Biodiversity endows similar species with subtle differences in composition, microstructure, and surface chemistry, making biomass a promising precursor to control the resulting active structure for heterocatalysis. Here, it is shown that Tremella fuciformis (Tfu), possessing an abundant porous structure and favorable metal affinity, is favorably serves as a precursor for confining uniform metal nanoparticles, by comparing the chemical characteristics of six varieties of agarics. The modest size of Co in the Tfu derived composite, Co@NPC‐Tfu (NPC = N, P co‐doped carbon), is suitable for in situ semi‐oxidation during oxygen evolution reaction (OER), forming a stable core‐shell structure of Co3O4@Co. Thus, Co@NPC‐Tfu can be used as a state‐of‐the‐art electrocatalyst for OER with an overpotential of 213.6 ± 4.1 mV at 10 mA cm−2, and a significant turnover frequency of 3.21 s−1 at 300 mV, benefitting from the optimum trade‐off between the atom utilization and electrical conductivity. Operando spectroscopy and theoretical calculations unveil the occupied state modulation of the robust carbon‐bonded POx groups, which optimizes the intermediate adsorption to accelerate OER kinetics. Moreover, Tfu derived Ni@NPC‐Tfu can be also prepared as a high‐performance hydrogen evolution reaction electrocatalyst, which can be utilized for efficient overall water splitting coupled with Co@NPC‐Tfu.

Electrocatalytic water splitting powered by sustainable electricity is a crucial approach for the development of new generation green hydrogen technology. Biomass materials are abundant and renewable, and the application of catalysis can increase the value of some biomass waste and turn waste into fortune. Converting economical and resource‐rich biomass into carbon‐based multicomponent integrated catalysts (MICs) has been considered as one of the most promising ways to obtain inexpensive, renewable and sustainable electrocatalysts in recent years. In this review, recent advances in biomass‐derived carbon‐based MICs towards electrocatalytic water splitting are summarized, and the existing issues and key aspects in the development of these electrocatalysts are also discussed and prospected. The application of biomass‐derived carbon‐based materials will bring some new opportunities in the fields of energy, environment, and catalysis, as well as promote the commercialization of new nanocatalysts in the near future.