N‐doped Nanocarbon Inserted NiCo‐LDH Nanoplates on NF with High OER/ORR Performances for Zinc‐Air Battery

Abstract

Herein, a high performance bifunctional catalyst was prepared by inserting N‐doped nanomaterials into Ni−Co layered dihydroxides (NiCo‐LDH) nanoplates for high performance zinc‐air battery. By using self‐assembly of perylenetetracarboxylic dianhydride and dicyandiamide in the hydrothermal condition, a nitrogen‐containing super thin carbonaceous nanosheet is achieved after calcination. Then NCM inserted NiCo‐LDH nanoplates attached to nickel foam (NiCo‐LDH/NCM@NF) are synthesized by in‐situ production of NiCo‐LDH species on NCM wrapped NF. The specific NCM improves the conductivity, electroactive surface area and the ORR/OER bifunctional activity of NiCo‐LDH nanoplates. In addition, benefited from the formed rich oxygen vacancies, NiCo‐LDH/NCM@NF delivers the low OER overpotential (352 mV at 50 mA cm−2) and boosted ORR performance with a half‐wave potential of 0.765 V vs RHE. As the air cathode, the fabricated ZAB devices show a satisfactory capacity of 685 mAh g−1 and the energy density of 158 mW cm−2.

Ultrathin Sulfur‐Doped g‐C3N4 Nanosheets Controlled by Steam Activation for Enhanced Visible‐Light Photocatalytic Performance

“…The characteristic diffraction peak at 14°c orresponds to the (100) plane of g-C 3 N 4 belonging to the inplane repeating unit of g-C 3 N 4 . [31] The intense diffraction peak at 27°corresponds to the (002) plane of g-C 3 N 4 , which is the repeating unit of the aromatic layered structure. [32] The intensity of the (100) plane peak of CNÀ S-X decreases compared to that of CN and CNÀ S, indicating the presence of numerous structural defects in CNÀ S-X after steam activation treatment.…”

Bifunctional 2D structured catalysts for air electrodes in rechargeable metal-air batteries

“…The assembled ZAB exhibited a promising peak power density (92.3 mW cm -2 ), and only a negligible voltage loss was found after continuous operation for 50 h. Oxygen vacancies modify the structure of active materials on an electrode/ electrolyte interface without sacrificing the crystal stability [140,141] , and experimental and DFT calculations have demonstrated that oxygen vacancies enhance the activity of a material for oxygen reactions [142] . Furthermore, for atomic adjustment, the core principle is optimizing the electronic structure at the active site [143,144] . For example, Han et al configured atomic-level sulfur-incorporated NiFe-LDHs that were deposited in situ on nitrogen-doped graphene (S-LDH/NG) [Figure 6D] [51] ; the atomic-level sulfur incorporation resulted in a customized topological microstructure and adjusted electronic structure, leading to enhanced catalytic activity and durability of bifunctional electrocatalyst.…”

Sustainable zinc–air battery chemistry: advances, challenges and prospects

“…Hydroxides and LDHs are generally active for the OER, while relatively less active for the ORR. 155,156 In this case, their poor ORR activity can be addressed by coupling functional carbon supports with good ORR activity. 117 Meanwhile, the conductive carbon network constructs an electron pathway for hydroxides/ LDHs to significantly boost the OER.…”