Facile Synthesis of Nanostructured Binary Ni–Cu Phosphides as Advanced Battery Materials for Asymmetric Electrochemical Supercapacitors

Abstract

Transition-metal phosphides (TMPs) enjoy metalloid characteristics with good electrical conductivity, making them potential candidates for electrochemical supercapacitors. However, TMPs are difficult to synthesize by conventional methods, limiting their practical use in a plethora of applications. Herein, we demonstrate the successful fabrication of Ni–Cu binary phosphides (NCP) via a one-step, facile solvothermal method. More importantly, the correlation between the degree of phosphidation and the electrochemical behavior of the material is explored and discussed. The NCP electrode exhibited a battery-like behavior with an ultrahigh specific capacitance (C s) of 1573 F g–1 at 1 A g–1. Upon use as a positive electrode, it showed superior performance in a hybrid supercapacitor device with bioderived activated carbon (BAC) as the negative electrode (NCP//BAC), providing a high energy density of 40.5 W h kg–1 at 875 W kg–1 with exceptional capacity retention after 10,000 cycles. These values are 4 times higher than that of commercial supercapacitors (10–12 W h kg–1), suggesting the unique supercapacitance performance of the NCP//BAC device compared to the phosphide-based devices reported so far.

Synergistically enhanced performance of transition-metal doped Ni2P for supercapacitance and overall water splitting

“…Nickel phosphides continue to attract attention as catalysts in water splitting and supercapacitance applications. [6][7][8] The growing attention is due to their abundant earth reserves, high electrical conductivity, fast charge transfer, and good reaction kinetics. 9 Nickel phosphide is a binary system with multiple compositions or phases depending on the ratio of nickel to phosphorus in the system.…”

Quaternary Cu2FeSnS4/PVP/rGO Composite for Supercapacitor Applications

“…Supercapacitors and batteries are a potential source of energies for practical use, while principle energy sources can be exhausted. 3 , 4 Recently, supercapacitors have attracted a lot of interest due to their physicochemical characteristics because of double-layer capacitor (EDLC) or pseudocapacitor charge-storage mechanisms. 5 , 6 Pseudocapacitors are having high storage and on the other hand having low cyclic rate, whereas EDLC materials as carbon-based electrode materials exhibit excellent cyclability.…”

A mesoporous ternary transition metal oxide nanoparticle composite for high-performance asymmetric supercapacitor devices with high specific energy

“…The CVs show a deviation from EDL behaviour, proposing that the produced capacitance of the electrode is a contribution of EDL and pseudo behaviours of Ti and Please do not adjust margins Please do not adjust margins Mo, respectively with the redox of Ni as Ni +2 / Ni 3+ . At high scan rate, the CVs sustain the same behaviour 31,34 . The calculated specific capacitance was found to be 255.4 F.g -1 , which is the highest among all titanium-based electrodes reported so far in the literature 9,25,33. Additionally, the galvanic charge/discharge (GCD) data plotted in Fig.…”

“…Reference source not found.d 29 . Furthermore, Ni 2p peaks can be fitted into four peaks at ~856 and 873.7 eV corresponding to Ni 3+ as well as 852.4 and 869.6 eV assigned to Ni 30,31 as shown in Fig. 2Error!…”

“…The TMN NPs//MPDC cell delivered a high specic energy of 68.47 W h kg À1 at a current density of 1 A g À1 with a corresponding specic power of 2058 W kg À1 , which is higher than those reported in the literature. 29,31,[39][40][41]…”