Vu Manh-Hiep, Nguyen Chinh-Chien, Do Trong-On
Department of Chemical Engineering, Laval University, Quebec, Quebec G1V 0A6, Canada.
Institute of Research and Development, Duy Tan University, Da Nang 550000, Vietnam.
ACS Sustain Chem Eng. 2020 Aug 17;8(32):12321-12330. doi: 10.1021/acssuschemeng.0c04662. Epub 2020 Jul 21.
Photoelectrochemical (PEC) nitrogen fixation has opened up new possibilities for the production of ammonia from water and air under mild conditions, but this process is confronted by the inherent challenges associated with theoretical and experimental works, limiting the efficiency of the nitrogen reduction reaction. Herein, we report for the first time a novel and efficient photoelectrocatalytic system, which has been prepared by assembling plasmonic Au nanoparticles with Fe-doped WO nanorods (denoted as WOF-Au). (i) The introduction of exotic Fe atoms into nonstoichiometric WO can eliminate bulk defects of the WO host, which resulted in narrowing bandgap energy and facilitating electron-hole separation and transportation. (ii) Meanwhile, Au nanoparticles combined with a semiconductor induce the localized surface plasmon resonance and generate energetic (hot) electrons, increasing electron density on WO nanorods. Consequently, this plasmonic WOF-Au system shows an NH production yield of 9.82 μg h cm at -0.65 V versus Ag/AgCl, which is ∼2.5-folds higher than that of the WOF (without Au loading), as well as very high stability, and no NH formation was found for the bare WO (WO). This high activity can be associated with the synergistic effects between the Fe dopant and plasmonic Au NPs on the host semiconductor WO. This work can bring some insights into the target-directed design of efficient plasmonic hybrid systems for N fixation and artificial photocatalysis.
光电化学（PEC）固氮为在温和条件下从水和空气中生产氨开辟了新的可能性，但该过程面临着与理论和实验工作相关的固有挑战，限制了氮还原反应的效率。在此，我们首次报道了一种新型高效的光电催化体系，它是通过将等离子体金纳米颗粒与铁掺杂的WO纳米棒组装而成（表示为WOF-Au）。（i）将外来的铁原子引入非化学计量比的WO中可以消除WO主体的体缺陷，这导致带隙能量变窄并促进电子-空穴的分离和传输。（ii）同时，金纳米颗粒与半导体结合会诱导局部表面等离子体共振并产生高能（热）电子，增加WO纳米棒上的电子密度。因此，这种等离子体WOF-Au体系在相对于Ag/AgCl为-0.65 V时显示出9.82 μg h cm的NH产量，这比WOF（未负载金）高出约2.5倍，并且具有非常高的稳定性，而裸WO（WO）未发现有NH生成。这种高活性可能与主体半导体WO上的铁掺杂剂和等离子体金纳米颗粒之间的协同效应有关。这项工作可为用于固氮和人工光催化的高效等离子体混合体系的目标导向设计带来一些启示。
