Formation of Hierarchical Structure Composed of (Co/Ni)Mn-LDH Nanosheets on MWCNT Backbones for Efficient Electrocatalytic Water Oxidation

Abstract

Active, stable, and cost-effective electrocatalysts are attractive alternatives to the noble metal oxides that have been used in water splitting. The direct nucleation and growth of electrochemically active LDH materials on chemically modified MWCNTs exhibit considerable electrocatalytic activity toward oxygen evolution from water oxidation. CoMn-based and NiMn-based hybrids were synthesized using a facile chemical bath deposition method and the as-synthesized materials exhibited three-dimensional hierarchical configurations with tunable Co/Mn and Ni/Mn ratio. Benefiting from enhanced electrical conductivity with MWCNT backbones and LDH lamellar structure, the Co5Mn-LDH/MWCNT and Ni5Mn-LDH/MWCNT could generated a current density of 10 mA cm(-2) at overpotentials of ∼300 and ∼350 mV, respectively, in 1 M KOH. In addition, the materials also exhibited outstanding long-term electrocatalytic stability.

One‐Step Synthesis of Ultrathin NiMn Layered Double Hydroxide Nanosheets for Supercapacitors

“…When hydroxyl act as weak field ligands, Mn 3 + are in the high spin state, which leading to instability of NiMn LDH, Mn 3 + are easily oxidized to Mn 4 + , we can also observe that the characteristic peak of Mn 4 + exists at 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 around 647 eV. [28,[35][36][37] Additionally, the EDS mapping of UNML nanosheets ( Figure S2a-d) shows the homogeneous distribution of Ni, Mn and O elements.…”

Layered double hydroxides/reduced graphene oxide nanocomposites with enhanced barrier properties

“…The disappeared (001) peaks in LDH‐rGO may be due to the uniformly dispersion of graphene sheets and the very low content of GO. Moreover, compared with pure LDHs, a decrease in the intensity of the (003) reflection peak in LDH‐rGO hybrids shows a disordered layered structure .…”

Recent Applications of 2D Inorganic Nanosheets for Emerging Energy Storage System

“…The high OER catalytic activity of this material was attributed to the strong interaction of LDH with CNT through the formation of M‐O‐C (M=Ni, Fe) bonds, leading to the promotion of charge transport. Similar studies on hybridization of LDHs with conductive carbon materials have been reported, such as Ni‐Fe‐LDH/graphene composite, Co‐Mn‐LDH/CNT composite, (Co/Ni)‐Mn‐LDH/CNT composite, Ni‐Co‐LDH/carbon paper . The 2D nanosheets of TMOs, TMDs, and transition metal phosphides with high surface area and defects have also been used as efficient OER electrocatalysts.…”