Jung Hayoon, Cha Gihoon, Kim Hyesung, Will Johannes, Zhou Xin, Bad'ura Zdeněk, Zoppellaro Giorgio, Dobrota Ana S, Skorodumova Natalia V, Pašti Igor A, Sarma Bidyut Bikash, Schmidt Jochen, Spiecker Erdmann, Breu Josef, Schmuki Patrik
Department of Materials Science and Engineering, WW4-LKO, Friedrich-Alexander-Universität Erlangen-Nürnberg, Martensstraße 7, 91058, Erlangen, Germany.
Regional Centre of Advanced Technologies and Materials, Czech Advanced Technology and Research Institute (CATRIN), Palacký University, Šlechtitelů 27, Olomouc, 78371, Czech Republic.
Small. 2025 Jul;21(29):e2502428. doi: 10.1002/smll.202502428. Epub 2025 Jun 2.
The stabilization of single-atom catalysts on semiconductor substrates is pivotal for advancing photocatalysis. TiO, a widely employed photocatalyst, typically stabilizes single atoms at oxygen vacancies-sites that are accessible but prone to agglomeration under illumination. Here, we demonstrate that cation vacancies in Ti-deficient TiO nanosheets provide highly stable anchoring sites for Pt single atoms, enabling persistent photocatalytic hydrogen evolution. Ultrathin TiO nanosheets with intrinsic Ti vacancies are synthesized via lepidocrocite-type titanate delamination and Pt single atoms are selectively trapped within these vacancies through a simple immersion process. The resulting Pt-decorated nanosheets exhibit superior photocatalytic hydrogen evolution performance, outperforming both Pt nanoparticle-loaded nanosheets and benchmarked Pt single-atom catalysts on P25. Crucially, Pt atoms anchored at Ti vacancies display remarkable resistance to light-induced agglomeration, a key limitation of conventional single-atom photocatalysts. Density functional theory calculations reveal that Pt incorporation into Ti vacancies is highly thermodynamically favorable and optimizes hydrogen adsorption energetics for enhanced catalytic activity. This work highlights the critical role of cation defect engineering in stabilizing single-atom co-catalysts and advancing the efficiency and durability of photocatalytic hydrogen evolution.
单原子催化剂在半导体基底上的稳定化对于推动光催化至关重要。二氧化钛（TiO）作为一种广泛应用的光催化剂，通常将单原子稳定在氧空位处——这些位点易于接近，但在光照下容易团聚。在此，我们证明了缺钛TiO纳米片中的阳离子空位为Pt单原子提供了高度稳定的锚定位点，从而实现持续的光催化析氢。通过纤铁矿型钛酸盐剥离合成具有固有Ti空位的超薄TiO纳米片，并通过简单的浸渍过程将Pt单原子选择性地捕获在这些空位中。所得的Pt修饰纳米片表现出优异的光催化析氢性能，优于负载Pt纳米颗粒的纳米片以及P25上的基准Pt单原子催化剂。至关重要的是，锚定在Ti空位处的Pt原子对光诱导团聚表现出显著的抗性，这是传统单原子光催化剂的一个关键限制。密度泛函理论计算表明，Pt掺入Ti空位在热力学上非常有利，并优化了氢吸附能以提高催化活性。这项工作突出了阳离子缺陷工程在稳定单原子助催化剂以及提高光催化析氢效率和耐久性方面的关键作用。
