Magnetic‐Field‐Stimulated Efficient Photocatalytic N₂ Fixation over Defective BaTiO₃ Perovskites

Abstract

Efficient coupling solar energy conversion and N 2 fixation by photocatalysis has been shown promising potentials.H owever,t he unsatisfied yield rate of NH 3 curbs its forwarda pplication. Defective typical perovskite,B aTiO 3 , shows remarkable activity under an applied magnetic field for photocatalytic N 2 fixation with an NH 3 yield rate exceeding 1.93 mg L À1 h À1 .T hrough steered surface spin states and oxygen vacancies,t he electromagnetic synergistic effect between the internal electric field and an external magnetic field is stimulated. X-raya bsorption spectroscopya nd density functional theory calculations reveal the regulation of electronic and magnetic properties through manipulation of oxygen vacancies and inducement of Lorentz force and spin selectivity effect. The electromagnetic effect suppresses the recombination of photoexcited carriers in semiconducting nanomaterials, which acts synergistically to promote N 2 adsorption and activation while facilitating fast charge separation under UVvis irradiation.

Photocatalytic Nitrogen Reduction Reaction over Two-Dimensional Cs3Bi2Br9–CdS Van der Waals Heterostructures by External Control Strategies

“…Ammonia (NH 3 ) is an essential chemical substance. − As an important precursor of nitrogen-containing compounds, a small part of diazotrophs in nature can directly fix atmospheric N 2 into biologically useable ammonium. − However, it is still difficult to meet the great demand of the current fertilizer industry. The Haber–Bosch process can reduce N 2 to NH 3 under high temperature and high pressure conditions with iron-based catalysts. − However, it has taken more than 1% of the total global energy consumption because H 2 used in this process is obtained through the steam reforming of fossil fuels, and this process accounts for 1.6% of the total global CO 2 emissions. , Considering the challenges to energy and environment, researchers have devoted to develop alternatives to fix N 2 under mild conditions. , With the advances in eco-friendly solar energy, photocatalysis has become a focus on energy and chemical fuel production. , Since the groundbreaking research on photocatalytic nitrogen reduction reaction (NRR) reported in 1977, it has been regarded as an efficient and eco-friendly strategy for NH 3 synthesis, providing the advantages of good controllability and mild reaction conditions (room temperature and environmental pressure) …”

The Spin Modulation Stimulated Efficient Electrocatalytic Oxygen Evolution Reaction over LaCoO3 Perovskite

“…This result suggests that with the prolongation of thermal reduction time, the conductivity was firstly enhanced and then reduced. Additionally, the electrochemical impedance spectroscopy (EIS) measurements were further carried out in 0.5 M KOH electrolyte to evaluate the reaction kinetics [45,46] . Figure 5b shows the Nyquist plots of LCO and LCO‐X.…”

Photocatalytic nitrogen reduction to ammonia: Insights into the role of defect engineering in photocatalysts

“…This emerging scheme has been recently combined with defect engineering in photocatalytic N2 reduction. A remarkably high NH3 yield rate exceeding 1.93 mg•L −1 •h −1 was attained over defective BaTiO3 under an applied magnetic field [323]. Such significant enhancement was mainly attributed to boosted N2 adsorption by oxygen vacancies and suppression of photoexcited carriers recombination arising from an electromagnetic synergistic effect between the internal electric field of the photocatalyst and an external magnetic field.…”