Hydrogen is an excellent environmentally-friendly fuel that can be produced from solar-driven water-splitting devices. One of the biggest challenges in developing new energy conversion technologies for water-splitting devices is to find suitable and durable catalysts that can efficiently catalyze the key electrochemical processes, i.e., the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER), In addition of water-splitting catalyst, the other important reaction that needs novel efficient catalyst for clean energy is oxygen reduction reactions (ORR). Therefore, the development of inexpensive and efficient devices will not only address the energy problem but also, address climate-change challenges. Issues related to existing electrocatalysts include their high-cost and low electrochemical stability, limiting their large-scale applications in relevant clean energy technologies. To this regard, the development of novel electrocatalysts exhibiting high catalytic activity, long durability, as well as low-cost will greatly facilitate the realization of environmentally-friendly energy. Here, we will discuss the development of highly-porous, hybrid structures of one-dimensional (1D) and two-dimensional (2D) layered materials as efficient water-splitting electrocatalysts including density functional theory calculations, which reveals the enhanced electrocatalytic properties of these hybrid structures creating intrinsic chemical and electronic coupling.