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In various fields, the innovation of optoelectronic devices crucially depends on flexible, transparent materials that shield against electromagnetic interference. Herein, the fabrication of flexible transparent electromagnetic interference shielding effectiveness (EMI SE) composite films on PET substrates is achieved using silver nanowires (Ag NWs) and two-dimensional nanosheets (Ti3C2Tx). The uniform Ag NWs with high aspect ratio as a basic conductive network are synthesized using a modified polyol method, which is further optimized through combining with two-dimensional multilayer MXene nanosheets. The Ag NW/MXene composite films acquire a sandwich structure after sequential layering of Ag NW/MXene, finalized by spin-coated PMMA layer. It is worth noting that the addition of MXene nanosheet can decrease surface roughness and increase conductivity via filling the gap of Ag NW network. The Ag NW4/MXene4 composite films with excellent photoelectric performance are suitable for the commercial applications considering the production costs. Furthermore, the fabricated Ag NW/MXene/PMMA composite films demonstrate exceptional flexibility, maintaining integrity after 10 000 continuous bending cycles, and exhibit remarkable stability under harsh conditions, specifically in environments of 80 °C and 80% relative humidity (RH) for duration of 30 days. By finely tuning the concentrations of Ag NW and MXene nanosheets, these composite films attain significant EMI SE level of 35 dB in the X-band. In the EMI shielding mechanism, the absorption component of the shielding effectiveness (SE) is shown to play an important role. The integration of MXene into the composite film markedly improves its EMI shielding effectiveness by boosting the conductivity of the Ag NW network. Furthermore, the multireflection originating from the inner MXene nanosheet is another pathway to promote the EMI shielding performance, which is always neglected for the thin films. Taken together, the introduction and understanding of MXene into Ag NW transparent films provide inspiration for the development of advanced EMI shielding materials for wide applications. [ABSTRACT FROM AUTHOR]

The hydrogen evolution reaction (HER) must use a catalyst to reduce the overpotential and accelerate the chemical reaction of the electrolysis process. Pt stands out because of its very good catalytic properties. However, the extremely low content of Pt in the Earth's crust and the high price of Pt severely limit the large-scale use of this precious metal. In order to reduce the use of Pt and enhance catalytic activity, we designed a composite structure by combining the plasmon effect characteristics of Au with Pt particles. In this work, we investigated the synthesis and growth mechanism of Au@Pt nanostars with gold nanostars (Au NS) as the core, and explored the application efficiency of Au@Pt nanostars in photocatalysis. The Au NS were produced by a "one-step synthesis", and the Au@Pt nanostars were synthesized by growing Pt on the nanostar surface. More branched Au NS formed catalysts with Pt clusters for metal ionization enhancement. The catalytic activity of the structure was increased by the presence of Pt. The synergistic advantages of the heterogeneous composite nanostructures mean the structures have high photoelectrocatalysis activity at the edge and corner positions. Benefiting from the synergistic effect and the plasmon-induced accelerated molecular transformations, the Au@Pt nanostars manifest outstanding plasmon-enhanced electrochemical activity toward the HER with a low overpotential of 23.08 mV for achieving the current density of 10 mA cm−2, which surpasses the commercial Pt/C catalyst. At the same time, the Au NS also exhibit excellent photocatalytic performance with a smaller initial overpotential (ΔV = 9.03 mV) than that in the absence of light. This shows that the study of this structure can be used for the development and application of new energy and hydrogen energy. [ABSTRACT FROM AUTHOR]

Recently, flexible transparent conductive films have received widespread attention as important components in the field of organic electronics. Herein, we propose a method for directly constructing flexible transparent conductive films on curved surfaces using silver nanowires as the primary conductive material with the assistance of ethyl cellulose. The uniform transparent conductive film is produced by spray coating the silver nanowires on the curved surface with a curvature diameter of 5 cm. The average sheet resistance is approximately 18.9 Ω sq–1 with a transparency reaching 92.33%, and the standard deviation of the surface resistance is 1.1 Ω sq–1. The inclusion of ethyl cellulose prevents the aggregation of silver nanowires and allows their even distribution on the film surface, which is crucial for achieving a uniform and stable transparent conductive film. Through the analysis and comparison of different types of cellulose, such as methyl cellulose, ethyl cellulose, hydroxyethyl cellulose, hydroxypropyl cellulose, hydroxypropyl methyl cellulose, cellulose acetate, and cyanoethyl cellulose, a conclusion has been derived that only cellulose soluble in organic solvents can maintain a homogeneous distribution on the surface of the film without aggregation. Furthermore, changing the magnitude and sign of the curvature did not affect the uniformity of the film. The significant industrial potential of our approach lies in the direct construction of a uniformly transparent silver nanowire network on curved surfaces with applications spanning various fields. Specifically, it can be employed in the realm of electronics, catering to the needs of touchscreens in electronic displays, solar cells, and flexible electronic devices, such as flexible circuit boards. [ABSTRACT FROM AUTHOR]

Copper nanowire-based transparent conductive films have garnered extensive attention owing to their cost-effectiveness and comparable electrical properties. However, the inherent instability of copper nanowires (Cu NWs) has curtailed their extensive utility and applicability. Herein, we present durable Cu@Au NW/PET films exhibiting elevated photoelectric attributes and remarkable flexibility. After preparing Cu NWs, the purification operation allows the purity of the Cu NWs to reach about 98%. Subsequently, Cu@Au NWs/PET flexible transparent conductive films (FTCFs) were prepared through vacuum filtration of Cu NWs and direct treatment with chloroauric acid. The resulting Cu@Au NW-based FTCFs exhibit impressive attributes including a low sheet resistance of 30 ohms per square and a high optical transmittance of 90%, resulting in an exceptional figure of merit (FOM) of 99. Remarkably, the Cu@Au NWs/PET film showed remarkable flexibility, retaining its properties after 10 000 cycles of continuous bending. Stability assessments further affirm the sheet resistance of the Cu@Au NW FTCFs remains nearly unchanged over 75 days at ambient temperature. The strategic integration of a gold nanolayer, serving as a protective coating on the Cu NWs, yields substantial enhancements in both electrical conductivity and overall stability within the Cu NW FTCF architecture. Furthermore, the obtained Cu@Au NW films exhibit rapid heating capabilities, reaching a temperature of 67 °C within 30 seconds at 3.5 V and subsequently returning to room temperature at the same rate. In summary, the introduction of a Au protective layer can effectively enhance the oxidation resistance of Cu NWs, which has great application potential in FTCFs in the field of film heaters. [ABSTRACT FROM AUTHOR]

Monolithic aluminum phosphate (AlPO4) with a macro–mesoporous structure has been successfully prepared via the sol–gel process accompanied by phase separation in the presence of poly(ethylene oxide) (PEO). Gelation of the system has been mediated by propylene oxide (PO), while PEO induces a phase separation. The dried gel is amorphous, whereas the crystalline tridymite phase precipitates upon heating above 1000 °C. Heat treatment does not spoil the macroporous morphology of the AlPO4 monoliths. Nitrogen adsorption–desorption measurements revealed that the skeletons of the dried gels possess a mesostructure with a median pore size of about 30 nm and a surface area as high as 120 m2 g−1. Hydrothermal treatment before heat treatment can increase the surface area to 282 m2 g−1.

Electromagnetic interference (EMI) shielding materials, especially ones with excellent shielding effectiveness (SE), high optical transmittance, long‐term stability as well as high uniformity, are urgently desired to meet the requirements of many applications. Herein, an extremely transparent, stable and uniform silver nanowire (Ag NW)–poly(3,4‐ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) composite film as an EMI shielding material is prepared, which possess excellent shielding capability to both small signal and high power microwaves (HPM). The composite film exhibits SE of 30.5 dB in the frequency range of 1–12 GHz (small signal) and simultaneously has an optical transmittance of 91.0%. The SE continuously increases to 41.4 dB, while the optical transmittance still maintains at 81.1%. The composite film is very uniform, and its SE is almost unchanged even when exposed in air for a year. The SE of this composite film under the excitation of HPM is also thoroughly investigated. The HPM SE is much larger than that of small signal. As the power density of HPM is increased, the SE firstly remains unchanged, then continuously increases, and finally saturates. The SE exceeds 50 dB with the excitation power density of 40 W. More interestingly, the SE is saturated at a fixed HPM power density. [ABSTRACT FROM AUTHOR]