Structural analysis by synchrotron X-ray diffraction, X-ray absorption fine structure and transmission electron microscopy for aluminum-substituted α-type nickel hydroxide electrode

Electrochemical properties of nickel–aluminum layered double hydroxide/carbon composite fabricated by liquid phase deposition

“…It rapidly increases and reaches its maximum at the 8th cycle, then starts fading from the 20th cycle. A similar cycle performance was obtained for 20 Al% by Morishita et al [55]. The discharge capacity of the electrode with 13.8 Al% starts at 360 mAh g comp −1 , reaches its maximum at the 50th cycle and ends up with a constant value of 376.7 mAh g comp −1 .…”

“…Another hypothesis supporting the good performance of the electrode with 17.8 Al% could be a better balance between intercalated anions and water molecules within the interlayer space of ␣-Ni(OH) 2 lattice, which might be favorable to the proton diffusion during charge-discharge processes [24,26]. The optimal Al content of 17.8% found in this work is so close to those obtained within the range 18.3-20.4 Al% by different methods [26,[53][54][55][56]. The origin of the second discharge voltage plateau has been investigated by several authors.…”

“…In most of cases, electrodes made with active materials containing 10-15 Al% display poor performance because they are instable in strong alkali. Therefore, the interval 18.3-20.4 Al% appears to be the suitable range of Ni substitution when the materials are prepared with different methods [26,[53][54][55][56]. This finding implies that the control of the Al 3+ content depends on the preparation method.…”

Nickel–Aluminum Layered Double Hydroxide Coating on the Surface of Conductive Substrates by Liquid Phase Deposition

“…The introduction of trivalent cations, such as Al 3+ ion, to the LDH main frame contributes to the stabilization of the α-phase of nickel hydroxide and the improvement of the electrochemical characteristics (e.g., electron and ion conductivities). 4,8,12,13 Therefore, SEM-EDX spectroscopy was employed in this work. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 of substrates.…”

Synthesis and electrochemical performance of α-nickel hydroxide codoped with Al3+ and Ca2+

“…This feature indicates that the Al 3+ /Ca 2+ codoped sample contains many water molecules, which may accelerate the proton-migration rate. The water molecules contained in the interlayer also improve discharge capacity [13]. In addition, the (003) peak position of Al 3+ /Ca 2+ codoped a-nickel hydroxide is 11.16°, which is slightly larger than that (10.91°) of Al 3+ singly doped a-nickel hydroxide.…”