The environment and energy crisis due to carbon dioxide emissions from burning fossil fuels have increased the urgency to explore sustainable energy, while hydrogen with high energy density and environmental friendliness represents a promising solution. Currently, hydrogen production from renewable-energy-driven water splitting via electrocatalytic, photocatalytic, and photoelectrochemical processes are actively investigated, where the design of stable and active earth-abundant catalysts is one of the most important scientific questions. Among the numerous metal oxide catalysts, tantalum pentoxide (Ta₂O₅) has recently received great attention due to its suitable band gap and high stability as an anode for water splitting. In this Review, we start with a summary of diverse Ta₂O₅ phases with different crystalline structures. We also summarize the experimental methods for the synthesis of different Ta₂O₅ phases, followed by discussions of the electronic structures of each phase from theoretical calculations. Then, we review the recent applications of Ta₂O₅ as the anode catalyst for the oxygen evolution reaction (OER) and the cathode catalyst for hydrogen evolution reaction (HER). Finally, we discuss the challenges and opportunities of using Ta₂O₅-based materials as viable catalysts for water splitting, with an emphasis on the crucial role of the synergistic effort from both theory and experiment.

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五氧化二钽：从晶体结构到水分解应用

燃烧化石燃料产生的二氧化碳排放造成的环境和能源危机增加了探索可持续能源的紧迫性，而具有高能量密度和环境友好性的氢是一种有前途的解决方案。目前，通过电催化、光催化和光电化学过程从可再生能源驱动的水分解制氢的研究正在积极研究，其中稳定且活性丰富的催化剂的设计是最重要的科学问题之一。在众多的金属氧化物催化剂中，五氧化二钽（Ta ₂ O ₅）由于其合适的带隙和作为水分解阳极的高稳定性而最近受到了极大的关注。在这篇评论中，我们首先总结了各种 Ta具有不同晶体结构的₂ O _{5相。我们还总结了不同Ta 2} O ₅相合成的实验方法，然后从理论计算中讨论了各相的电子结构。_{然后，我们回顾了Ta 2} O ₅作为析氧反应（OER）阳极催化剂和析氢反应（HER）阴极催化剂的最新应用。_{最后，我们讨论了使用 Ta 2} O ₅基材料作为可行的水分解催化剂的挑战和机遇，重点是理论和实验协同努力的关键作用。