Boron-based two-dimensional materials are of interest for use in electronic devices and catalytic applications, for which it is important that they are chemically stable. Here, we explore the chemical stability of hydrogen boride nanosheets in water. Experiments reveal that mixing hydrogen boride and water produces negligible amounts of hydrogen, suggesting that hydrolysis does not occur and that hydrogen boride is stable in water, which is in contrast to most boron hydride materials. First-principles calculations reveal that the sheets interact weakly with water even in the presence of defects and that negatively charged boron prevents the onset of hydrolysis. We conclude that the charge state of boron and the covalent boron-boron bond network are responsible for the chemical and structural stability. On the other hand, we found that proton exchange with hydrogen boride nanosheets does occur in water, indicating that they become acidic in the presence of water.

硼基二维材料在电子设备和催化应用中很受关注，因此它们的化学稳定性很重要。在这里，我们探索了硼化氢纳米片在水中的化学稳定性。实验表明，将硼化氢和水混合产生的氢量可忽略不计，这表明不会发生水解并且硼化氢在水中是稳定的，这与大多数氢化硼材料相反。第一性原理计算表明，即使存在缺陷，薄片与水的相互作用也很弱，并且带负电荷的硼可防止水解的发生。我们得出结论，硼的电荷状态和共价硼 - 硼键网络是化学和结构稳定性的原因。另一方面，