding derived from this work is significant for a broad range of problems in physics and beyond (for instance biology) – whenever the dynamics of generation, diffusion, and annihilation of species can be probed with either measurement mode.

Reducing energy consumption is one of the major concerns in modern building design and construction because buildings account for ≈40% of the total energy consumption in modern society. Among various technologies for saving energy, electrochromic smart windows are considered as a highly promising one. Except for the application in saving energy, electrochromism has also attracted extensive attention in many other fields, such as, anti‐glare rearview mirrors, displays, military camouflage, flexible wearable fabric, etc. However, there are still many challenges needed to be solved, such as, the response rate and durability of electrochromic materials (ECMs). The transmission rate of ions in ECMs determines the response rate of the whole electrochromic device. Besides, the embedding depth and total amount of ions directly affect the contrast, durability, and coloration efficiency of ECMs. It is crucial to select suitable electrolyte ions to obtain high‐efficiency ECMs. Here, the challenges in ECMs based on ions insertion/extraction are presented, which are focused on advanced nanostructured ECMs’ design and electrochromic devices’ practical application. Recent advances in ECMs are presented to discuss the important questions, which are especially focused on the connection between suitable ions and advanced nanostructural ECMs. Finally, a perspective for next‐generation electrochromic devices is presented.

applications. Recently, bionic fluffy fabrics learning from many animals, such as crickets and spiders, were reported to fabricate airflow sensors but usually exhibited low sensitivity and slow response speed against different airflows. [9,10] Therefore, the rational design and controllable fabrication of airflow sensors are urgently needed to tackle their issues of poor performance.For piezoresistive materials, sufficient deformation under external forces is the prerequisite for causing resistance variations, which calls for the excellent flexibility of the component materials. Besides, lightweight materials are easy to change their states of motion due to their low inertia, ensuring a fast response to external stimuli. For composite-based sensors, the interfacial areas within the composites should also be reduced because the interfaces often behave like capacitors under external electrical fields, [11] which inevitably causes a decline in the response speed of sensors owing to the charging-discharging processes. Therefore, from the perspective of material selection, flexible and lightweight materials with small interfacial areas show more advantages in fabricating highly sensitive and responsive piezoresistive sensors.Carbon nanotubes (CNTs) are supposed to be ideal candidates for fabricating high-performance piezoresistive airflow sensors because of their intrinsic properties, such as nanosized diameters, high aspect ratio and flexibility, low density, and excellent mechanical and electrical properties, [12,13] which fully meet the requirements for airflow sensors. However, the previous attempts to incorporate CNTs with other materials for making airflow sensors usually produced mixed bulky structures with declined mechanical properties, thus degrading their performance as sensors. [14][15][16][17][18] For example, the response time of many CNT-based sensors generally ranges from one to several seconds, [9,[19][20][21] which is far inferior to the expected performance of individual CNT-based sensors. [22][23][24] In previous studies, carbonized silk fabric (CSF) decorated with fluffylike CNTs were developed as piezoresistive airflow sensors, of which the sensing performance was simultaneously determined by the properties of CSF and CNTs. [9] Although the CNT assembly with a foam-like structure was capable of sensing very mild airflows, its response time was ≈1.3 s, which could High-performance airflow sensors are in great demand in numerous fields but still face many challenges, such as slow response speed, low sensitivity, large detection threshold, and narrow sensing range. Carbon nanotubes (CNTs) exhibit many advantages in fabricating airflow sensors due to their nanoscale diameters, excellent mechanical and electrical properties, and so on. However, the intrinsic extraordinary properties of CNTs are not fully exhibited in previously reported CNT-based airflow sensors due to the mixed structures of macroscale CNT assemblies. Herein, this article presents suspended CNT networks (SCNTNs) as high-performance a...

To obtain a hydrophobic surface, TiO2 coatings are deposited on the surface of silk fabric using atomic layer deposition (ALD) to realize a hierarchical roughness structure. The surface morphology and topography, structure, and wettability properties of bare silk fabric and TiO2-coated silk fabrics thus prepared are evaluated using scanning electron microscopy (SEM), field-emission scanning electron microscopy (FESEM), scanning probe microscope (SPM), X-ray diffraction (XRD), static water contact angles (WCAs), and roll-off angles, respectively. The surfaces of the silk fabrics with the TiO2 coatings exhibit higher surface roughnesses compared with those of the bare silk fabric. Importantly, the hydrophobic and laundering durability properties of the TiO2-coated silk fabrics are largely improved by increasing the thickness of the ALD TiO2 coating. Meanwhile, the ALD process has a litter effect on the service performance of silk fabric. Overall, TiO2 coating using an ALD process is recognized as a promising approach to produce hydrophobic surfaces for elastic materials.