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In this work, we present a systematic study on the solid solution, lattice parameters and superconductivity on the Fe y Te 1−x X x (X = Se, S) system. It has been found that the limit of the Te-site doping with Se and S is around 0.5 and 0.15, respectively. The solid solution with the Fe content changing is also measured in this work, and the single-phase region for preparing pure sample is presented. Based on the magnetic susceptibility measurements, we presented a three-dimensional graph for showing the variation of superconducting critical temperature as a function of both the chalcogen and Fe content in Fe y Te 1−x X x .

Phosphomolybdic acid (H3PMo12O40, POM) was attempted to be used as the energy‐storage agent in this paper to avoid some problems of the direct methanol fuel cell (DMFC), such as catalyst poisoning and methanol permeation. Catalytic oxidation of methanol by aqueous POM on Al2O3 supported catalysts with Pt and Ru active metal was evaluated in the presence of liquid water. The process takes advantage of the high catalytic activities of platinum for methanol oxidation. The effects of temperature, reaction time, and methanol concentration on activity were observed. The catalytic activity of Pt/Al2O3 is better than that of Ru/Al2O3 for the oxidation of methanol by POM. The methanol conversion rate reached 93.55% on the Pt/Al2O3 at 80 °C after reaction for 1 h. The electrochemical experiments indicate that POM shows a larger current density in redox processes on an Au electrode than methanol. The redox process of reduced POM is a reversible multi‐electron transfer process.

This article provides a new kind of P/M processing by designing thin-layered FeS film coated on the surface of iron powder particles for preparing high density Fe-Cu-C materials. Experimental results showed that FeS lubricating coating on the surface of iron powder particles was significant as a means of reducing friction in the pressing process of Fe-Cu-C alloys. After being pressed, the green density increased from 7.18 to 7.42 g cm −3 . The sintered density increased from 7.10 to 7.37 g cm −3 . In the sintering process, the FeS was liquid, and useful in purifying particle surface and strengthening grain boundaries to improve the mechanical properties. The hardness and tensile strength of the Fe-2.0Cu-0.9C-0.5FeS 2 material were 80.5 HRB and 590 MPa. Analysis of fracture showed the main fracture was transgranular fracture. And FeS spherical particles gathered in the pores of the Fe-Cu-C alloys.