Strong coordination interaction in amorphous Sn-Ti-ethylene glycol compound for stable Li-ion storage

Sn has been considered one of the most promising metallic anode materials for lithium-ion batteries(LIBs)because of its high specific capacity.Herein,we report a novel amorphous tin-titanium-ethylene glycol(Sn-Ti-EG)bimetal organic compound as an anode for LIBs.The Sn-Ti-EG electrode exhibits exceptional cyclic stability with high Li-ion storage capacity.Even after 700 cycles at a current density of 1.0 A g−1,the anode maintains a capacity of 345 mAh g−1.The unique bimetal organic structure of the Sn-Ti-EG anode and the strong coordination interaction between Sn/Ti and O within the framework effectively suppress the aggrega-tion of Sn atoms,eliminating the usual pulverization of bulk Sn through volume expansion.Furthermore,the Sn M-edge of the X-ray absorption near-edge structure spectra obtained using soft X-ray absorption spec-troscopy signifies the conversion of Sn2+ions into Sn0 during the initial lithiation process,which is reversible upon delithiation.These findings reveal that Sn is one of the most active components that account for the excellent electrochemical performance of the Sn-Ti-EG electrode,whereas Ti has no practical contribution to the capacity of the electrode.The reversible formation of organic functional groups on the solid electrolyte interphase is also partly responsible for its cyclic stability.

HCWCI/Carbon Steel Bimetal Liner by Liquid-Liquid Compound Lost Foam Casting

Impact, friction and corrosion from the grinding balls and the grinding medium during the mineral processing result in liner breakage. Liner, made from Hadfield steel or alloyed steel, could not have served in wet grinding environment for more than ten months. Composite liner, made from HCWCI (high Cr white cast iron) and carbon steel, has been developed successfully with liquid-liquid composing process based on LFC (lost foam casting). The microstructure of composite was analyzed with optical microscope, SEM (scanning electron microscope)/EDX energy-dispersive X-ray and XRD (X-ray diffraction). According to micrograph, the combination region of two metals was staggered like dogtooth, no mixtures occurred between two liquid metals, and its interface presented excellent metallurgical bonding state. The results of mechanical property test show that, the hardness of HRC, the fracture toughness, and the bending strength are more than 61, 16.5 J/cm2 and 1 600 MPa, respectively. Comparison between liners made from bimetal composite and alloyed steel has also been investigated in industrial hematite ball mill. The results of eight months test in wet grinding environment prove that the service life of bimetal composite liner is three times as long as that of one made from alloyed steel.