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As a promising energy storage system, sodium-ion batteries face challenges related to the stability and high-rate capability of their electrode materials, especially carbon, which is the most studied anode. Previous studies have demonstrated that three-dimensional architectures composed of porous carbon materials with high electrical conductivity have the potential to enhance the storage performance of sodium-ion batteries. Here, high-level N/O heteroatoms-doped carbonaceous flowers with hierarchical pore architecture are synthesized through the direct pyrolysis of homemade bipyridine-coordinated polymers. The carbonaceous flowers could provide effective transport pathways for electrons/ions, thus allowing for extraordinary storage properties in sodium-ion batteries. As a consequence, sodium-ion battery anodes made of carbonaceous flowers exhibit outstanding electrochemical features, such as high reversible capacity (329 mAh g−1 at 30 mA g−1), superior rate capability (94 mAh g−1 at 5000 mA g−1), and ultralong cycle lifetimes (capacity retention rate of 89.4% after 1300 cycles at 200 mA g−1). To better investigate the sodium insertion/extraction-related electrochemical processes, the cycled anodes are experimentally analyzed with scanning electron microscopy and transmission electron microscopy. The feasibility of the carbonaceous flowers as anode materials was further investigated using a commercial Na3V2(PO4)3 cathode for sodium-ion full batteries. All these findings indicate that carbonaceous flowers may possess great potential as advanced materials for next-generation energy storage applications.

Lithium-ion batteries with high reversible capacity, high-rate capability, and extended cycle life are vital for future consumer electronics and renewable energy storage. There is a great deal of interest in developing novel types of carbonaceous materials to boost lithium storage properties due to the inadequate properties of conventional graphite anodes. In this study, we describe a facile and low-cost approach for the synthesis of oxygen-doped hierarchically porous carbons with partially graphitic nanolayers (Alg-C) from pyrolyzed Na-alginate biopolymers without resorting to any kind of activation step. The obtained Alg-C samples were analyzed using various techniques, such as X-ray diffraction, Raman, X-ray photoelectron spectroscopy, scanning electron microscope, and transmission electron microscope, to determine their structure and morphology. When serving as lithium storage anodes, the as-prepared Alg-C electrodes have outstanding electrochemical features, such as a high-rate capability (120 mAh g−1 at 3000 mA g−1) and extended cycling lifetimes over 5000 cycles. The post-cycle morphologies ultimately provide evidence of the distinct structural characteristics of the Alg-C electrodes. These preliminary findings suggest that alginate-derived carbonaceous materials may have intensive potential for next-generation energy storage and other related applications.

Eco-friendly, efficient fireproof cotton fabrics were prepared by a feasible chemical grafting of phytic acid (PA). The treated cotton fabrics (COTP) exhibited excellent thermal stability and flame resistance with limiting oxygen index (LOI) of 42.5%. Compared with other fireproof cotton fabrics, COTP displayed outstanding washing durability, the LOI maintained at 28.3% after 50 laundering cycles. Vertical burning test and cone calorimetry demonstrated self-extinguishing behavior and significantly improved flame retardancy of COTP. The peak heat release rate and the total heat release of COTP3-90 was notably declined by 65.5 and 71.4%, respectively. Moreover, lower smoke production and release were found with reduction in total smoke production of 12.5% and total smoke rate of 18.8% compared with untreated cotton fabric. The improved flame retardancy of COTP was speculated that PA catalyzed cellulose dehydration and carbonization to facilitate the formation of residual char, reduce the release of flammable gases and heat/mass transfer.

Omnidirectional and broadband antireflection (AR) self-cleaning coatings are crucial for the performance enhancement of photovoltaic (PV) modules. Herein, we demonstrate biomimetic moth-eye structures on glass through inductively coupled plasma (ICP) etching process using thermal dewetted copper nanoparticles as the masks. Moreover, the etched glasses are chemically treated to strengthen the nanostructures. The moth-eye glass exhibits excellent AR effects with a reflectance below 3% over the wavelength range from 570 to 950 nm. As the incident angles of the light increasing from 0o to 60o, the relative improvement of the power conversion efficiency (PCE) of PV module with moth-eye glass produces a dramatically increases from 4.6% to 9.9%, compared with that of PV modules with flat glass. Additionally, the moth-eye glass also possesses superhydrophilic self-cleaning and antifogging abilities, which are attractive for outdoor applications.

Complementary metal oxide semiconductor (CMOS) image sensors (CIS) are being widely used in digital video cameras, web cameras, digital single lens reflex camera (DSLR), smart phones and so on, owing to their high level of integration, random accessibility, and low-power operation. It needs to be installed with the cover glass in practical applications to protect the sensor from damage, mechanical issues, and environmental conditions, which, however, limits the accuracy and usability of the sensor due to the reflection in the optical path from air-to-cover glass-to-air. In this work, the flexible 3D nanocone anti-reflection (AR) film with controlled aspect ratio was firstly employed to reduce the light reflection at air/cover glass/air interfaces by directly attaching onto the front and rear sides of the CIS cover glass. As both the front and rear sides of cover glass were coated by the AR film, the output image quality was found to be improved with external quantum efficiency increased by 7%, compared with that without AR film. The mean digital data value, root-mean-square contrast, and dynamic range are increased by 45.14%, 38.61% and 57, respectively, for the output image with AR films. These results provide a novel and facile pathway to improve the CIS performance and also could be extended to rational design of other image sensors and optoelectronic devices.

Robust and sustainable cellulose composite aerogels were prepared by incorporating MgAl-layered double hydroxide (MgAl-LDH) as green nanofillers and flame retardants. Two series of aerogels combining MgAl-CO3 LDH (MA-C) and MgAl-H2PO4 LDH (MA-P) were achieved, in which both MA-C and MA-P were uniformly dispersed in cellulose substances. The cellulose composite aerogels with 1.8 wt% of MA-C (denoted as CAC) and MA-P (denoted as CAP) displayed excellent mechanical properties, increased by 2.6 and 2.8 times compared with neat cellulose aerogels (CA), respectively. The peak of heat release rate (PHRR) of CAC and CAP reduced by 41 % and 50 % compared with the neat one, respectively, demonstrating the outstanding flame retardancy. The reduction in smoke production ratio (SPR) was 79 % for CAC and 75 % for CAP, respectively, indicating enhanced smoke suppression performance. Therefore, the high performance flame-retardant cellulose composite aerogels exhibit an application prospect in green advanced engineering field.