Materials displaying metal-insulator transitions (MITs) as a function of external parameters such as temperature, pressure, or composition are most intriguing from the fundamental point of view and also hold high promise for applications. Vanadium dioxide (VO₂) is one of the most prominent examples of MIT having prospective applications ranging from intelligent coatings, infrared sensing, or imaging, to Mott memory and neuromorphic devices. The key aspects conditioning possible applications are the controllability and reversibility of the transition. Here we present an intriguing MIT in hydrogenated vanadium dioxide, H_xVO₂. The transition relies on an increase of the electron occupancy through hydrogenation on the transition metal vanadium, driving the system insulating by a hybrid of two distinct MIT mechanisms. The insulating phase observed in HVO₂ with a nominal d² electronic configuration contrasts with other rutile d² systems, most of which are metallic. Using spectroscopic tools and state-of-the-art many-body electronic structure calculations, our investigation reveals a correlation-enhanced Peierls and a Mott transition taking place in an orbital-selective manner cooperate to stabilize an insulating phase. The identification of the hybrid mechanism for MIT controlled by hydrogenation opens the way to radically design strategies for future correlated oxide devices by controlling phase reversibly while maintaining high crystallinity.

显示金属-绝缘体转变 (MIT) 作为外部参数（如温度、压力或成分）的函数的材料从基本角度来看是最有趣的，并且在应用方面也具有很高的前景。二氧化钒 (VO ₂ ) 是 MIT 最突出的例子之一，具有从智能涂层、红外传感或成像到 Mott 记忆和神经形态设备等领域的应用前景。调节可能应用的关键方面是过渡的可控性和可逆性。在这里，我们展示了一个有趣的 MIT 氢化二氧化钒 H _x VO ₂. 过渡依赖于通过过渡金属钒上的氢化增加电子占有率，通过两种不同的 MIT 机制的混合驱动系统绝缘。在具有标称d ^{2电子配置的 HVO} ₂中观察到的绝缘相与其他金红石d ²形成对比系统，其中大部分是金属的。使用光谱工具和最先进的多体电子结构计算，我们的研究揭示了相关性增强的 Peierls 和以轨道选择性方式发生的 Mott 跃迁协同稳定绝缘相。由氢化控制的 MIT 混合机制的鉴定为通过在保持高结晶度的同时可逆地控制相来彻底设计未来相关氧化物器件的策略开辟了道路。