One of the excellent clean-energy source is hydrogen that can be produced from solar-driven water-splitting devices. Developing novel suitable catalyst that can efficiently catalyze significant electrochemical processes such as hydrogen evolution reaction (HER) and oxygen evolution reaction (OER), is one of the biggest challenges in developing new energy conversion technologies for water-splitting devices. In addition of water-splitting catalyst, oxygen reduction reactions (ORR) is another important electrochemical reaction that needs novel efficient electrocatalyst for clean energy. Therefore, the development of inexpensive and efficient devices will not only address the energy sustainability, but also, address the climate-change challenges. There are several key issues related to the existing electrocatalysts such as their high-cost and low electrochemical stability, which is limiting their large-scale applications in relevant clean energy technologies. Therefore, the development of novel electrocatalysts with high catalytic activity, long durability and low-cost will significantly facilitate the awareness of sustainable energy. Here, we will discuss the development of highly-porous, hybrid structures of low-dimensional hybrid nanomaterials as efficient electrocatalysts including theoretical calculations that discloses the enhanced electrocatalytic properties of these hybrid structures creating intrinsic chemical and electronic coupling.