In-situ Functionalized Modulation Of Nanoporous Copper-based Alloys And Their Energy Storage Applications

In order to address the problem of the large volume changes and severe hysteresis kinetics for anode materials of secondary battery based on the alloying/conversion mechanism,the integrated nanoporous electrodes were constructed by using nanoporous copper-based alloys as self-sacrificing templates or flexible conductive substrates,supplemented by modulation of interfacial defects in the active materials.Their electrochemical performance,kinetic analysis and charge storage mechanisms were systematically investigated.It is expected to provide a meaningful direction for designing high-performance secondary battery.The detail contents list as follows:（1）The oxygen vacancies activated Mn O/graphene submicron arrays（Ovs-Mn O/G NAs）were self-assembled on annealed nanoporous Cu-Mn alloy by a combination of solid diffusion,chemical vapor deposition and etching process,and their lithium-ion storage behavior and stabilization mechanism were systematically investigated.As a result,the submicron needle offers large number of mesopores for effective lithium-ion diffusion during repeated cycling.Meanwhile,the synergistic effect between graphene coating and activated oxygen vacancies can significantly enhanced lithium-ion kinetic behavior and achieved efficient lithium-ion storage performance.（2）The integrated Cu-decorated Cu-Mn bimetallic oxides with oxygen vacancies were fabricated by phase separation from spontaneous oxidation and hydrogen etching treatment using nanoporous Cu-Mn alloy as self-sacrificial templates,and their sodium-ion storage behavior and stabilization mechanism were systematically investigated.As a result,the inhibition effect of manganese oxide as an‘‘anchor”on grain aggregation of surrounding copper oxides was further confirmed during long-term cycles.Additionally,the expanded lattices and increased oxygen vacancies in cycled Ov-BMO-Cu electrode synergistically guarantee fast charge transfer and effective sodium-ion diffusion,resulting in superior rate capability,long cycle life and practicability.（3）The integrated nanoporous Ni-Cu-Mn ternary metal sulfides with oxygen/sulfur vacancy were fabricated by vulcanization and hydrogen etching based on dealloyed Ni-Cu-Mn alloy,and the effects of electrode morphology and structure on sodium-ion storage performance were further investigated.The results show that the enhanced oxygen/sulfur vacancies in the heterostructures of nanoporous Ni-Cu-Mn ternary metal sulfides can significantly alleviate the volume expansion and promote the rapid charge transfer and diffusion of sodium ions,thereby realizing the desirable electrochemical performances.（4）The aqueous alkaline Ni-Zn batteries were assembled by the nanoporous Ni-Mn oxy-hydroxide cathode and nanoporous Cu-Zn anode based on the chemical dealloyed Ni₃₀Mn₇₀alloy and Cu₃₀Mn₇₀alloy.Benefiting from the integrated electrode structures,the nanoporous Ni-Mn oxy-hydroxide and porous Cu-Zn electrodes present relatively high reversibility of electrochemical reactions.Thus,the np-NMOOH//np-CZ batteries deliver high reversible capacity and outstanding rate capability,exhibiting potential application values.