Orthorhombic Nb2O5(T-Nb2O5),a typical intercalation pseudocapacitor,is favorable for realizing high power and energy density for lithium-ion batteries;furthermore,the 2D layered channels perpendicular to the[001]direction facilitate fast Li+ intercalation in T-Nb2O5.Herein,N-doped T-Nb2O5 microflowers(N-Nb2O5)assembled from highly[001]-oriented nanoflakes are rationally synthesized using NH4F as the nitrogen source and capping agent.It is found that NH4+ can adsorb on the O-terminated(010)plane of T-Nb2O5 via N-H···O hydrogen bonds,which is highly conducive to the generation of 1D nanorods and the subsequent fusion of the nanorods into highly[001]-oriented nanoflakes.The special growth orientation of the T-Nb2O5 nanoflakes endows them with abundant available Li+ intercalation channels;moreover,the bandgap of N-Nb2O5 is narrowed(~2.91 eV)owing to the doping of N atoms,and the intrinsic electronic conductivity is improved.Accordingly,the intercalation pseudocapacitive behavior of N-Nb2O5 is notably promoted and N-Nb2O5 exhibits superior Li+ storage properties,including large discharge capacity(214.7 mA h g~(-1)at 1C),excellent rate capability(203.7 and 174.6 mA h g~(-1)at 1 and 20C),and superior cyclic stability(150.7 mA h g~(-1)at 10C after 1000 cycles).In addition,the LiNi_(0.5)Mn_(0.3)Co_(0.2)O2//N-Nb2O5 full cell delivers outstanding Li+ storage performance,especially in terms of long-term cycling(126.2 mA h g~(-1)at 10C after 3500 cycles).
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