Abstract Photocatalytic water splitting has increasingly attracted attention as one of the most useful methods of converting solar energy into chemical fuel. However, the undesirable reverse reaction significantly limits the enhancement of efficiency. Herein, we fabricated an Au nanorods/TiO2 nanodumbbells structure photocatalyst (Au NRs/TiO2 NDs) via a facile synthetic strategy, which has spatially separated oxidation and reduction reaction zones. Owing to the unique structure, the charge separation of these photocatalysts can be significantly improved and the reverse reaction can be efficiently inhibited. The photogenerated electrons were injected from the TiO2 to the Au NRs, and a positively charged TiO2 region and negatively charged Au region were formed under UV irradiation. An enhanced hydrogen production performance was obtained compared with that seen in normal Au-TiO2 heterostructure. Under optimized conditions, the H2-production rate can reach up to 60,264 μmol/g/h, about six times higher than previously reported Au/TiO2 photocatalysts. Besides this, our work also demonstrates the key factors of precise synthesis of the Au NRs/TiO2 NDs structure, which provides a new perspective and experience for the design of similar catalysts.

中文翻译：

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具有空间氧化还原区的Au-TiO2纳米哑铃光催化剂的可控合成

摘要 光催化分解水作为将太阳能转化为化学燃料最有用的方法之一越来越受到关注。然而，不希望的逆反应显着限制了效率的提高。在此，我们通过简单的合成策略制备了 Au 纳米棒/TiO2 纳米哑铃结构的光催化剂（Au NRs/TiO2 NDs），其具有空间分离的氧化和还原反应区。由于其独特的结构，这些光催化剂的电荷分离可以得到显着改善，并且可以有效地抑制逆反应。光生电子从 TiO2 注入到 Au NRs，在紫外线照射下形成带正电的 TiO2 区域和带负电的 Au 区域。与在正常 Au-TiO2 异质结构中看到的相比，获得了增强的制氢性能。在优化条件下，产氢速率可达 60,264 μmol/g/h，比之前报道的 Au/TiO2 光催化剂高约 6 倍。除此之外，我们的工作还展示了精确合成Au NRs/TiO2 NDs结构的关键因素，为类似催化剂的设计提供了新的视角和经验。