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The materials combining high-entropy alloys with good mechanical properties and magnetic materials with a significant magnetocaloric effect are among the best candidates for magnetic refrigeration. For this purpose, the high-entropy alloys (MnNiSi) 1- x (FeCoGe) x (x = 0.4, 0.42, 0.45, and 0.47) were designed in this study. The effects of the Si/Ge ratio on the magnetocaloric effect and mechanical properties were also investigated. The results show that high-entropy alloy (MnNi) 0.6 Si 0.62 (FeCo) 0.4 Ge 0.38 possesses a Vickers hardness value of 580.6HV2 and compressive strength of 267 MPa with respect to a significant entropy change of 48.5 J·kg−1K−1 under a magnetic field of 5 T near the Curie temperature of 308.8 K. In order to clearly understand the origin of this excellent comprehensive performance, the influence mechanism of crystal structure and configurational entropy were explored. Furthermore, the first-principles calculations indicated that the magnetic properties mainly originate from Mn atoms located in 3 d sites and are influenced by the interaction between the Mn and Fe atoms. Additionally, the total magnetic moment and electron density are taken into account to reveal their influence on magnetocaloric properties. [Display omitted] • An MnNiSi-based magnetocaloric high-entropy alloys with excellent comprehensive properties were obtained. • The MnNiSi-based alloys have good mechanical properties (the Vickers hardness of 580.6 HV2 and compressive strength of 267 MPa). • The magnetocaloric effects of the MnNiSi-based alloys is 48.5 J·kg−1K−1 under 0–5 T at T C = 309 K. • The physical mechanism about good mechanical properties and magnetocaloric effects is revealed from the crystal structure, configurational entropy and electronic structure. [ABSTRACT FROM AUTHOR]

• Flower-ball shaped Ag/Bi 2 WO 6 material was synthesized by hydrothermal method. • The gas sensing performance of Ag/Bi 2 WO 6 for ethanol was investigated for the first time. • Ag/Bi 2 WO 6 -based gas sensor has a fast response speed of up to 7 s for ethanol. • The sensor based on Ag/Bi 2 WO 6 showed low operating temperature of 240℃ to ethanol. Although Bi 2 WO 6 has been applied in various field, there are few reports on the application of gas sensing. In this work, Ag loaded flower-ball shaped Bi 2 WO 6 composite nanomaterials were synthesised by hydrothermal method. The Ag content was optimized for the first time. It was found that when 2 % Ag was added, Ag/Bi 2 WO 6 material possessed high sensitivity and low optimal working temperature (240℃). Compared with pure Bi 2 WO 6 (11 s and 32 s), Ag/Bi 2 WO 6 possessed ultrashort response and recovery time of 7 s and 25 s. It exhibited better ethanol gas selectivity and stability. Unique crystal structure and Ag catalysis may lead to the improvement of gas sensing performance. [ABSTRACT FROM AUTHOR]