Inheritable Organic‐Inorganic Hybrid Interfaces with π–d Electron Coupling for Robust Electrocatalytic Hydrogen Evolution at High‐Current‐Densities

Abstract

Rational heterointerface engineering is crucial for superior and robust hydrogen evolution reaction (HER). Herein, a delicate organic-inorganic hybrid heterojunction based on the assembly of oxalate with polyaniline (PANI) for HER at high-current-densities is envisioned. Strong π-d electron coupling is achieved between the delocalized π electrons of PANI and the localized d electrons of oxalate metal sites. The CoC 2 O 4 nanosheets are grown on nickel foam (NF) with Ni 2+ ions substitution by the precursor etching. By virtue of the synergy of hetero ions and π-d electron coupling, metal sites obtain sufficient exposure and electronic structure optimization. Surprisingly, the phase transition of oxalate during HER in the alkaline environment does not weaken the π-d electronic coupling of the organicinorganic hybrid interfaces. Inheritable interfacial electron interaction provides a reliable guarantee for robust stability at high-current-densities while endowing the hybrid materials with extremely low overpotentials. As expected, post-phase reconstructed Co 0.59 Ni 0.41 (OH) 2 @PANI/NF displays impressive HER activity, with a low overpotential of 43 mV@−10 mA cm −2 and robust stability at −1000 mA cm −2 for 30 h in the alkaline environment. This study sheds light on the rational heterostructure interface design and promotes the architecture of an impressive electrocatalysts system.

Rational design of efficient electrocatalysts for hydrogen production by water electrolysis at high current density

“…For instance, Zhao et al designed the heterointerface between inorganic Co 0.59 Ni 0.41 C 2 O 4 and organic polyaniline (PANI) using the hydrothermal method and subsequent electrodeposition. 103 XPS and EXAFS analysis results confirmed the existence of π-d electron coupling at the heterointerface of the Co 0.59 Ni 0.41 C 2 O 4 @PANI composite. DFT calculations indicated that π-d electron coupling can unshift the d-band center of Co, enhance water adsorption and activation and optimize the H* binding energy, thus enhancing the HER activity.…”

“…(f) The surface reconstruction of electrocatalysts with the organic-inorganic heterointerface. 103 Copyright 2023, Wiley-VCH. cannot be overlooked for the practical application of the AEMWE.…”

Synergistic Interface Engineering of RuO2/Co3O4 Heterostructures for Enhanced Overall Water Splitting in Acidic Media

“…[34,35] The electron paramagnetic resonance (EPR) spectra in Figure 2b [25,36] Oxygen vacancies in RuO 2 /Co 3 O 4 play important roles in surface synergistic heterocatalytic reactions, which adsorb activated reactant molecules and optimize the interface structure between metal and carrier, leading to the improvement of electrocatalytic performance in water splitting. [36][37][38] To gain a deeper insight into the electron transfer behavior between RuO 2 and Co 3 O 4 , an ultraviolet photoelectron spectrometer (UPS) test was performed to calculate the work function of pure Co 3 O 4 and RuO 2 /Co 3 O 4 (Figure 2c). [39] As shown in Figure 2c, the measured secondary electron cutoff energy (E cutoff ) of RuO 2 /Co 3 O 4 and Co 3 O 4 are 16.98 and 16.66 eV, respectively.…”

Ni−CeO2 Heterostructure Promotes Hydrogen Evolution Reaction via Tuning of the O−H Bond Length of Adsorbed Water at the Electrolyte/Electrode Interface

“…Additional references cited within the Supporting Information. [36,[59][60][61][62][63][64][65][66][67][68][69][70][71][72][73][74][75][76]…”