Bi metal deposited hexagonal BiPO₄ with the exposure of {102} facet (Bi-HBPO-102) and Bi metal deposited monoclinic BiPO₄ with the exposure of {120} facet (Bi-MBPO-120) were prepared by chemical deposition method and solvothermal approach, respectively. The as-prepared catalysts presented more efficient photocatalytic activity of NO_x removal than pure BiPO₄ (2.0% for BiPO₄, 51.4% for Bi-HBPO-102 and 36.2% for Bi-MBPO-120) under visible light irradiation, which can be attributed to the synergistic effects endowed by the phosphate defect, the surface plasmon resonance (SPR) effect of Bi metal and the facet effect. The existence of phosphate defect was confirmed by the XPS and solid state EPR technique. The DFT calculation revealed the position of phosphate and the phosphate defect induced the formation of an intermediate level within the forbidden band to allow efficient charge transfer from valence band to conduction band. Moreover, the Bi metal would act as the electron contributor and electron conductor which facilitated the charge carriers separation. Therefore, a new charge transfer pathway can be certified on account of the fact that the covalent loop was evidently generated both at the interface and along with the path of [Bi₂O₂]²⁺ → Bi metal → PO₄³⁻ on the [email protected]₄. More importantly, the Bi-HBPO-102 with exposure of {102} facet exhibited higher photocatalytic activity than the Bi-MBPO-120 with exposed {120} facet. The {102} facet with the stronger distorted PO₄ tetrahedron and the lower potential energy barrier (-17.5eV) contributed to the contacted interface with the more efficient charge transfer, which promoted the generation of active radicals on {102} facet. Additionally, for Bi-HBPO-102, the reaction intermediate NO⁺ can be observed with in situ DRIFTS, which facilitated the activation of NO via the formation of NO⁺ to promote the oxidation of NO into final products. Herein, a new strategy for tailoring the charge transfer pathway was developed to enhance the photocatalytic performance and a new photocatalytic reaction mechanism for photocatalytic NO_x removal was proposed. This work could provide new insights into the modification of photocatalysts and mechanistic understanding of the gas-phase photocatalytic reaction mechanism.

通过化学沉积法制备了{102}面暴露的Bi金属沉积的六角形BiPO ₄（Bi-HBPO-102）和{120}面暴露的Bi金属沉积的单斜BiPO ₄（Bi-MBPO-120），并通过化学沉积法制备。溶剂热法。所制备的催化剂呈现更高效的光催化活性的NO _X去除比纯BIPO ₄为BIPO（2.0％₄，在可见光照射下，Bi-HBPO-102的含量为51.4％，Bi-MBPO-120的含量为36.2％），这可以归因于磷酸盐缺陷赋予的协同效应，Bi金属的表面等离振子共振（SPR）效应和方面效果。通过XPS和固态EPR技术确认了磷酸盐缺陷的存在。DFT计算揭示了磷酸盐的位置，磷酸盐缺陷诱导了禁带内中间能级的形成，从而允许电荷从价带到导带的有效转移。而且，Bi金属将充当促进电荷载流子分离的电子贡献者和电子导体。所以，₂ O ₂ ] ₂ ⁺ →Bi金属→PO ₄ ³⁻ [受电子邮件保护] ₄。更重要的是，暴露于{102}刻面的Bi-HBPO-102比暴露于{120}刻面的Bi-MBPO-120表现出更高的光催化活性。具有更强扭曲的PO ₄四面体和较低的势能垒（-17.5eV）的{102}面有助于更有效的电荷转移，从而促进了接触界面的形成，从而促进了{102}面上的活性基团的生成。此外，对于Bi-HBPO-102，可以通过原位DRIFTS观察到反应中间体NO ⁺，它通过形成NO ⁺促进了NO的活化。促进NO氧化成最终产物。在此，开发了一种用于调整电荷转移途径的新策略以增强光催化性能，并提出了一种用于光催化去除NO _x的新的光催化反应机理。这项工作可以为光催化剂的改性和气相光催化反应机理的机理研究提供新的见解。