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To improve photoelectrochemical properties of Si nanowires (SiNWs), MoS2/SiNWs is prepared via two-step method. SiNWs is synthesized by metal−catalyzed electroless etching (MCEE) method and MoS2 is subsequently deposited onto SiNWs through the direct thermal decomposition method. MoS2 is introduced as both light absorber and catalyst for hydrogen evolution reaction (HER). Moreover, it forms a heterojunction with SiNWs that contribute to the charge separation. Herein, MoS2/SiNWs attains excellent hydrogen evolution reaction (HER) catalysis with onset potential of 55 mV. A photocurrent density of 25 mA cm− 2 at −1.0 VRHE were achieved under simulated solar illumination, which is about 6 times higher than that of SiNWs, and the carrier concentration is increased by 100−fold. The enhanced photocatalytic activity of MoS2/SiNWs toward HER is attributed to the Schottky junction at the interface, which enhances the photo−generation of electron−hole pairs and suppresses the charge recombination, making them promising earth−abundant alternatives to noble metal−based photocathode for HER. [ABSTRACT FROM AUTHOR]

A brief analysis of the characteristic of the compound planetary gear technology is carried out,and the performance and the values of the mean load factor of the compound planetary are discussed. The calculation method of the maximum phase difference of the meshing points and the calculation method of mean load share performance for turning angle are put forward. In a compound planetary,there is a certain amount of floating in the inner gear ring,except for the float of the sun,the connecting segments of the twin planetary shaft,inner gear ring and the spindle produce certain torsional deformations. Through numerical examples illustrate that the torsional deformations of the sun and inner gear are more than simple planetary,the compensation manufacturing deviation caused by the uneven load ability is stronger,so there will be a lower mean load factor.According to theoretical analysis and test data which has been obtained and the successful application of actual design,it is appropriate to take 1. 10 as the planetary mean load factor of the compound planetary of four planets in the design of wind power gear.