2026-10-14T16:55:37Z https://api.figshare.com/v2/oai

oai:figshare.com:article/34020598 2026-09-29T03:05:20Z category_15 category_19 category_21 category_24 category_873 portal_63 item_type_6 month_year_09_2026

First Experimental Validation of the Revised Bandgap and Exciton-Limited Photocatalytic H₂ Evolution over CeNbO₄ Jian Liu (33711) Jia Yang (427274) Xiaorui Sun (3093252) Xiaojun Kuang (1527529) Neuroscience Pharmacology Biotechnology Evolutionary Biology Chemical Sciences not elsewhere classified ∼ 100 mev strong excitonic effect photoluminescence measurements confirm first systematic study first experimental validation first baseline data best promotion effect 2 </ sub 4 </ sub pt nanoparticles act exciton binding energy limited photocatalytic h 4 wt limited behavior photocatalytic perspective photocatalytic consequences photocatalytic h work provides uv irradiation true bandgap room temperature revised bandgap remained unexplored pristine sample four times experimentally tested expected absorption electron traps earth niobate actual bandgap 7 μmol 6 μmol The true bandgap of CeNbO₄, a rare-earth niobate, has long been underestimated by conventional Tauc plot analysis. Recent Elliott–Toyozawa exciton modeling revealed an actual bandgap of 3.25 eV and an exciton binding energy of ∼100 meV, shifting the expected absorption from visible to ultraviolet. However, the photocatalytic H₂ evolution performance of CeNbO₄ has remained unexplored, and the photocatalytic consequences of such a strong excitonic effect have never been experimentally tested. Herein, we report the first systematic study of photocatalytic H₂ production over CeNbO₄ under UV irradiation. Pristine CeNbO₄ exhibits a low H₂ evolution rate of 5.6 μmol/h, consistent with the high exciton binding energy (≫kT at room temperature) that severely limits free carrier generation. Among four noble metal cocatalysts (Pt, Au, Ag, Ru), Pt shows the best promotion effect. Optimising Pt loading gives a maximum H₂ evolution rate of 25.7 μmol/h at 4 wt % Pt, four times that of the pristine sample. Photoelectrochemical and photoluminescence measurements confirm that Pt nanoparticles act as electron traps, partially mitigating carrier recombination. This work provides the first baseline data for photocatalytic H₂ evolution over CeNbO₄ and delivers the first experimental validation, from a photocatalytic perspective, of the revised bandgap and exciton-limited behavior of this material. 2026-09-28T00:00:00Z Text Journal contribution 10.1021/acs.jpcc.6c02620.s001 https://figshare.com/articles/journal_contribution/First_Experimental_Validation_of_the_Revised_Bandgap_and_Exciton-Limited_Photocatalytic_H_sub_2_sub_Evolution_over_CeNbO_sub_4_sub_/34020598 CC BY-NC 4.0