Abstract Pt@Bi-TiO2 photocatalysts with different Bi (0–5 wt%) and Pt (0–2 wt%) contents were prepared by a two-step sol-gel and photo-deposition technique and were used in photo-reduction of CO2. The synthesized catalysts were characterized by X-ray powder diffraction (XRD), UV–Vis diffuse reflectance spectroscopy (DRS), scanning and transmission electron microscopy (SEM and TEM), nitrogen sorption measurement (BET), Raman spectroscopy, Electron paramagnetic resonance (EPR) spectroscopy and photoluminescence spectroscopy (PL). CO2 photo-reduction results revealed that the introduction of Bi into TiO2 structure and subsequent loading of Pt on its surface significantly increased the methane yield. Modified TiO2 with 3 wt% of Bi and 1.5 wt% of Pt resulted in the highest methane yield (20.6 μmol/g) that was about 6.2 times greater than pure TiO2. Enhanced CO2 adsorption on Bi-containing phases along with efficient charge separation caused by Pt nanoparticles was responsible for the superior activity in converting CO2 into methane.

中文翻译：

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Pt纳米粒子装饰Bi掺杂的TiO2作为CO2光还原成CH4的有效光催化剂

摘要 通过两步溶胶-凝胶和光沉积技术制备了具有不同 Bi (0-5 wt%) 和 Pt (0-2 wt%) 含量的 Pt@Bi-TiO2 光催化剂，并将其用于光还原二氧化碳。合成的催化剂通过 X 射线粉末衍射 (XRD)、紫外-可见漫反射光谱 (DRS)、扫描和透射电子显微镜 (SEM 和 TEM)、氮吸附测量 (BET)、拉曼光谱、电子顺磁共振 ( EPR）光谱和光致发光光谱（PL）。CO2 光还原结果表明，将 Bi 引入 TiO2 结构并随后在其表面负载 Pt 显着提高了甲烷产率。含有 3 wt% Bi 和 1.5 wt% Pt 的改性 TiO2 产生的甲烷产量最高（20.6 μmol/g），比纯 TiO2 高约 6.2 倍。