Synthesis of Sustainable Lignin Precursors for Hierarchical Porous Carbons and Their Efficient Performance in Energy Storage Applications

Abstract

Lignin-derived porous carbons have great potential for energy storage applications. However, their traditional synthesis requires highly corrosive activating agents in order to produce porous structures. In this work, an environmentally friendly and unique method has been developed for preparing lignin-based 3D spherical porous carbons (LSPCs). Dropwise injection of a lignin solution containing PVA sacrificial templates into liquid nitrogen produces tiny spheres that are lyophilized and carbonized to produce LSPCs. Most of the synthesized samples possess excellent specific surface areas (426.6–790.5 m2/g) along with hierarchical micro- and mesoporous morphologies. When tested in supercapacitor applications, LSPC-28 demonstrates a superior specific capacitance of 102.3 F/g at 0.5 A/g, excellent rate capability with 70.3% capacitance retention at 20 A/g, and a commendable energy density of 2.1 Wh/kg at 250 W/kg. These materials (LSPC-46) also show promising performance as an anode material in sodium-ion batteries with high reversible capacity (110 mAh g–1 at 100 mA g–1), high Coulombic efficiency, and excellent cycling stability. This novel and green technique is anticipated to facilitate the scalability of lignin-based porous carbons and open a range of research opportunities for energy storage applications.

Multistage Porous Carbon Derived from Enzyme-Treated Waste Walnut Green Husk and Polyethylene Glycol for Phase Change Energy Storage

“…Therefore, the excellent properties of carbon materials make them an attractive candidate for SSPCM synthesis, and the application of porous carbon-based SSPCMs in buildings will reduce indoor temperature fluctuations, thus achieving energy savings [ 31 ]. This is especially due to the composition of the walnut green husk (high lignin–fiber content), which is a good precursor for the formation of micropores and mesopores during carbonization and activation to obtain a large pore volume and a high specific surface area [ 32 , 33 , 34 ]. However, bio-based carbon materials also face many problems, such as complex synthesis routes, the preparation process requiring a certain temperature and pressure, and the performance still needing to be improved [ 35 , 36 , 37 ].…”

Lignin-Derived Materials for Sustainable Development of Ionic Thermoelectric Supercapacitors

“…Waste heat induces ion movement across the hydrogel, creating a potential difference known as the Seebeck effect. This difference charges supercapacitor electrodes made of porous carbon, enabling swift energy storage [6,7].…”

Regulating the Porous Structure of Lignin-Derived Carbon Materials for High Adsorption Performance via Dual Nitrogen Source-Assisted Activation

“…Lignin, as a naturally renewable resource, has become an ideal precursor for carbon material preparation, attributed to its high carbon content, abundant raw material sources, and unique three-dimensional network structure. − Lignin-derived carbon materials not only boast low toxicity and excellent chemical stability but also exhibit high specific surface areas and controllable pore structure, showcasing significant potential in catalysis, energy storage, and environmental remediation. − To enhance the physicochemical properties and adsorption capabilities of carbon materials, chemical activation and heteroatom doping are commonly used for modification. , Chemical activation involves the use of agents such as KOH, NaOH, K 2 CO 3 , ZnCl 2 , and H 3 PO 4 , which effectively increase the specific surface area and pore structure of materials, thereby improving the diversity and quantities of surface functional groups. Consequently, this leads to an increased number of available binding sites, thereby augmenting the efficiency of adsorption .…”