Boosted photocatalytic NO conversion with inhibited NO2 generation over Nb2O5/g-C3N4 S-scheme heterojunction: nanostructured engineering and mechanism insight
Lin Cheng , Xueying Guo , Jianmin Luo , Ya Xue , Bin Liu , Haitao Ren , Mohsen Padervand , Xiaoyan Yu , Xinglei Wang
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引用次数: 0
Abstract
The critical challenge in the photocatalytic treatment of low-concentration nitrogen oxides (NOx) is to achieve deep oxidation of NO while suppressing the formation of toxic intermediate NO2. Herein, a Nb2O5/g-C3N4 S-scheme heterojunction is designed to address this challenge through tailored charge dynamics. Experimental results and theoretical calculations synergistically validate the S-scheme heterojunction featuring an interfacial electric field (IEF)-driven directional charge separation mechanism. This configuration synergistically enhances charge separation efficiency while maintaining robust redox potentials, thereby effectively activating hydroxyl radicals (OH). As the dominant reactive species, OH facilitates deep oxidation of NO while effectively inhibiting toxic NO2 by-product formation. At an initial NO concentration of 800 ppb, the Nb2O5/g-C3N4 S-scheme heterojunction achieved an excellent removal rate of 68.3 % with suppressed NO2 byproduct generation (24.6 ppb) under visible light irradiation (λ ≥ 420 nm) within 20 min. Furthermore, the reaction intermediates were monitored by in-situ diffused reflection Fourier transform infrared spectroscopy (DRIFTS), identifying nitrate as the terminal oxidation product. This work advances the rational design of S-scheme photocatalysts and offers a viable strategy for environmental remediation of NOx contaminants under visible-light-driven conditions.
期刊介绍:
JPPA publishes the results of fundamental studies on all aspects of chemical phenomena induced by interactions between light and molecules/matter of all kinds.
All systems capable of being described at the molecular or integrated multimolecular level are appropriate for the journal. This includes all molecular chemical species as well as biomolecular, supramolecular, polymer and other macromolecular systems, as well as solid state photochemistry. In addition, the journal publishes studies of semiconductor and other photoactive organic and inorganic materials, photocatalysis (organic, inorganic, supramolecular and superconductor).
The scope includes condensed and gas phase photochemistry, as well as synchrotron radiation chemistry. A broad range of processes and techniques in photochemistry are covered such as light induced energy, electron and proton transfer; nonlinear photochemical behavior; mechanistic investigation of photochemical reactions and identification of the products of photochemical reactions; quantum yield determinations and measurements of rate constants for primary and secondary photochemical processes; steady-state and time-resolved emission, ultrafast spectroscopic methods, single molecule spectroscopy, time resolved X-ray diffraction, luminescence microscopy, and scattering spectroscopy applied to photochemistry. Papers in emerging and applied areas such as luminescent sensors, electroluminescence, solar energy conversion, atmospheric photochemistry, environmental remediation, and related photocatalytic chemistry are also welcome.