The development of an energy storage system with abundant elements is a key challenge for a sustainable society,and the interest of Na intercalation chemistry is extending throughout the research community.Herein,the ...The development of an energy storage system with abundant elements is a key challenge for a sustainable society,and the interest of Na intercalation chemistry is extending throughout the research community.Herein,the impact of Ti integration into NaMnO2 in a binary system of x NaMnO2–(1–x)TiO2(0:5≤x≤1)is systematically examined for rechargeable Na battery applications.Stoichiometric NaMnO2,which is classified as an in-plane distorted O′3-type layered structure,delivers a large initial discharge capacity of approximately 200 mAhg-1,but insufficient capacity retention is observed,most probably associated with dissolution of Mn ions on electrochemical cycles.Ti-substituted samples show highly improved electrode performance as electrode materials.However,the appearance of a sodium-deficient phase,Na4Mn4Ti5O18 with a tunnel-type structure,is observed for Ti-rich phases.Among the samples in this binary system,Na0.8Mn0.8Ti0.2O2(x=0:8),which is a mixture of a partially Ti-substituted O′3-type layered oxide(Na0.88Mn0.88Ti0.12O2)and tunnel-type Na4Mn4Ti5O18 as a minor phase elucidated by Rietveld analysis on both neutron and X-ray diffraction patterns,shows good electrode performance on the basis of energy density and cyclability.Both phases are electrochemically active as evidenced by in situ X-ray diffraction study,and the improvement of reversibility originates from the suppression of Mn dissolution on electrochemical cycles.From these results,the feasibility of Mn-based electrode materials for high-energy rechargeable Na batteries made from only abundant elements is discussed in detail.展开更多
In the article titled“Efficient Stabilization of Na Storage Reversibility by Ti Integration into O′3-Type NaMnO2”[1],there was an error in Figure 4.In panel(a),the“x=0:2”should have read“x=0:8.”This is shown co...In the article titled“Efficient Stabilization of Na Storage Reversibility by Ti Integration into O′3-Type NaMnO2”[1],there was an error in Figure 4.In panel(a),the“x=0:2”should have read“x=0:8.”This is shown corrected in Figure 4 below。展开更多
基金the partial support from Japan Society for the Promotion of Science(JSPS),Grant-in-Aid for Scientific Research(Grant Numbers 15H05701,18H02076,and 19H05816)MEXT program“Elements Strategy Initiative to Form Core Research Center(JPMXP0112101003),”Ministry of Education,Culture,Sports,Science and Technology,Japan.
文摘The development of an energy storage system with abundant elements is a key challenge for a sustainable society,and the interest of Na intercalation chemistry is extending throughout the research community.Herein,the impact of Ti integration into NaMnO2 in a binary system of x NaMnO2–(1–x)TiO2(0:5≤x≤1)is systematically examined for rechargeable Na battery applications.Stoichiometric NaMnO2,which is classified as an in-plane distorted O′3-type layered structure,delivers a large initial discharge capacity of approximately 200 mAhg-1,but insufficient capacity retention is observed,most probably associated with dissolution of Mn ions on electrochemical cycles.Ti-substituted samples show highly improved electrode performance as electrode materials.However,the appearance of a sodium-deficient phase,Na4Mn4Ti5O18 with a tunnel-type structure,is observed for Ti-rich phases.Among the samples in this binary system,Na0.8Mn0.8Ti0.2O2(x=0:8),which is a mixture of a partially Ti-substituted O′3-type layered oxide(Na0.88Mn0.88Ti0.12O2)and tunnel-type Na4Mn4Ti5O18 as a minor phase elucidated by Rietveld analysis on both neutron and X-ray diffraction patterns,shows good electrode performance on the basis of energy density and cyclability.Both phases are electrochemically active as evidenced by in situ X-ray diffraction study,and the improvement of reversibility originates from the suppression of Mn dissolution on electrochemical cycles.From these results,the feasibility of Mn-based electrode materials for high-energy rechargeable Na batteries made from only abundant elements is discussed in detail.
文摘In the article titled“Efficient Stabilization of Na Storage Reversibility by Ti Integration into O′3-Type NaMnO2”[1],there was an error in Figure 4.In panel(a),the“x=0:2”should have read“x=0:8.”This is shown corrected in Figure 4 below。