The layered potassium niobate, KNb₃O₈, is evident as a photocatalyst for hydrogen production from water splitting under UV light. We hereby reported a new modified sol–gel method for the preparation of potassium niobate photocatalyst. Photocatalytic water splitting has been improved in this work by loading Pt nanoparticles as cocatalyst. The catalysts were characterized by powder X-ray diffraction (XRD), Ultraviolet–Visible spectroscopy (UV–Vis), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). Their photocatalytic activities were in (i) an aqueous MeOH, used as sacrificial hole scavengers for hydrogen production and (ii) a new Z-scheme photocatalytic water splitting system where Pt/KNb₃O₈ was used for H₂ evolution and Pt/WO₃ was used for O₂ evolution. The I⁻/IO₃⁻ aqueous solution was used as redox couple for the photocatalytic Z-scheme over all water splitting under UV light irradiation. The photocatalysts were prepared by loading platinum on sol–gel synthesis KNb₃O₈ and commercial WO₃ via impregnation method. We find that, this KNb₃O₈ belonging to a orthorhombic structure with rod-like morphology. The Pt nanoparticles were sufficiently well-dispersed on the surface of photocatalyst, and enhanced photocatalytic properties. Our results show that I⁻ concentration significantly influenced the photocatalytic activity. The combination of Pt/KNb₃O₈ with Pt/WO₃ achieves a high H₂ evolution rate (539 μmol g⁻¹ h⁻¹) and O₂ evolution rate (140 μmol g⁻¹ h⁻¹) in 2 mM NaI solution.

层状铌酸钾KNb ₃ O ₈显然是从紫外线下水分解产生氢气的光催化剂。我们在此报告了一种新的改进的溶胶-凝胶法，用于制备铌酸钾光催化剂。通过负载Pt纳米颗粒作为助催化剂，光催化水分解得到了改善。催化剂的特征在于粉末X射线衍射（XRD），紫外-可见光谱（UV-Vis），扫描电子显微镜（SEM）和透射电子显微镜（TEM）。它们的光催化活性是在（i）用作水的牺牲空穴清除剂的MeOH水溶液中和（ii）在其中Pt / KNb ₃ O ₈的新型Z型光催化水分解系统中H ₂用于析出H ₂，Pt / WO ₃用于析出O ₂。的I ^- / IO ₃ ^-水溶液被用作氧化还原对用于在UV光照射下所有的水分解光催化Z-方案。通过浸渍法将铂负载在溶胶-凝胶合成KNb ₃ O ₈和商业WO ₃上制备光催化剂。我们发现，该KNb ₃ O ₈属于具有棒状形态的正交结构。Pt纳米粒子在光催化剂表面充分分散，增强了光催化性能。我们的结果表明我⁻浓度显着影响光催化活性。的Pt /的KNB组合₃ ö ₈有Pt / WO _3个实现了高ħ ₂进化率（539微摩尔克^-1  ħ ^-1）和O ₂释放速率（140微摩尔克^-1  ħ ^-1在2mM的NAI）解。