Unsaturated Ni/V centers and short Ni·V/Ni distances in nickel vanadate for high-performance zinc-ion battery

3D rotation electron diffraction, Rietveld refinement and spherical aberration-corrected TEM reveal that Ni 0.22 V 2 O 5 (o-NiVO) possesses a novel framework with unsaturated Ni/V centers short ··· V/Ni distances, which shows high capacity, good rate capability long-term durability low Zn 2+ migration barrier. • O-NiVO distances. The structure of o-NiVO is confirmed by diffraction HAADF-STEM. outstanding cyclability. DFT calculations prove barrier in o-NiVO. an intercalation mechanism /H + partial phase transformation. (H O) 0.94 (NiVO) nanobelts were synthesized via facile one-step hydrothermal method, exhibited built [Ni(H 6 ] pillars connecting 2D V-O-V layers. Upon subsequent annealing, large d spacing 9.2 Å obtained. (cRED), displays framework. Annealing led to atom arrangement ions entered into layer (2.463 Å)/Ni ···Ni distances (2.401 Å), can facilitate the transfer from ? improve conductivity (0.64 eV) o-NiVO, as evidenced calculations. Therefore, deliver initial capacity 445 mAh g ?1 at 0.1 A fast diffusion kinetics. Meanwhile, also excellent retention 99.8 % over 1500 discharge/charge cycles. fully discharged was characterized cRED, disclosed structural integrity during discharge process. series ex situ characterizations electrode co(de)intercalation along transformation 3 (OH) 7 .