Amorphous Ni–P materials for high performance pseudocapacitors

New asymmetric and symmetric supercapacitor cells based on nickel phosphide nanoparticles

“…But the energy density of Ni 2 P//Ni 2 P SSCs can be only 0.24 Wh kg À1 at a power density of 42 W kg À1 . Meanwhile, the energy density of the present Ni 2 P//AC ASCs is about 2.2 times as much as that of asymmetric supercapacitors based on amorphous NieP compounds and AC (29.2 Wh kg À1 at a power density of 400 W kg À1 ) [32]. Thus, although the performance of present Ni 2 P nanoparticle is similar to that of amorphous NieP or pure Ni 2 P in terms of voltage window and cyclic stability, the present Ni 2 P nanoparticles were successfully applied in a full-cell supercapacitors which show higher energy density of 64.6 Wh kg À1 at a power density of 1029 W kg À1 .…”

“…Furthermore, as far as we know, there are fewer reports of Ni 2 P nanomaterials applied in ASCs. Until recent, amorphous NieP materials were synthesized and applied as the positive electrodes of ASCs [32]. This type of ASCs can deliver an energy density of 11.8 Wh kg À1 at a power density of 8000 W kg À1 .…”

Metal Phosphides and Phosphates‐based Electrodes for Electrochemical Supercapacitors

“…For example, white phosphorus has been used as the precursor in the solvothermal process to prepare Ni 2 P nanoparticles . NiP has been achieved by a facile solvothermal method, where NaH 2 PO 2 ·H 2 O and NiCl 2 ·6H 2 O are dissolved in DI water or DMF . The resultant metal phosphides vary in structures, ranging from NiP microspheres to NiP porous structure .…”

“…NiP has been achieved by a facile solvothermal method, where NaH 2 PO 2 ·H 2 O and NiCl 2 ·6H 2 O are dissolved in DI water or DMF . The resultant metal phosphides vary in structures, ranging from NiP microspheres to NiP porous structure . Depending on the requirement for the type of electrode material, surfactants can be added into the solution for better control or adjustment in nanostructures/mesostructures.…”

“…As a class of pseudocapacitive materials, different phases of nickel phosphides have been developed, including Ni 12 P 15 , amorphous NiP, Ni 2 P, and Ni 5 P 4 . For better pseudocapacitive performance, considerable efforts have been made with controlling of their morphologies.…”