Metal–Organic Framework-Derived Fe-Doped Ni₃Se₄/NiSe₂ Heterostructure-Embedded Mesoporous Tubes for Boosting Oxygen Evolution Reaction

Abstract

It is crucial but challenging to promote sluggish kinetics of oxygen evolution reaction (OER) for water splitting via finely tuning the hierarchical nanoarchitecture and electronic structure of the catalyst. To address such issues, herein we present iron-doped Ni 3 Se 4 /NiSe 2 heterostructure-embedded metal− organic framework-derived mesoporous tubes (Ni-MOF-Fe-Se-400) realized by an interfacial engineering strategy. Due to the hierarchical nanoarchitecture of conductive two-dimensional nanosheet-constructed MOF-derived mesoporous tubes, coupled with fine tuning of the electronic structure via Fe-doping and interactions between Ni 3 Se 4 /NiSe 2 heterostructures, the Ni-MOF-Fe-Se-400 catalyst delivers superior OER activity: it requires only a low overpotential of 242 mV to achieve 10 mA cm −2 (E j=10 ), surpassing the benchmark RuO 2 (E j=10 = 286 mV) and displays exceptional durability in the chronoamperometric i−t test with a small current decay (6.2%) after 72 h. Furthermore, the water splitting system comprises a Ni-MOF-Fe-Se-400 anode and a Pt/C cathode requires a low cell voltage of 1.576 V to achieve E j=10 with an excellent Faradic efficiency (∼100%), outperforming the RuO 2 −Pt/C combination. This work presents a novel interfacial engineering strategy to finely adjust the morphology and electronic structure of the non-noble metal-based OER catalyst via a facile fabrication method.

MOF-Derived Co3S4 Nanoparticles Embedded in Nitrogen-Doped Carbon for Electrochemical Oxygen Production

“…Figure a presents the C dl values of Co 3 S 4 -2h, Co 3 S 4 -3h, and Co 3 S 4 -4h at 1.17 V vs RHE. Co 3 S 4 -3h has a higher C dl value of 25.23 mF cm –2 compared to Co 3 S 4 -2h (8.55 mF cm –2 ) and Co 3 S 4 -4h (6.01 mF cm –2 ), demonstrating the availability of larger electrochemically active sites for the OER to occur . Interestingly, the ECSA results were closely related to the specific surface area analysis of the Co 3 S 4 -T products obtained from the BET data.…”

Flexible electrode of Fe-doped NiSe2@porous graphene as binder-free anode for lithium-ion batteries

“…And the peak at 59.1 eV could come from Se–O. 43–45 Similar to the Ni 2p spectra, the binding energies of Se 3d for Fe-NiSe 2 @PG were also higher than that for NiSe 2 @PG, which may be due to the charge transfer from nickel and iron to selenium. 46,47 Consequently, doping with Fe may provide more active sites for lithium ion storage.…”

“…Corresponding satellite peaks are located at 878.6 eV and 860.2 eV. 40–45 However, compared with NiSe 2 @PG, the Ni 2p (including Ni 3+ 2p 1/2 , Ni 2+ 2p 1/2 , Ni 3+ 2p 3/2 , and Ni 2+ 2p 3/2 ) of Fe-NiSe 2 @PG presents upshifts to higher binding energies of about 0.1 eV, indicating that the Fe doping changes the electrical structure of NiSe 2 and increases the binding energy of Ni 2p. 46,47 To further analyze the effect of iron doping on the interfacial interaction between graphene and NiSe 2 , the Se 3d spectra were investigated in detail (Fig.…”

Defect‐Engineered Mesoporous Undoped Carbon Nanoribbons for Benchmark Oxygen Reduction Reaction

“…[40] Moreover, the Raman spectral data of metal-free carbon nanomaterials exhibited the graphitic carbon-related D (≈1338 cm −1 ; edge-associated out-of-plane vibrations of sp 2 carbon) and G (≈1598 cm −1 ; in-plane vibrations of sp 2 carbon) bands, approving the formation of defective graphitic carbon (Figure 2i). [47,48] In general, the I D /I G ratio describes the possibility of intrinsic defects in a material, and the higher I D /I G value indicates a large number of edge and intrinsic defects. [31] Notably, NR-900 displayed a high degree of I D /I G value, supporting the increased defective sites via holes and edge generation in the obtained graphitic carbon compared to the other control samples.…”