Although one-step-excitation overall water splitting on a particulate photocatalyst is a simple means of performing scalable solar-to-hydrogen energy conversion, there is a lack of photocatalysts with significant activity under visible light. Despite its superior visible-light absorption, the Ta₃N₅ photocatalyst has not accomplished overall water splitting due to strong charge recombination at defects. Here, we show rapid growth of Ta₃N₅ nanorods on lattice-matched cubic KTaO₃ particles through the volatilization of potassium species during a brief nitridation process. The Ta₃N₅ nanorods generated selectively on the edge of KTaO₃ are spatially separated and well-defined single crystals free from grain boundaries. When combined with the Rh/Cr₂O₃ co-catalyst, the single-crystal Ta₃N₅ nanorods split water into hydrogen and oxygen very efficiently under visible light and simulated sunlight. Our findings demonstrate the importance of nanostructured single-crystal photocatalysts free from structural defects in solar water splitting.

尽管在颗粒状光催化剂上进行一步激发的总水分解是执行可扩展的太阳能到氢能转化的简单方法，但仍缺乏在可见光下具有显着活性的光催化剂。尽管Ta ₃ N ₅光催化剂具有优异的可见光吸收能力，但由于缺陷处的强电荷复合，因此并未实现总的水分解。在这里，我们显示了通过短暂的氮化过程中钾物种的挥发，晶格匹配立方KTaO ₃颗粒上Ta ₃ N ₅纳米棒的快速生长。在KTaO ₃边缘选择性产生的Ta ₃ N ₅纳米棒在空间上是分开的且定义明确的单晶，没有晶界。当与Rh / Cr ₂ O ₃助催化剂结合使用时，单晶Ta ₃ N ₅纳米棒在可见光和模拟阳光下非常有效地将水分解为氢和氧。我们的发现证明了在太阳能水分解中没有结构缺陷的纳米结构单晶光催化剂的重要性。