Reduced Mo-doped NiCo₂O₄ with rich oxygen vacancies as an advanced electrode material in supercapacitors

Abstract

Reduced Mo-doped NiCo2O4 (R-Mo-NiCo2O4) was facilely prepared through a dual-defect strategy. Mo-doped NiCo layered double hydroxide (Mo-NiCo-LDH) was used as the precursor and calcined in an air atmosphere, and the...

Oxygen vacancy-engineered ultrathin NiCo2O4 nanosheet arrays derived from MOFs as an advanced electrode for supercapacitors

“…Moreover, some lattice distortions and amorphous phases are observed (as indicated by the blue line), which is probably caused by the introduction of oxygen vacancies, and the presence of point defects has a great influence on the electrochemical properties of crystalline materials. 4 The selected area electron diffraction (SAED) pattern (inset of Fig. 1d) suggests typical polycrystalline properties, and the diffraction rings can be well assigned to the crystal planes of NiCo 2 O 4 .…”

“…3 Compared with monometallic Co 3 O 4 or NiO, bimetallic NiCo 2 O 4 shows enhanced electrochemical properties due to higher electronic conductivity and richer valence states. 4 However, most of the reported NiCo 2 O 4 still shows unsatisfactory capacity and serious capacity decay due to the inferior electronic conductivity and slow ion transport. 5 To alleviate these problems, several approaches including morphology manipulation, developing core–shell heterostructures, and hybridizing with conductive materials have been proposed.…”

Modulation of the Proportion of Mixed Metals in Spinel-Type Oxide NixCo3–xO4 (x = 0–1) Derived from a Metal–Organic Framework for Enhanced Oxygen Evolution Reaction

“…Satellite peaks are observed at binding energies of 785.40 and 801.90 eV. O 1s spectra deconvolution exhibited two peaks at 529.10 and 530.80 eV due to the metal–oxygen bond (O1) and defect sites with low oxygen coordination in the material (O2) (Figure c) . The survey scan of NiCo 2 O 4 indicates the formation of NiCo 2 O 4 in the pure form (Figure S10).…”

Overview of the oxygen vacancy effect in bimetallic spinel and perovskite oxide electrode materials for high-performance supercapacitors

“…4A and B show bimetallic spinels (Mo-doped NiCo 2 O 4 and MnCo 2 O 4 @MnO 2 ) soaked in a liquid phase using NaBH 4 reagent. 80,81 After a short time, the oxide materials were reduced, and surface OVs were generated, allowing greater capacitive behavior than their precursor spinel oxide electrodes. The electrochemistry and roles of OVs in spinel electrode materials are discussed in Section 6.…”