Electrochemical water splitting is one of the most efficient techniques to produce hydrogen, which provides clean and sustainable energy. Developing an efficient catalyst for hydrogen evolution reaction (HER) based on 2D molybdenum disulfide is challenging because MoS₂ layers' restacking leads to insufficient access to active sites. In this study, the drawbacks of 1T MoS₂ catalyst were overcome by employing carbon nano-onion (CNO) and combining it with other metal oxides. The unique CNO-MoS₂ heterostructure formed by growing a few-layered 2D 1T MoS₂ on the CNO core facilitates easy charge transfer through heterojunction formation. MoS₂ combined with BiVo₄ also showed another possibility for a high rate of hydrogen production. These heterostructures mitigate restacking and maintain structural stability, providing a long-term high-performance catalyst. CNO-MoS₂ exhibited an excellent HER performance with an overpotential of 53 mV vs. RHE and Tafel slope of 40.8 mV dec-1 for over 25 h, showing it one of the best HER catalysts next to platinum. BiVo4/MoS₂ photoanode also showed excellent performance. These studies highlight a new highly stable, highly performing non-noble metal catalyst for electrochemical water splitting applications.