We explored the superconductivity in oxygen-hydrogen binary system, H h O1-h , under high-pressure by an evolutionary algorithm-based materials informatics approach. We searched for metallic and superconducting phases in pressures up to 300 GPa using a crystal structure prediction technique based on a genetic algorithm and first-principles calculations and found that hydrogen superoxide (HO2) with an orthorhombic Pnnm, which emerges as a metastable compound in pressure above 180 GPa, is the only compound showing the superconductivity. The superconducting critical temperature T c is 9.78 K at 200 GPa, which is higher than that of pure solid oxygen, 2.87 K, due to the effect of the hydrogenation. We confirmed that the T c value shows a good agreement with potential superconducting critical temperature T c pot estimated by the superconductivity predictor, which we have previously developed by a genetic programming using 497 first-principles datasets of other binary hydrides. Moreover, supposing that all the H h O1-h compounds are superconductors at pressures in 150--200 GPa, we investigated the potential superconductivity of the H h O1-h system using the predictor and obtained that T c pot shows 10 K for h = 0.0333 and increases to 100 K with the increase of h to 0.9667.

中文翻译：

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高压下超氧化氢的超导性

我们通过基于进化算法的材料信息学方法探索了高压下氧氢二元系统 H h O1-h 的超导性。我们使用基于遗传算法和第一性原理计算的晶体结构预测技术在高达 300 GPa 的压力下搜索金属和超导相，发现具有正交 Pnnm 的超氧化氢 (HO2) 在压力下作为亚稳态化合物出现180 GPa 以上，是唯一表现出超导性的化合物。由于氢化作用，超导临界温度T c 在200 GPa时为9.78 K，高于纯固体氧的2.87 K。我们确认 T c 值与超导预测器估计的潜在超导临界温度 T c pot 非常吻合，我们之前使用其他二元氢化物的 497 个第一性原理数据集通过遗传编程开发了该预测器。此外，假设所有 H h O1-h 化合物在 150--200 GPa 的压力下都是超导体，我们使用预测器研究了 H h O1-h 系统的潜在超导性，并获得了 T c pot 显示 10 K for h = 0.0333 并随着 h 增加到 0.9667 增加到 100 K。