Carbon-Based Nanoarchitectures of Various Dimensions for Water Splitting and Hydrogen Evolution: A Critical Review

Producing clean hydrogen fuel in quantities sufficient to meet the energy needs most reliant on fossil fuels is a critical step toward transitioning to net-zero emissions. Upscaling hydrogen production is closely linked to improving the stability, efficiency, and reliability of water splitting technologies. Nanoscale material platforms, engineered to maximize surface area and integrate complex surface chemistry, can significantly enhance the rate of hydrogen production in systems used in electrochemistry, catalysis, and materials science, driving innovations in energy storage and conversion technologies. However, with the rapid emergence of increasingly complex material architectures, selecting the most effective design for water splitting and hydrogen evolution systems remains a challenge. This article explores whether the shape and dimension of carbon-based nanoarchitectures are key factors in the rational design of materials for these applications. We examine how different structural forms, ranging from zero-dimensional quantum dots to one-, two-, and three-dimensional architectures, affect water splitting and hydrogen evolution mechanisms. Focusing on the latest advancements in carbon-based metamaterials and hierarchical nanoarchitectures, we evaluate their potential impact and highlight the challenges involved. We also summarize the current state of knowledge and discuss future directions for the development of carbon-based nanoarchitectures that could provide breakthroughs in hydrogen production.