Electrocatalytic water splitting has been regarded as a promising technology for the production of ultrapure hydrogen (H2) in this decade. Nonetheless, the efficiency of the water splitting is severely hampered by sluggish anodic oxygen evolution reaction (OER). The coupling of thermodynamically favourable anodic oxidation reactions (small molecule oxidations) is an innovative strategy to overcome these critical challenges in the conventional technology. Herein, we demonstrated the use of liquid phase exfoliated 2D exfoliated boron nanosheets (eBNS) as an efficient non-noble electrocatalyst for traditional/hybrid water electrolyzer. The physico-chemical studies revealed that the exfoliation of boron sheets leads to decrease in lateral size and layer numbers, increase in surface area, without affecting their crystallinity. Benefitting from the increased surface and edge interfaces, the eBNS showed enhanced electrocatalytic activity towards hydrogen evolution reaction (HER) (146 mV), OER (291 mV) and methanol oxidation reactions (MOR) (190 mV) to meet 10 mA cm-2 those are better than the bulk boron. The eBNS/NF-4 hybrid electrolyzer (HER+MOR) requires 1.55 V (@ 10 mA cm-2) to electrosynthesis value added formate and hydrogen with 160 mV lesser voltage compared to conventional electrolyzer (HER+OER). Furthermore, the real time hybrid water electrolyzer (in H-type cell) delivers superior H2 production with 93 % faradaic efficiency. Overall, this work demonstrates the use of non-noble 2D eBNS as a potential candidate for next generation energy-efficient green H2 production systems.