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In the present work, we reported the fabrication of CdS decorated mesoporous SiC hollow nanofibers for efficient visible-light-driven photocatalytic hydrogen production. The mesoporous SiC hollow nanofibers were firstly fabricated by electrospinning, followed by hydrothermal treatment to introduce the CdS nanoparticles decorated on the preformed fiber matrix, The resultant CdS/SiC hybrid photocatalysts were systematically characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), high-resolution transmission electron microscopy (HRTEM) and N2 adsorption. The as-fabricated CdS/SiC hybrids exhibited a robust stability with a release rate up to ~ 124.65 µmol h−1 g−1 for photocatalytic H2 evolution driven by visible light, which was profoundly enhanced for more than 16 times to that of pristine SiC counterparts, and comparable to the state-of-the-art one of SiC-based photocatalysts.

In the present work, we reported the fabrication of Fe-doped WO3 nanofibers via a versatile electrospinning method towards efficient photoelectrochemical (PEC) water splitting. The resultant Fe-WO3 nanofibers had a high purity in morphology, and the Fe doping levels within the WO3 nanofibers were controlled in the range from 0.32 to 1.47 at.%, making the band gaps of WO3 nanofibers tailored from 2.92 to 2.8 eV. The incorporated Fe dopants could not only increase the light absorption, but also improve the charge transport and charge transfer efficiencies, bringing an enhanced PEC activity of the WO3 nanofiber photoanodes. The WO3 nanofibers with the optimized 0.32 at.% Fe doping level exhibit the best PEC performance. The mechanism for the enhanced PEC behaviors was proposed.

In this work, the failure behavior of a commercial chip size packaging (CSP) with flip chip solder joint was investigated under the coupling condition of thermal cycling and electrical current. The damage behavior of solder joint was real-time monitored through the electrical resistance response. The microstructure evolution under the coupling condition were observed. The failure was classified as three modes, i.e., the cracking within solder on the PCB side (mode I), the cracking along the solder/IMC interface (mode II) and the detachment between the solder and chip due to the complete dissolving of Cu UBM layer (mode III). At low current density the mode I accounted for a large percentage while the mode II and mode III accounted for a large percentage at high current density. Based on the Weibull distribution of failure life, it was found that the mean time to failure sharply decreased with the increasing current density. A lifetime prediction model was constructed for the reliability test under coupling condition of thermal cycling and electrical current.

Fe-doped TiO2 nanofibers with a thoroughly mesoporous structure were prepared via a facile foaming-assisted electrospinning method. The foaming agents and FeAcAc were introduced in the raw materials to create the mesopores and incorporate the Fe dopants into the conventional solid TiO2 nanofibers, respectively, which could be accomplished simultaneously over a one-step calcination process. The photocatalytic experimental results demonstrate that the mesoporous Fe-doped TiO2 nanofibers exhibit significantly enhanced activity toward the RhB degradation and splitting water for hydrogen generation under visible-light illumination, as compared to those of Fe-doped solid and intrinsic thoroughly mesoporous counterparts. The photocatalytic mechanism is proposed that the one-dimensional mesoporous nanostructure can enhance the transportation of the reactant and products, and the Fe-doping induces the shift of the absorption edge into the visible-light range and restrains the recombination of photo-generated electrons and holes, which can synergistically improve their activity.

Improving the photocatalytic efficiency of TiO2 semiconductor is crucially important and highly desired for its practical applications. In the present work, aiming to broaden the photoresponse window and limit the photocatalyst aggregation, we reported the exploration of N-doped TiO2 thoroughly mesoporous nanofibers with high purity in morphology via a foaming-assisted electrospinning strategy. The foaming agents and urea were introduced in the raw materials to create the mesopores and incorporate the N dopants into the conventional solid TiO2 nanofibers, respectively, which could be accomplished simultaneously over one-step calcination process. The synergetic combination of N dopants and one-dimensional mesoporous nanostructure allow the TiO2 fibers to exhibit significantly enhanced visible-light photocatalytic activity toward the Rhodamine B and hydrogen evolution, as compared to those of N-doped solid and intrinsic thoroughly mesoporous counterparts, suggesting their promising applications in water purification and energy supply.

In this study, beard-like and sea cucumber-like silica structures have been successfully synthesized on the Si substrate by a novel and simple water assisted method. The investigation of SEM and TEM reveals that the as-grown products possess many similar features like that they all have a very big, nearly spherical microsized body and uncountable, high density and highly oriented silica nanowire antennas. It is proved that ultrafine nanosized metal catalysts could be generated on the surface of one microsized catalyst during their growth process due to the indications of surface local softening and different elastic deformation along different crystal plane taking place on the catalyst surface during growth process. Our results could introduce a new way to control the growth of high-density and well-oriented functional nanowire arrays with desired morphologies.