CAJ | 학술논문

研究了Mn替代Ni对La_2Mg_(0.9)Al_(0.1)Ni_(7.5-x)Co_(1.5)Mn)_x (x=0, 0.3, 0.6, 0.9)贮氢合金相结构和电化学性能的影响.XRD Rietveld全谱拟合分析表明:Mn替代改变了合金的物相组成和物相的丰度.LaNi_3相消失,αLa_2Ni_7相丰度的变化表现为先增加(x=0,0.3)后减少(x=0.6,0.9),LaMgNi_4相和La_5Ni_(19)相的丰度则随合金中Mn含量x的增加而增加.Mn替代Ni降低了合金的贮氢容量、最大电化学放电容量和活化性能,La_2Mg_(0.9)Al_(0.1)Ni_(7.2)Co_(1.5)Mn_(0.3) 合金电极表现出最好的电化学循环稳定性,合金的高倍率放电性能随Mn含量的增加降低,这归因于交换电流密度(I_0)和氢扩散系数(D)的降低.
연구료Mn체대Ni대La_2Mg_(0.9)Al_(0.1)Ni_(7.5-x)Co_(1.5)Mn)_x (x=0, 0.3, 0.6, 0.9)저경합금상결구화전화학성능적영향.XRD Rietveld전보의합분석표명:Mn체대개변료합금적물상조성화물상적봉도.LaNi_3상소실,αLa_2Ni_7상봉도적변화표현위선증가(x=0,0.3)후감소(x=0.6,0.9),LaMgNi_4상화La_5Ni_(19)상적봉도칙수합금중Mn함량x적증가이증가.Mn체대Ni강저료합금적저경용량、최대전화학방전용량화활화성능,La_2Mg_(0.9)Al_(0.1)Ni_(7.2)Co_(1.5)Mn_(0.3) 합금전겁표현출최호적전화학순배은정성,합금적고배솔방전성능수Mn함량적증가강저,저귀인우교환전류밀도(I_0)화경확산계수(D)적강저.
Effect of Mn substitution for Ni on phase constitution and electrochemical characteristics of La_2Mg_(0.9)Al_(0.1)Ni_(7.5-x)Co_(1.5)Mn_x (x=0, 0.3, 0.6, 0.9) hydrogen storage alloys was studied. It is found that Mn substitution will change phase composition and phase constitution of the alloys. LaNi_3 phase disappears; the components of αLa_2Ni_7 first increases with Mn content from x=0 to x=0.3 and then decreases from x=0.6 to 0.9. Both component of LaMgNi_4 phase and La_5Ni_(19) phase increase as x increases in the alloys. Replacement of Ni by Mn will lower hydrogen storage capacity, maximum electrochemical discharge capacity and activation property of the alloy electrodes. La_2Mg_(0.9)Al_(0.1)Ni_(7.2)Co_(1.5)Mn_(0.3) hydride electrode shows the best cycle stability. The high rate dischargeability of the alloys decreases with the increase of Mn content, which would be attributed to the decrease of exchange current density (I_0) and diffusion coefficient of the hydrogen atom (D).