3D Hierarchical Carbon-Rich Micro-/Nanomaterials for Energy Storage and Catalysis

Increasing concerns over climate change and energy shortage have driven the development of clean energy devices such as batteries, supercapacitors, fuel cells and solar water splitting in the past decades. And among potential device materials, 3D hierarchical carbon-rich micro-/nanomaterials (3D HCMNs) have come under intense scrutiny because they can prevent the stacking and bundling of low-dimensional building blocks to not only shorten diffusion distances for matter and charge to achieve high-energy-high-power storage but also greatly expose active sites to achieve highly active, durable and efficient catalysis. Based on this, this review will summarize the synthetic strategies and formation mechanisms of 3D HCMNs, including 3D nanocarbons, polymers, COFs/MOFs, templated carbons and derived carbon-based hybrids with a focus on 3D superstructures such as urchins, flowers, hierarchical tubular structures as well as nanoarrays including nanotube, nanofiber and nanosheet arrays. This review will also discuss the application of 3D HCMNs in energy storage and catalysis systems, including batteries, supercapacitors, electrocatalysis and photo(electro)catalysis. Overall, this review will provide a comprehensive overview of the recent progress of 3D HCMNs in terms of preparation strategies, formation mechanisms, structural diversities and electrochemical applications to provide a guideline for the rational design and structure–function exploration of 3D hierarchical nanomaterials from different sources beyond carbon-based species.