A recyclable method for titanium extraction and oxygen evolution from Ti-bearing slags

Despite its existence for more than 80 years,the titanium industry is still challenged by massive carbon emissions,high production costs,and large resource waste.More than one hundred million tons of Ti-bearing blast furnace slag(TB-slag)has been discarded in China because of the difficulty of reutilization,which requires efficient titanium extraction and recovery technologies.This paper describes a low-cost,carbon-emission-free method for Ti extraction and oxygen evolution via molten oxide electrolysis(MOE)vacuum distillation.After a comprehensive analysis of the binding energies and activities of liquid metals,the highlights of our study are as follows.1)Sb has the best preferential deposition of Ti among a series of high-Ti-affinitive liquid metal cathodes(Cu,Ni,Pb,Sn,and Sb).2)The Ir anode was first used in TB-slag with IrO_(2) formed on its surface to protect it from further corrosion.3)An alloy containing Ti and Ca can be obtained by MOE,and Ti and Ca metals can be refined by further vacuum distillation.4)A closed loop is formed in the overall process owing to the recyclable Sb cathode and continuous feeding of TB-slag into the electrolyte.This simple,low-cost,and environmentally friendly method can realize the efficient utilization of Ti resources and achieve carbon neutrality.

Single-atom electrocatalyst and gel polymer electrolyte boost the energy density and life of aluminum-sulfur batteries

Aluminum-sulfur(Al-S)batteries are regarded as a desirable candidate for large-scale energy storage be-cause of their high energy density and abundant natural resources of electrode materials.To address the critical issues of low discharge voltage and rapid capacity decay in Al-S batteries,here an electrocatalyst-assisted gel-polymer electrolyte(GPE)-based Al-S battery is fabricated using platinum nanoparticles deco-rated platinum/nitrogen co-doped graphene(PtNG)as sulfur host for positive electrode and metal-organic frameworks(MOF)filled GPE(MOF@GPE)as solid electrolyte.Pt-based active sites derived from Pt nan-oclusters’surface and atomically dispersed Pt-N_(2) chemical bonds in PtNG can catalyze the decomposition of sulfur and polysulfides in the electrochemical process,greatly accelerating the sulfur redox kinetics.Furthermore,the MOF fillers in MOF@GPE electrolyte significantly inhibit the shuttle effect of polysul-fides,efficiently improving the utilization of sulfur.Consequently,the established Al-S battery delivers a specific capacity of 1009 mAh g^(−1) with a discharge plateau of∼0.95 V,along with a capacity retention of 65% after 300 cycles,revealing ultrahigh energy density and long cycle life.Such a strategy of combin-ing electrocatalyst and MOF-based gel electrolyte affords a fresh plateau for promoting the rechargeable ability of Al-S batteries,advancing remarkable routes for achieving efficient and stable energy storage devices.