Loading…

Visible-light-driven aldehyde ammoxidation to nitrile via •O2– and •NHx radicals generation over Ni(OH)2/TiO2 p-n heterojunctions

[Display omitted] •Nitriles were synthesized by utilizing visible-light as the only energy input.•Driving aldehyde ammoxidation with NH3·H2O as nitrogen source at mild conditions.•Ni(OH)2/TiO2 p-n heterojunctions exhibit unique properties in nitrile synthesis.•Visible-light-generated holes are capab...

Full description

Saved in:
Bibliographic Details
Published in:Journal of catalysis 2025-02, Vol.442, Article 115897
Main Authors: Zhou, Yiwei, Zhao, Jian, Guo, Hairui, Wang, Cheng
Format: Article
Language:English
Subjects:
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:[Display omitted] •Nitriles were synthesized by utilizing visible-light as the only energy input.•Driving aldehyde ammoxidation with NH3·H2O as nitrogen source at mild conditions.•Ni(OH)2/TiO2 p-n heterojunctions exhibit unique properties in nitrile synthesis.•Visible-light-generated holes are capable of activating NH3 to ⋅NHx radicals.•⋅NHx and ⋅O2– play different roles in forming aldimine intermediate and nitriles. Aldehydes ammoxidation is a green and promising route for selective synthesis of nitrile, but developing low-cost and efficient catalytic system under mild condition remains a challenge. Herein, we explore a novel catalytic system where the designed Ni(OH)2/TiO2 p-n heterojunction catalyst could efficiently drive aldehydes ammoxidation with NH3·H2O and O2 at ambient temperature and pressure by using visible-light as the only energy input. The superoxide (•O2–) generated by reducing O2 with photogenerated electrons and amino radicals (•NHx) produced by oxidizing NH3·H2O with photogenerated holes, are successfully identified as key species for the formation of nitriles. Meanwhile, •NHx and •O2– radicals individually work on the formation of the intermediate aldimine intermediate and its oxidation to nitrile. The performance of the engineered Ni(OH)2/TiO2 p-n heterojunctions in the reaction process is much more superior to other catalyst systems. This study develops nitrile synthesis route under mild conditions and present new opportunities for constructing low-cost photocatalyst for chemical synthesis. It also provides a better understanding of the radical species and how they work in aldehydes ammoxidation reactions.
ISSN:0021-9517
DOI:10.1016/j.jcat.2024.115897