The 93 W and Mo1 refractory metals were bonded with different Cu_(1-x)Ni_(x) coating interlayers of various Ni content using plasma-activated sintering at 700℃.The effects of the Ni content in the Cu_(1-x)Ni_(x) coat...The 93 W and Mo1 refractory metals were bonded with different Cu_(1-x)Ni_(x) coating interlayers of various Ni content using plasma-activated sintering at 700℃.The effects of the Ni content in the Cu_(1-x)Ni_(x) coating interlayer on the interfacial microstructure evolution and mechanical properties of the W/Mo joints were studied.The maximum average shear strength of the W/Mo joint was 316.5 MPa when the Ni content of the Cu_(1-x)Ni_(x) coating interlayer was 25%.When the Ni content of the Cu_(1-x)Ni_(x) coating interlayer was below 50%,the atomic diffusion at the W/Mo joint interface was adequate without the formation of intermetallic compounds,as demonstrated by the High Resolution Transmission Electron Microscope analyses of the joints.The presence of Ni in Cu_(1-x)Ni_(x) promoted diffusion bonding at the interface,which contributed to the high mechanical properties of the W/Mo joint.With an increase in the Ni content of the Cu_(1-x)Ni_(x) coating interlayer,the Mo Ni intermetallic compound(IMC)nucleated and grew at the Cu1-xNix coating/Mo1 interface.When the Ni content of the Cu_(1-x)Ni_(x) coating interlayer was above 50%,the generation of a brittle Mo Ni IMC weakened the shear strength of the W/Mo joint dramatically.展开更多
Solar photocatalysis,as a method of green energy production and sustainable technology,has been regarded as one of the most effective strategies to resolve environmental issues and the current energy crisis.In this wo...Solar photocatalysis,as a method of green energy production and sustainable technology,has been regarded as one of the most effective strategies to resolve environmental issues and the current energy crisis.In this work,intimate contact hollow Ni_(x)Co_(1-x)S polyhedron/g-C3N4 nanosheet composites were prepared in-situ through a facile one-step hydrothermal method.The as-prepared Ni_(x)Co_(1-x)S/g-C_(3)N_(4) composites showed superior photocatalytic activity and high stability for H2 generation and methyl orange(MO)degradation under visible light irradiation.The optimized 4 wt.%Ni_(x)Co_(1-x)S/g-C_(3)N_(4) composite attained a maximum H2 evolution rate of 1420μmol g^–1 h^–1,which was about 157 times higher than that of pure g-C3N4.In addition,the Ni_(x)Co_(1-x)S/g-C_(3)N_(4) composite also exhibited greatly improved photocatalytic activity for dye degradation,which for MO was at 98.14%in 9 min.The outstanding photocatalytic performance was predominantly attributed to the unique architecture of hollow Ni_(x)Co_(1-x)S polyhedrons,which not only provided more active sites at the edges and surface as convenient charge transfer channels,but also promoted the separation and transport of electron-hole pairs.This work provides some novel ideas for the design and development of highly efficient noble metal-free cocatalyst/semiconductor systems for photocatalytic H2 generation and dye degradation.展开更多
基金the National Natural Science Foundation of China(Nos.51572208 and 51521001)the 111 Project(No.B13035)the Joint Fund(No.6141A02022255)。
文摘The 93 W and Mo1 refractory metals were bonded with different Cu_(1-x)Ni_(x) coating interlayers of various Ni content using plasma-activated sintering at 700℃.The effects of the Ni content in the Cu_(1-x)Ni_(x) coating interlayer on the interfacial microstructure evolution and mechanical properties of the W/Mo joints were studied.The maximum average shear strength of the W/Mo joint was 316.5 MPa when the Ni content of the Cu_(1-x)Ni_(x) coating interlayer was 25%.When the Ni content of the Cu_(1-x)Ni_(x) coating interlayer was below 50%,the atomic diffusion at the W/Mo joint interface was adequate without the formation of intermetallic compounds,as demonstrated by the High Resolution Transmission Electron Microscope analyses of the joints.The presence of Ni in Cu_(1-x)Ni_(x) promoted diffusion bonding at the interface,which contributed to the high mechanical properties of the W/Mo joint.With an increase in the Ni content of the Cu_(1-x)Ni_(x) coating interlayer,the Mo Ni intermetallic compound(IMC)nucleated and grew at the Cu1-xNix coating/Mo1 interface.When the Ni content of the Cu_(1-x)Ni_(x) coating interlayer was above 50%,the generation of a brittle Mo Ni IMC weakened the shear strength of the W/Mo joint dramatically.
基金financially supported by the National Natural Science Foundation of China(No.21801091)the Science Technology Development Planning of Jilin Province(No.20190103117JH)the Education Department Project of Jilin Province(Nos.JJKH20200242KJ and JJKH20190827KJ)。
文摘Solar photocatalysis,as a method of green energy production and sustainable technology,has been regarded as one of the most effective strategies to resolve environmental issues and the current energy crisis.In this work,intimate contact hollow Ni_(x)Co_(1-x)S polyhedron/g-C3N4 nanosheet composites were prepared in-situ through a facile one-step hydrothermal method.The as-prepared Ni_(x)Co_(1-x)S/g-C_(3)N_(4) composites showed superior photocatalytic activity and high stability for H2 generation and methyl orange(MO)degradation under visible light irradiation.The optimized 4 wt.%Ni_(x)Co_(1-x)S/g-C_(3)N_(4) composite attained a maximum H2 evolution rate of 1420μmol g^–1 h^–1,which was about 157 times higher than that of pure g-C3N4.In addition,the Ni_(x)Co_(1-x)S/g-C_(3)N_(4) composite also exhibited greatly improved photocatalytic activity for dye degradation,which for MO was at 98.14%in 9 min.The outstanding photocatalytic performance was predominantly attributed to the unique architecture of hollow Ni_(x)Co_(1-x)S polyhedrons,which not only provided more active sites at the edges and surface as convenient charge transfer channels,but also promoted the separation and transport of electron-hole pairs.This work provides some novel ideas for the design and development of highly efficient noble metal-free cocatalyst/semiconductor systems for photocatalytic H2 generation and dye degradation.
