Integration of triboelectric nanogenerators (TENGs) with water splitting offers a promising approach for generating green hydrogen from mechanical energy. However, the development of efficient TENGs is challenged by significant triboelectric losses. To enhance sustainable energy harvesting, it is crucial to minimize these losses and improve tribo-polarities. Recent advancements in incorporating conductive fillers have proven effective in improving triboelectric performance. In this study, a new class of bifunctional amino surface-modified graphene oxide (MGO) fillers synthesized from graphite powder is introduced. The MGO filler enhances the positive polarity of the polymer through amino groups while reducing triboelectric loss due to the inherent conductivity of graphene. Incorporating 1.5 wt.% of MGO into silk electrospun membranes (1.5SMGO) boosted the surface positivity from +695 to +1905 V, surpassing unmodified graphene oxide (GO) (+1220 V), highlighting the impact of surface modification. The resulting TENG with 1.5SMGO exhibits an open circuit voltage of 1135 V and a current density of 11.76 mA m−2, demonstrating its effectiveness as a sustainable energy harvester for low-power electronics. Additionally, the proposed TENG can serve as an energy source for water-splitting, enabling green hydrogen production. Thus, the bifunctional MGO-based TENG holds significant potential for self-powered wearable electronics and water-splitting applications.