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Due to the high conductivity and stability of silver, silver ink has been widely used in the field of printed electronics. However, since mechanical strain would cause the contact between key particles to be broken. Recently, higher requirements have been put on the bending resistance of silver paste. In this experiment, by preparing Ag NPs: Ag Flakes composite materials of 20:80 and 30:70 respectively, a new method for preparing stable modified flake silver powder is proposed, and the attachment and growth methods of Ag NPs reduced on micron flake silver powder is discussed. Flake silver powder, dispersant and reducing agent are added to the silver-ammonia complex, and the nano-silver particles are reduced on the flake silver powder by controlling the reaction conditions. When Ag+: Ag Flakes in the solution is 30:70, there is a clear interface between the silver particles and the silver flakes, and the size distribution range is between 10 and 100 nm; when Ag+: Ag Flakes is 20:80, the distance between the nano-silver particles and the silver plate crystal plane is about 0.222 nm and 0.260 nm, these spacings represent the (1–12) and (004) planes of Ag, respectively. The reduced silver particles grow on the surface of the silver sheet, the size is about 5 ∼ 60 nm, and form a sheet-point combination of shaped silver powder, which can be used to make conductive silver paste with cost and performance competitiveness. The reaction can be completed at room temperature (5 ∼ 25 °C) and atmospheric pressure (80 ∼ 100 kPa), the operation is simple, the reaction time is short, and it has a positive effect on the commercial production of printable highly conductive silver paste.

Flexible all-solid-state supercapacitors (ASSSs) have caught the scientific attention to meet the explosive demand for portable and wearable electronic devices. However, it is difficult for flexible electrode materials to obtain a high areal capacitance at a high mass loading, which limits their commercial applications. In this study, vanadium oxide (V2O5) nanoparticles are introduced into Ti3C2 flakes with the aid of cetyltrimethylammonium bromide (CTAB). The intercalation of V2O5 particles in the interlayer of Ti3C2 establishes a hierarchical structure and facilitates the electrolyte penetration. As a result, the prepared CT-Ti3C2@V2O5 composite electrode achieves a high areal capacitance of 2065 mF cm-2 at 3 mA cm-2 and superior active mass loading (15 mg cm-2). Meanwhile, over 93% capacitance is maintained after 6000 cycles at 18 mA cm-2. The ASSS based on CT-Ti3C2@V2O5 delivers a high areal capacitance of 477 mF cm-2 at 1 mV s-1 and exhibits stable performance at different bending states, which reaches to the advanced level for the ASSSs based on MXenes.

Based on the statistic theory and image processing technology, a three-dimensional reconstructed model of pore structure for sandstone is established. On the basis of the model, the numerical simulation experiment is carried out to analyze the influence of pore structure parameters (pore size, shape and porosity) on the deformation, stress distribution and failure distribution of sandstone under the splitting load. The research results show that the effect of void morphology on the damage of sandstone is obvious. With the change of the pore shape from the ellipsoid to the sphere, the fracture zone of the splitting disc is increased and more dispersed. With the pore shape is changed from sphere to ellipsoid, the maximum stress along the Y direction is firstly decreased and then increased. When the pore size increases, the failure mode becomes a single tensile failure from an induced-tension-shear failure, and the maximum stress along the Y direction is decreased. But the influence degree is weakened with the increase of the pore size of the model. Along with the increase of the porosity, the maximum stress along the Y direction is increased, therefore, the sandstone is easy to damage. But the degree of influence decreases with the increase of pore size. The results reveal the influence of the parameters of the pore structure on the mechanical properties of rock, which provide some reference for the study of the effect of pore structure on the rock physical mechanical properties.

A green and facile process was developed to fabricate ultrafine p-type Cu2O single crystal nanowires by anodizing copper (Cu0) particles preloaded on TiO2?nanotube arrays. The Cu2O nanowires with a diameter of less than 5?nm were assembled on the top surface of n-type TiO2?nanotube arrays, constructing a novel p?n junction heterostructure with larger specific surface area compared to the unmodified TiO2?nanotube arrays. X-ray diffractometer (XRD) and high-resolution transmission electron microscopy (HRTEM) were employed to demonstrate that the resulting Cu2O was single crystalline. The composite Cu2O/TiO2?nanotube arrays exhibited significantly enhanced response to the visible light, resulting from Cu2O with a narrow-band gap. Furthermore, under visible light irradiation, enhanced efficiency in separating photogenerated hole?electron pairs was achieved due to the potential difference generated on the p?n interface. A possible mechanism was proposed to explain the formation of crystal Cu2O nanowires.