Strong Fe3+-O(H)-Pt Interfacial Interaction Induced Excellent Stability of Pt/NiFe-LDH/rGO Electrocatalysts

Abstract

Agglomeration-triggered deactivation of supported platinum electrocatalysts markedly hinders their application in methanol oxidation reaction (MOR). In this study, graphene-supported nickel–iron layered double hydroxide (NiFe-LDH/rGO), in which Fe3+ was introduced to replace Ni2+ partially in the Ni(OH)2 lattice to provide stronger metal–support bonding sites, was utilized to immobilize Pt nanoparticles (NPs). Given the optimized metal–support interfacial contact (Fe3+-O(H)-Pt) between Pt NPs and NiFe-LDH/rGO nanosheets for Pt/NiFe-LDH/rGO electrocatalysts, the Pt/NiFe-LDH/rGO electrocatalysts displayed dramatically enhanced durability than that of Pt/Ni(OH)2/rGO counterpart as well as commercial Pt/C, and 86.5% of its initial catalytic activity can be maintained even after 1200 cycles of cyclic voltammetry (CV) tests during MOR. First-principle calculations toward the resultant M-O(H)-Pt (M = Fe3+, Ni2+) interfacial structure further corroborates that the NiFe-LDH nanosheets can provide stronger bonding sites (via the Fe3+-O(H)-Pt bonds) to immobilize Pt NPs than those of Ni(OH)2 nanosheets (via the Ni2+-O(H)-Pt bonds).

Sub-Nanometer Pt Clusters on Defective NiFe LDH Nanosheets as Trifunctional Electrocatalysts for Water Splitting and Rechargeable Hybrid Sodium–Air Batteries

“…High-magnification HAADF-STEM and TEM images indicated that uniformly dispersed ultrafine Pt NCs on the defect-rich NiFe LDH nanosheet surface with a narrow particle-size distribution (Figure 2c−f). Notably, TEM images showed that nanosheets treated with strong alkaline had a negligible change in the size distribution of Pt NCs except for the thinner nanosheets structure, 8,16 The highresolution TEM (HRTEM) illustrated that lattice fringes were coherently extended over the entire nanoparticle, confirming the formation of a single-crystal structure (Figure 2e), which was consistent with the selected area electron diffraction (SAED) pattern (inset of Figure 2c). The lattice spacing of 0.226 nm corresponded to the (111) planes of fcc Pt, 20 which was consistent with the XRD investigation.…”

“…The adsorption energy of Pt NCs via the Fe 3+ − O(H)−Pt bonding was −4.87 eV, which was lower than that of Ni 2+ −O(H) −Pt bonding (−4.61 eV), suggesting the strong interaction of Pt NCs with site-specific Ni x Fe LDH sheets, which was consistent with previous studies. 16 Therefore, the Pt/Ni x Fe LDHs electrode displayed remarkable catalytic stability compared with that in the absence of the Fe precursor (Figure S16d). The observed slopes indicated that the ECSA was increased obviously after introducing a small amount of Fe elements while excessive usage led to negative effects (Figure S16e), which agreed well with the electrocatalytic performance.…”

Layered double hydroxide-based electrocatalysts for the oxygen evolution reaction: identification and tailoring of active sites, and superaerophobic nanoarray electrode assembly

“…A study by Liang and Liu provided additional guidance from the computational perspective on the bonding sites to immobilize noble metal atoms. 171 A model consisting of Pt and NiFe-LDHs, as shown in Fig. 13f, was constructed to elucidate the trend of the Pt The theoretical calculation revealed that Pt tended to bond with Fe 3+ ; therefore, the interaction between Fe 3+ and Pt was responsible for the site-specific loading and enhanced electrocatalytic activity of Pt-NiFe-LDHs.…”

“…Copyright 2017, Elsevier Ltd. (f) Atomic structure of the Pt atom bonding to the ferric site in NiFe-LDHs. Reproduced with permission 171. Copyright 2018, the authors.…”

Superactive NiFe-LDH/graphene nanocomposites as competent catalysts for water splitting reactions

“…Solid NiFe-LDH, possesses strong interplane chemical bonds but weaker out-of-plane van der Waals forces. 111 NiFe-LDH can be exfoliated and self-assembled with other layered materials like graphene, such as g-C 3 N 4 and MoS 2 , to form heterostructured materials. We have also reported different heterostructured materials of NiFe-LDH by the exfoliation strategy, composited with other layered materials such as in g-C 3 N 4 /NiFe-LDH, 27 Ag@Ag 3 PO 4 /g-C 3 N 4 / NiFe-LDH, 62 g-C 3 N 4 /N-rGO/NiFe-LDH, 33 and MoS 2 /NiFe-LDH.…”