LaFeO3 Modified with Ni for Hydrogen Evolution via Photocatalytic Glucose Reforming in Liquid Phase

Abstract

In this work, the optimization of Ni amount on LaFeO3 photocatalyst was studied in the photocatalytic molecular hydrogen production from glucose aqueous solution under UV light irradiation. LaFeO3 was synthesized via solution combustion synthesis and different amount of Ni were dispersed on LaFeO3 surface through deposition method in aqueous solution and using NaBH4 as reducing agent. The prepared samples were characterized with different techniques: Raman spectroscopy, UltraViolet-Visible Diffuse Reflectance Spettroscopy (UV–Vis-DRS), X-ray Diffraction (XRD), X-ray Photoelectron Spectroscopy (XPS), X-ray Fluorescence (XRF), Transmission Electron microscopy (TEM), and Scanning Electron microscopy (SEM) analyses. For all the investigated photocatalysts, the presence of Ni on perovskite surface resulted in a better activity compared to pure LaFeO3. In particular, it is possible to identify an optimal amount of Ni for which it is possible to obtain the best hydrogen production. Specifically, the results showed that the optimal Ni amount was equal to nominal 0.12 wt% (0.12Ni/LaFeO3), for which the photocatalytic H2 production was equal to 2574 μmol/L after 4 h of UV irradiation. The influence of different of photocatalyst dosage and initial glucose concentration was also evaluated. The results of the optimization of operating parameters indicated that the highest molecular hydrogen production was achieved on 0.12Ni/LaFeO3 sample with 1.5 g/L of catalyst dosage and 1000 ppm initial glucose concentration. To determine the reactive species that play the most significant role in the photocatalytic hydrogen production, photocatalytic tests in the presence of different radical scavengers were performed. The results showed that •OH radical plays a significant role in the photocatalytic conversion of glucose in H2. Moreover, photocatalytic tests carried out with D2O instead of H2O evidenced the role of water molecules in the photocatalytic production of molecular hydrogen in glucose aqueous solution.

Phase-Pure High-Entropy Spinel Oxide (Ni,Fe,Mn,Cu,Zn)3O4 via Thermal Plasma: A Promising Electrocatalyst for Oxygen Evolution Reaction

“…Moreover, to gain insights into the morphology of HEO@350 °C, HRTEM analysis was carried out, and the respective results are provided in Figure . The low to high magnified HRTEM images in Figure a,b depict that the particles are found to be aggregated and appear as nearly spherical shapes and well agreed with the FESEM result . The SAED pattern shown in Figure c confirms the polycrystalline nature with corresponding diffraction rings belonging to the (111), (222), (422), and (440) planes of HEO@350 °C.…”

Preparation of visible-light active MOFs-Perovskites (ZIF-67/LaFeO3) nanocatalysts for exceptional CO2 conversion, organic pollutants and antibiotics degradation

“…5 A. Additionally, Fig. 5 B shows DRS spectrum of fabricated composites, indicating that pristine LFO-NS emits light at 340 nm, validating the band gap at 2.0 eV [ 48 ]. Meanwhile, the band gap relocated to the visible area upon integrating with different mass percentage ratios of ZIF-67 to LFO-NS.…”

Fe/Ni redox synergistic sodium persulfate photocatalytic depolymerization of the sinocalamus oldhami alkali lignin for the directional synthesis of aromatic aldehydes

“…2e, the binding energies of 709.78-710.38 eV and 723.88-724.28 eV corresponded to Fe 2p 3/2 and Fe 2p 1/2 states. It was indicated that the concentration of Fe 2p ions in LFNO-0.1 was higher than LFO [17]. Owing to the existence of oxygen vacancies, partial conversion of Fe 3p ions into Fe 2p ions compensated for the electrical neutrality in the system.…”