The self-assembling growth of copper nanowires for transparent electrodes

Long (15 - 40 μm), thin (diameter of 20 ± 5 nm), and well-dispersed CuNWs Cu nanowires were prepared. The high-resolution TEM and selected area electron diffraction showed that the CuNWs were single-crystalline. To investigate the growth mechanism, we examined the microstructure of these CuNWs at different reaction time. It was found that the CuNWs were actually formed through the self-assembling of Cu nanoparticles along the [110] direction. The transparent electrodes fabricated using the CuNWs achieved a high transparency of 76 % at 31±5 Ω/□

High performance perovskite sub-module with sputtered SnO2 electron transport layer

Hybrid perovskite solar cells (PSC) have gained stupendous achievement in single/tandem solar cell, semitransparent solar cell and flexible devices. Aiming for potential commercialization of perovskite photovoltaic technology, up scalable processing is crucial for all function layers in PSC. Herein we present a study on room temperature magnetron sputtering of tin oxide electron transporting layer (ETL) and apply it in a large area PSC for low cost and continues manufacturing. The SnO2 sputtering targets with varied oxygen and deposition models are used. Specifically, the working gas ratio of Ar/O2 during the radio frequency sputtering process plays a crucial role to obtain optimized SnO2 film. The sputtered SnO2 films demonstrate similar morphological and crystalline properties, but significant varied defect states and carrier transportation roles in the PSC devices. With further modification of thickness of SnO2, the PSCs based on sputtered SnO2 ETL shows a champion efficiency of 18.20% in small area and an efficiency of 14.71% in sub-module with an aperture area of 16.07 cm2, which is the highest efficiency of perovskite sub module with sputtered ETLs

Lead halide–templated crystallization of methylamine-free perovskite for efficient photovoltaic modules

Upscaling efficient and stable perovskite layers is one of the most challenging issues in the commercialization of perovskite solar cells. Here, a lead halide–templated crystallization strategy is developed for printing formamidinium (FA)–cesium (Cs) lead triiodide perovskite films. High-quality large-area films are achieved through controlled nucleation and growth of a lead halide•N-methyl-2-pyrrolidone adduct that can react in situ with embedded FAI/CsI to directly form α-phase perovskite, sidestepping the phase transformation from δ-phase. A nonencapsulated device with 23% efficiency and excellent long-term thermal stability (at 85°C) in ambient air (~80% efficiency retention after 500 hours) is achieved with further addition of potassium hexafluorophosphate. The slot die–printed minimodules achieve champion efficiencies of 20.42% (certified efficiency 19.3%) and 19.54% with an active area of 17.1 and 65.0 square centimeters, respectively

Preparation and thermophysical properties of graphite flake-carbon fiber coreinforced copper matrix composites

Graphite flake-carbon fiber coreinforced copper matrix composites were prepared by vacuum hot pressing technology. The carbon fibers were dispersed ultrasonic in alcohol and then mixed with graphite flake and alloys powder (Zr and Cu) for hot pressing sintering. The effects of the carbon fiber content on the microstructure, bending strength and thermal conductivity of the composites were investigated. The results show that the interface of the composites is well bonded. When the volume fraction of carbon fiber is 1%–3%, the carbon fiber can be uniformly dispersed in the matrix, and the bending strength of the composites can be improved effectively. When the volume fraction of carbon fiber is 2%, the bending strength reaches a maximum of 152 MPa, which is an increase of 60% compared with that of the composites without carbon fiber. However, an excessive addition of carbon fiber (4% or more) leads to an uneven distribution of carbon fiber, and the bending strength of the composites decreases. When the volume fraction of carbon fiber is 2%, the thermal conductivity of the composite is 597 W·m ^−1 ·K ^−1 . The acoustic mismatch model (AMM) associated with the Digimat MF module is able to predict the thermal conductivity of the anisotropic multiphase composites

SnSe Monolayer-Based heavy metal sensors with high Sensitivity, Selectivity, and Reusability: Insights from first principle calculation

Heavy metal pollution has a negative impact on both human health and the environment. The monitoring of heavy metal is therefore very important from a practical standpoint. In this study, the adsorption energy, charge transfer, band, densities of states, and sensitivity of SnSe monolayers toward heavy metals (As, Cd, Cr, Hg, Ni, Pb) were investigated using density functional theory combined with the non-equilibrium Green's function approach. The calculations show that SnSe monolayers have excellent sensitivities exceeding the limit of quantitation (LOQ) towards As, Cd, Hg, and Pb, which are as high as 384467%, 1462%, 1791%, and 26160%, respectively. Moreover, analyzing response peaks at various bias voltages can identify the composition of heavy metals from diverse sources, providing valuable insights for selective heavy metal monitoring. SnSe monolayers exhibit wide bias voltage windows that enhance sensor sensitivity by reaching the detection threshold, while also simplifying sensor encapsulation, resulting in higher reliability. The SnSe monolayer exhibits rapid recovery times for As, Hg, and Cd at room temperature, while for Pb, heating to 498 K is required for rapid recovery. These findings show that SnSe monolayers have a strong potential for constructing extremely sensitive and selective heavy metal sensors that are also reusable, implying that SnSe monolayers might serve as a possible online sensor for environmental monitoring

A Pedagogical Approach to Incorporating the Concept of Sustainability into Design-to-Physical-Construction Teaching in Introductory Architectural Design Courses: A Case Study on a Bamboo Construction Project

Sustainable architectural education is offered in colleges and universities all over the world. Studies have emphasized the importance of sustainable architectural education in introductory courses of architecture major programs, but methods and strategies for teaching sustainable architecture at lower levels are scarce. This study focuses on the design-to-physical-construction process and creates a teaching framework that incorporates the concept of sustainable development from the perspectives of sustainable economy, environment and society. Based on the teaching method of learning through the design-to-physical-construction process and referring to the grounded theory, a case study on a bamboo construction project was conducted to explore approaches and strategies of sustainable architectural education in introductory courses. Results reveal that five systems, including the system of sustainable development, consist of a framework that illustrated the teaching effects. Based on the framework, we discovered five factors that should be considered in incorporating the concept of sustainable development into architectural design teaching, including the necessity of conducting sustainable architectural education in introductory courses. This study helps explore the potential role sustainability plays in incorporating interdisciplinary knowledge, connecting specialized knowledge across different program levels, and motivating student learning. It also provides a reference for the practice of sustainable architectural education

Silver ants-inspired flexible photonic architectures with improved transparency and heat radiation for photovoltaic devices

Silver ants-inspired flexible photonic architectures with improved transparency and heat radiation for photovoltaic device

Robust transparent superamphiphobic coatings on non-fabric flat substrates with inorganic adhesive titania bonded silica

The technological implementation of superamphiphobic surfaces has been largely hindered by the stability issues caused by surface abrasion, corrosion, contamination, etc. Robustness still remains the major challenge for a well-performing superamphiphobic coating. In this study, the simple route of spraying inks containing pre-designed silica, cetyltrimethylammonium bromide (CTAB) and titanium diisopropoxide bis-2,4-pentanedionate (TAA) is presented to prepare micro–nanostructure films. The mechanical properties of the films are significantly strengthened by titania after the pyrogenic decomposition of TAA, and the films are able to withstand a standard 2H pencil scratching and sand flow impact. The as-made films exhibit excellent super-repellency to various liquids after treatment with 1H,1H,2H,2H-perfluorodecyltrichlorosilane (PFTS). The static contact angles (SCAs) for water (surface tension 72.1 mN m−1) and dodecane (surface tension 25.3 mN m−1) can reach 166° ± 3° and 153° ± 3°, respectively. On controlling the thickness of the films, the optical transmittance of the films (400 nm thick) can come close to that of glass. Moreover, efficient photocatalytic decomposition of an organic substance attached on the surfaces is demonstrated; this decomposition enables the recovery of the superamphiphobic property of the contaminated films. Thus, the unique properties of robustness, transparency and self-healing, etc., combined with the relatively low cost fabrication, make these superamphiphobic coatings promising in various applications

Ultrasonic Spray-Coating of Large-Scale TiO2 Compact Layer for Efficient Flexible Perovskite Solar Cells

Flexible electronics have attracted great interest in applications for the wearable devices. Flexible solar cells can be integrated into the flexible electronics as the power source for the wearable devices. In this work, an ultrasonic spray-coating method was employed to deposit TiO2 nanoparticles on polymer substrates for the fabrication of flexible perovskite solar cells (PSCs). Pre-synthesized TiO2 nanoparticles were first dispersed in ethanol to prepare the precursor solutions with different concentrations (0.5 mg/mL, 1.0 mg/mL, 2.0 mg/mL) and then sprayed onto the conductive substrates to produce compact TiO2 films with different thicknesses (from 30 nm to 150 nm). The effect of the different drying processes on the quality of the compact TiO2 film was studied. In order to further improve the film quality, titanium diisopropoxide bis(acetylacetonate) (TAA) was added into the TiO2-ethanol solution at a mole ratio of 1.0 mol % with respect to the TiO2 content. The final prepared PSC devices showed a power conversion efficiency (PCE) of 14.32% based on the indium doped tin oxide coated glass (ITO-glass) substrate and 10.87% on the indium doped tin oxide coated polyethylene naphthalate (ITO-PEN) flexible substrate

Universal passivation strategy to slot-die printed SnO₂ for hysteresis-free efficient flexible perovskite solar module

Perovskite solar cells (PSCs) have reached an impressive efficiency over 23%. One of its promising characteristics is the low-cost solution printability, especially for flexible solar cells. However, printing large area uniform electron transport layers on rough and soft plastic substrates without hysteresis is still a great challenge. Herein, we demonstrate slot-die printed high quality tin oxide films for high efficiency flexible PSCs. The inherent hysteresis induced by the tin oxide layer is suppressed using a universal potassium interfacial passivation strategy regardless of fabricating methods. Results show that the potassium cations, not the anions, facilitate the growth of perovskite grains, passivate the interface, and contribute to the enhanced efficiency and stability. The small size flexible PSCs achieve a high efficiency of 17.18% and large size (5 × 6 cm2) flexible modules obtain an efficiency over 15%. This passivation strategy has shown great promise for pursuing high performance large area flexible PSCs