Graphene Aerogel Research Articles

Interlayer growth of SiC nanowires in graphene aerogel for thermal conductivity enhancement of epoxy resin and its mechanism

AbstractThe chemical reduction method is a simple and popular way to contrast the graphene network to improve the polymer matrix's thermal conductivity. And hybrid thermal conductive fillers composed of two or more mixed fillers through chemical synthesis usually have better thermal conductivity because of the synergistic effort. In this work, silicon carbide nanowires (SiC NWs) in graphene aerogels are synthesized with the chemical vapor deposition method, acting as bridges for phonon transmission between adjacent graphene sheets. The RGO/SiC NWs aerogel‐endowed EP composites have a high thermal conductivity of 3.79 W/mK at a filler loading of 5.5 wt%, and 4.23 W/mK at a filler loading of 7.5 wt%, which is 1895% and 2126% higher than pure EP resin, respectively. Finite element analysis (FEA) is utilized to analyze the heat conduction mechanism of composites at last.

Binder-free ultrathin pellets of nanocomposites based on Fe3O4@nitrogen-doped reduced graphene oxide aerogel for electromagnetic interference shielding

The synergistic effects of a hybrid nanocomposite (Fe3O4@NrGO) and their influence on electromagnetic pollution shielding (EMI SE) were explored. This is a current concern where the impacts need to be fully clarified and assertively addressed. Thus, the main focus of the paper was based on the physical and mechanical properties of porosity, surface area, flexibility and, mainly, electrical conductivity of the graphene aerogels, which do not require the use of a binder and are of great interest for the EMI SE area. The precursors (rGO, NrGO and Fe3O4), as well as the nanocomposite, underwent thorough structural characterisation to understand their nature. Characteristic bands of C-N/C=N bonds and a content of 8.03 at% N were identified, with a high N:O ratio of 1.31, indicating efficient doping of the conductive matrix. The aerogel NrGO phase, with a quality of just 5 layers, and the Fe3O4 phase, with domains around 5 nm, were confirmed, as well as the superposition of the signals in the Fe3O4@NrGO pattern. Electron microscopy images and elemental map also demonstrated the efficient distribution of Fe3O4 in the matrix and its porous appearance. Thus, leveraging the advantages of aerogel, extremely light ultra-thin pellets measuring 0.1 mm and weighing 10 mg were produced. The high nitrogen doping of the graphene network, the presence of magnetic nanoparticles, as well as the high surface area and porosity achieved in the production of the nanocomposite, were responsible for high specific shielding effectiveness of 2730 dB · cm−1 at 10.7 GHz and an average in the X-band of 1590 dB · cm−1. Thus, the improved and synergistic mechanisms highlighted the promising advantages of using these highly porous doped materials, demonstrating that the Fe3O4@NrGO hybrid presents high value for investigations in the application of EMI SE.

Analysis of the characteristics and mass transfer mechanism of 3D-printed graphene aerogel composite electrode based on digital reconstruction technology

3D-printed graphene aerogel has attracted great attention in many fields, including energy storage, environmental protection and intelligent sensing areas. However, the study on the mass transfer performance of 3D-printed graphene aerogel is limited. This paper investigates the characteristics and mass transfer mechanism of 3D-printed graphene aerogel composite electrodes in vanadium redox flow battery (VRFB) based on digital reconstruction technology. Herein, the model of 3D-printed graphene aerogel composite electrode with realistic porous structure was digital reconstructed based on microcomputed tomography (μCT). Owing to the advantages of digital reconstruction, the mass transfer mechanism of vanadium ion in porous electrode can be revealed. The results show that the characteristic structure with large pores enhances the mass transfer performance of the 3D-printed graphene aerogel composite electrode and exhibits relatively high porosity, ion permeability and diffusivity. In the printed filament, the graphene sheets are arranged at a certain angle, and the electrolyte transfers along the direction of the graphene sheets. Furthermore, the proposed method based on digital reconstruction shows promising prospects for the optimal design of aerogel electrode for energy storage devices.

Capacitive deionization of uranium mediated by dioxygen functionalities in the C = O = C = O segment of polyacrylic acid-functionalized graphene aerogel

The extraction of uranium is crucial for sustaining a consistent nuclear fuel cycle, yet the task of isolating uranyl ions from aqueous solutions presents formidable challenges. Herein, a PAA/GO aerogel was developed using polyacrylic acid-functionalized graphene, wherein the C = O = C = O segment's dual oxygen served both as electrodes for capacitive deionization and as sites for charge transfer and uranyl capture, effectively purifying uranium mine wastewater. Furthermore, under the stringent experimental conditions set at 298 K and a pH of 5.5, the PAA/GO composite demonstrated an impressive adsorption capacity of 898.7 mg g−1. When this composite was further amalgamated into the CDI architecture, it exhibited an impressive 92 % uranium extraction from genuine mine effluent at an unwavering potential of 0.9 V. Through density functional theory (DFT) analyses, the adsorption energies of [UO2(H2O)5]2+ with the PAA/GO composite involving C = O = C = O ligands displayed the highest value compared with PAA and PAA/GO composite (involving monodentate and bidentate ligands). The Bader charge analysis further indicating the greatest charge loss in the uranium ion. In conclusion, the novel PAA/GO aerogel 3D framework with its specific C = O = C = O regional chain sets a pioneering standard in uranium extraction techniques, showcasing unprecedented efficiency in UO22+ removal from aqueous solutions.

3D Printed Carbon Framework with the Graphene Aerogel for Microbial Fuel Cell Application

There is a high interest in living organism-compatible materials associated with electrically active interfaces. Bacteria/electrode interfaces implement smart, functional systems with responses, based on which it is possible to elaborate self-regulating energy generation systems. Carbon materials have a number of advantages, such as biocompatibility, low electrical resistance, and the possibility of increasing the electrode surface on an industrial scale. The most promising approach for the industrial production of electrodes is 3D printing. We propose a 3D-printed carbon electrode – a novel lightweight material for electrodes in bioelectrochemical systems for efficient bioelectricity utilization.The pyrolytic process for manufacturing carbon electrodes is promising for upscaling and industrial applications. However, there is a problem of volume loss when 3D-printed polymers are pyrolyzed in an inert environment. We propose a new strategy for the thermal treatment of 3D-printed polymers that allow for reduced volume loss under pyrolytic carbonization. In addition, to achieve a higher electrode surface area, the graphene aerogel could be impregnated into the 3D-printed scaffolds. Chemical modification of graphene surface can enhance biocompatibility. Specifically, the oxidation of graphene leads to forming a hydrophilic and biocompatible material. We tune graphene hydrophilic properties and electrical conductivity via control over the thermal reduction of the oxidized form of graphene–graphene oxide1.Such sponge morphology affords 3D-printed carbon scaffolds an excellent lightweight host scaffold for microorganisms, in which the graphene nanowalls are homogeneously occupied by S. oneidensis MR-1. We demonstrate a novel sustainable method to produce graphene-based lightweight 3D printed electrode materials for green energy production from biomass. The proposed technology creates the opportunity for novel, innovative, disruptive graphene applications that can lead to the establishment of new energy-related industries and facilitate many startups in the ecosystem. Acknowledgments This work was supported by the Ministry of Education (Singapore) through the Research Centre of Excellence program (grant EDUN C-33-18-279-V12, I-FIM). References Xuanye Leng, Ricardo J. Vazquez, Samantha R. McCuskey, Glenn Quek, Yude Su, Konstantin G. Nikolaev, Mariana C.F. Costa, Siyu Chen, Musen Chen, Kou Yang, Jinpei Zhao, Mo Lin, Zhaolong Chen, Guillermo C. Bazan, Kostya S. Novoselov, Daria V. Andreeva, Carbon, 205, 2023, 33-39.

Multi-crosslinked robust alginate/polyethyleneimine modified graphene aerogel for efficient organic dye removal

Polymer composite aerogel holds great promise for sewage treatment. Here, a novel triply crosslinked alginate/graphene aerogel for efficient organic dye removal was reported. The triple crosslinking of aerogel was realized firstly by the association between in-situ released Ca2+ ions and sodium alginate (SA). And the electrostatic attraction between polyethyleneimine-modified reduced graphene oxide (PEI-RGO) and the alginate chain provides an additional boost to crosslinking the aerogel. Moreover, the hydrogen bonding between PEI and SA also helps in achieving the crosslinking of the aerogel. Thus, the robust triply crosslinked alginate/graphene aerogel was obtained with using cost-effective precursors and a straightforward process. Additionally, the as-prepared aerogels were employed to remove the cationic dyes from wastewater. It was found that the porous alginate/graphene exhibited a strong affinity to methylene blue (MB) and neutral red (NR). The adsorption process of the aerogel towards MB was in accordance with the Langmuir isothermal model and pseudo-second-order model, and the maximum theoretical adsorption capacities were 1091.9 and 813.2 mg g−1, suggesting its potential application in sewage treatment.

Structural Formation and Pore Control of Freeze-Cast Directional Graphene Aerogel (DGA).

Directional graphene aerogels (DGAs) are proposed as electrode materials to alleviate ionic and mass transport issues in organic redox flow batteries (ORFBs). DGAs with high pore directionality would provide low resistance channels for effective ionic charge and liquid electrolyte transport in these devices. DGAs' porous and directional characteristics can be controlled by the growth of ice crystals during freeze casting, which is influenced by the self-diffusivity of water, phase change driving forces, water-ice graphene interactions, and convection in the water-graphene media. It is found that mass transport-related properties of DGAs, including pore size and directionality, show a significant dependence on freezing temperature, graphene oxide (GO) loadings, and synthesis vessel diameter-to-height ratio (D/H). For the freezing temperature change from -20 to -115 °C, the average pore size progressively decreased from 120 to 20 μm, and the pore directionality transitioned from lamellar to ill-defined structures. When GO loadings were increased from 2 to 10 mg/mL at a fixed freezing temperature, pore size reduction was observed with less defined directionality. Furthermore, the pore directionality diminished with an increased width-to-height aspect ratio of DGA samples due to the buoyancy-driven convective circulation, which interfered with the directional ice/pore growth. Understanding the comprehensive effects of these mechanisms enables the controlled growth of ice crystals, leading to graphene aerogels with highly directional microstructures.

Effect of CNTs length on thermophysical properties of paraffin/CNTs/graphene aerogel nanocomposite as a shape stabilized phase change material

In this work, paraffin/carbon nanotubes/graphene aerogel (Pa/CNTs/GA) nanocomposite with different CNTs lengths were synthesized. CNTs' length was changed by refluxing them in a mixture of acids for different times, by which the initial micrometer length of CNTs was reduced to 1200 and 205 nm after 0.5 and 1 h refluxing. To complete dispersing CNTs in paraffin, they were functionalized for the second time using dodecylamine. By inserting paraffin composites into the aerogel using vacuum impregnation, the thermal conductivity of the aerogel increases greatly. Melting and freezing latent heat of both samples of graphene aerogel composite containing 0.5 and 1 h refluxed CNTs was reduced compared to that of the pure paraffin and Pa/CNTs composite. The specific heat of the Pa/CNTs/GA composite containing 1 h refluxed CNTs was reduced compared to that of the Pa/CNTs (1 h refluxed) composite, but it was increased for the samples containing 0.5 h refluxed CNTs. Also, Pa/ZnO, Pa/TiO2, and Pa/Al2O3 composites were prepared and their thermophysical properties were compared with those of Pa/CNTs composites.

Bioinspired Graphene Aerogels with Hybrid Wettability for Solar-Driven Purification of Complex Wastewater.

Salt deposition and pollutant enrichment greatly hamper efficient and sustainable water production for a solar evaporator. Inspired by the desert beetle, a dual-region hydrophobic graphene/hydrophilic titanium dioxide (TiO2) aerogel (GTA) with internal hydrophilic-hydrophobic hybrid wettability structure is prepared via a facile freeze-drying and thermal reduction method. The evaporator shows adjustable wettability, optimized water content, and a low energy loss in the evaporation process. Simultaneously, the hybrid wetting structure in aerogel subjects salt to a dynamic crystallization-dissolution process to prevent salt deposition. The GTA solar evaporator achieves an evaporation rate of 1.52 kg·m-2·h-1 with a 91.02% efficiency under 1 sun irradiation. Furthermore, GTAs achieve a stable evaporation rate in high salinity brine (25 wt % NaCl) under 1 sun irradiation for 100 h, which could compete well with other most advanced photothermal evaporation materials. Moreover, the synergistic effect of graphene and TiO2 endows GTAs with excellent photocatalytic degradation and self-cleaning properties, which can effectively reduce the enrichment of contaminants on the evaporator. Therefore, GTA evaporators can efficiently and stably obtain clean water from seawater and wastewater, which provides a feasible strategy for the purification of complex wastewater.

Alternating current assisted preparation of three-dimensional graphene aerogels and the application in electromagnetic interference shielding

Three-dimensional (3D) graphene aerogels (GA) have obtained significant attention across various fields due to their lightweight and porous properties. Nevertheless, the development of a scalable and environmentally friendly method for synthesizing self-supported 3D GA remains a challenge. In this study, we introduced an innovative method for the preparation of 3D GA using alternating current (AC) strategy, which fully used the characteristic of AC's constantly changing current direction to attract graphene oxide (GO) particles to the electrode surface and subsequently reduced them to reduced GO (rGO). Ultimately, GA is self-assembled on the electrode surface under repeated cycles. An applied AC signal with optimal parameters produced a porous GA with an oxygen content of 10.76 at%, which is 66.67% less than that of the original GO. When applying GA to electromagnetic interference (EMI) shielding, it provides a maximum specific shielding effectiveness of 9100 dB cm2 g−1 at X-band due to the repeated reflection and absorption of electromagnetic waves (EMWs) by the abundant pore wall. Furthermore, the shielding effectiveness can be significantly improved to 68.60 dB at the X-band for a multilayer GA. Notably, it is worth emphasizing that this AC-assisted synthesis method has proven its adaptability to various metal electrodes, such as cost-effective iron and copper. Importantly, this method avoids the high-temperature treatments and the use of environmentally hazardous chemicals. It is envisaged that this environmentally friendly and low-cost approach will greatly facilitate the cost-effective production of 3D GA with diverse applications.

Graphene-Based Aerogels for Biomedical Application.

Aerogels are three-dimensional solid networks with incredibly low densities, high porosity, and large specific surface areas. These aerogels have both nanoscale and macroscopic interior structures. Combined with graphene, the aerogels show improved mechanical strength, electrical conductivity, surface area, and adsorption capacity, making them ideal for various biomedical applications. The graphene aerogel has a high drug-loading capacity due to its large surface area, and the porous structure enables controlled drug release over time. The presence of graphene makes it a suitable material for wound dressings, blood coagulation, and bilirubin adsorption. Additionally, graphene's conductivity can help in the electrical stimulation of cells for improved tissue regeneration, and it is also appropriate for biosensors. In this review, we discuss the preparation and advantages of graphene-based aerogels in wound dressings, drug delivery systems, bone regeneration, and biosensors.

Effect of graphene aerogel as a catalyst layer additive on performance of direct methanol fuel cell

Efficient methanol oxidation reaction is the first requirement of the electrocatalyst of a Direct methanol fuel cell (DMFC), which is determined by its catalyst material and preparation method. In this work, a novel electrocatalyst used in anode is prepared by using graphene aerogel (GA) as a supporting material with platinum and Nafion binder by spray coating. The physical and chemical properties of the electrocatalyst are examined with scanning electron microscope (SEM), Electrochemical impedance spectroscopy (EIS), and polarization curves. The SEM results show that graphene aerogel based electrocatalysts possess a three-dimensional structure with uniform dispersion of nanostructure, which enlarges the activation area of the electrocatalyst and produces more protons and electrons. Moreover, the well-developed porous structure provides a less resistance and smooth pathway for protons to reach the cathode. The results show that with 10 % GA and 50 % Nafion as binder, the current density reaches at the value of 42.62 mW·cm−2 respectively, which is 13.5 % higher than the maximum power density of 37.56 mW·cm−2 of traditional carbon-catalyst layer (C-CL) electrode. Moreover, when temperature increases from 50 to 70 ℃, the novel catalytic layer electrode (GA-CL) doped with GA as an additive delivers 95.8 % increment in power density.

Fabrication and performance of a 3D porous graphene aerogel-supported Ni–ZnS composite photocatalyst

The performance of a Ni–ZnS/three-dimensional (3D) graphene aerogel (GA) composite photocatalyst for hydrogen production was investigated in this study. Ni–ZnS precursor was loaded on 3D graphene aerogel through a simple solvothermal method, and the composite Ni–ZnS/GA was successfully synthesized. The average hydrogen production rate of Ni–ZnS/GA-4 can reached 12.06 mmol·g−1·h−1 and after three cycles for 9 h, the hydrogen production efficiency remained at 97.81%. Ni2+ doping provided suitable band gap for ZnS, which could fully absorb sunlight, and made the photo-generated carriers have sufficient redox ability. The large specific surface of 3D graphene gel enhanced the dispersion of nano Ni-ZnS, boosted photo-generated carrier separation, and accelerated sacrificial agent adsorption. The Ni–ZnS/GA composite had more active adsorption sites and photocatalytic reaction centers, improving photocatalytic activity and efficiency.

Construction of novel stable surface ion-imprinted graphene aerogels for efficient and selective extraction of lithium ion

Selective extraction of lithium from salt lake brine has attracted widespread attention in order to meet the growing global demand for lithium. Due to the high Mg2+/Li+ ratio and low Li+ concentration in salt lake brine, extracting Li+ from salt lake brine is extremely challenging. Herein, a novel approach was employed using graphene oxide (GO) with abundant functional groups as the skeleton material, and trihydroxymethyl aminomethane (Tris) as the pioneering reducing agent. Through the liquid phase self-assembly technology combined with surface modification, the Li+ imprinted three-dimensional block graphene aerogels (IDGAs) were successfully constructed under the assisted cross-linking effect of N,N-dimethylformamide (DMF). The IDGAs achieve good adsorption capacity (12.55 mg g−1), excellent regeneration performance, and comparatively high selectivity against Na+, K+, and Mg2+ of 4.75, 2.71, and 1.90, respectively. The exceptional properties of IDGAs can be attributed to the synergism resulting from the establishment of adsorption sites through the high specific surface area of the skeleton, as well as the selective recognition of Li+ by 2-hydroxymethyl-12-crown ether-4. Consequently, IDGAs represent a highly promising option for the efficient extraction of lithium from salt lake brine.

Synthesis of Graphene Aerogel for Adsorptive Removal of Tetracycline from Water: Impact of Operating Parameters

Graphene aerogel (GA) was synthesized by chemical reduction of graphene oxide (GO) using ethylene diamine as a reducing agent, which was then followed by a freeze-drying process. The morphology and surface properties of GA, GO samples were characterized by Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), Scanning electron microscopy (SEM), Energy-dispersive X-ray spectroscopy (EDX), and Brunauer-Emmett-Teller (BET). GA was then used to study the adsorption process of tetracycline (TC) in aqueous solutions. Different parameters influencing the adsorption efficiency of GA such as pH, adsorbent load, initial concentration of TC, contact time were investigated. The results showed that when GO was transformed to GA, the XRD characteristic peak at about 10.8˚ was shifted to broad peaks at 26˚ and 43˚, implying that the crystalline structure of GO was converted to GA which contained a large percent of amorphous structure and a smaller crystalline structure formed by stacking layers of graphene. The C/O ratio in GA sample was significantly increased compared to GO samples (6.5/1 compared to 1.38/1), suggesting that oxygen-containing functional groups (-OH, -C=O, -O-…) in GO were drastically reduced. The optimal conditions for the adsorption of TC were 10 mg L-1 TC solution, pH 7.0 at 75 min, 0.1 g L-1 of adsorbent, and at 30 °C. The adsorption process was better described by Langmuir isotherm model (R2=0.9938) compared to Freundlich one (R2=0.1302). The maximum adsorption capacity (Qmax) of GA calculated by the Langmuir model was 107.5 mg g-1, significantly higher than other common adsorbents. GA presented a stable and promising adsorbent for TC removal in water.

Hot-Pressed Super-Elastic Graphene Aerogel with Bidirectional Thermal Conduction Properties as Thermal Interface Materials

Traditional graphene-based films normally possess high thermal conductivity (TC) only along a single direction, which is not suitable for thermal interface materials (TIMs). Here, a graphene film with excellent bidirectional TC and mechanical properties was prepared by hot-pressing super-elastic graphene aerogel (SEGA). Thermal annealing at 1800 °C improves the further restacking of graphene sheets, bringing high structure stability to SEGA for enduring the hot-pressing process. The junctions and nodes between the graphene layers in the hot-pressed SEGA (HPSEGA) film provide bidirectional heat transport paths. The in-plane TC and through-plane TC of HPSEGA film with a thickness of 101 μm reach 740 Wm−1K−1 and 42.5 Wm−1K−1, respectively. In addition, HPSEGA film with higher thickness still maintains excellent thermal transport properties due to the interconnected structure reducing the effect of the defects. The infrared thermal images visually manifest the excellent thermal-transfer capability and thermal-dissipation efficiency of the HPSEGA films, indicating the great potential as advanced bidirectional TIMs.

Preferential ice growth on grooved surface for crisscross-aligned graphene aerogel with large negative Poisson’s ratio

Ice formation on solid surfaces is a ubiquitous process in our daily life, and ice orientation plays a critical role in anti-icing/deicing, organ cryo-preservation, and material fabrication. Although previous studies have shown that surface grooves can regulate the orientation of ice crystals, whether the parallel or perpendicular alignment to the grooves is still under debate. Here, we systematically investigate ice formation and its oriented growth on grooved surfaces through both in situ observation and theoretical simulation, and discover a remarkable size effect of the grooves. With the designability of surface groove patterns, the preferential growth of ice crystals is programmed for the fabrication of a crisscross-aligned graphene aerogel with large negative Poisson’s ratio. In addition, the size effect provides guidance for the design and fabrication of solid surfaces where the effective control of ice orientation is highly desired, such as efficient deicing, long time organ cryo-preservation, and ice-templated materials.

Strength and Deformation Behavior of Graphene Aerogel of Different Morphologies

Graphene aerogels are of high interest nowadays since they have ultralow density, rich porosity, high deformability, and good adsorption. In the present work, three different morphologies of graphene aerogels with a honeycomb-like structure are considered. The strength and deformation behavior of these graphene honeycomb structures are studied by molecular dynamics simulation. The effect of structural morphology on the stability of graphene aerogel is discussed. It is shown that structural changes significantly depend on the structural morphology and the loading direction. The deformation of the re-entrant honeycomb is similar to the deformation of a conventional honeycomb due to the opening of the honeycomb cells. At the first deformation stage, no stress increase is observed due to the structural transformation. Further, stress concentration on the junctions of the honeycomb structure and over the walls occurs. The addition of carbon nanotubes and graphene flakes into the cells of graphene aerogel does not result in a strength increase. The mechanisms of weakening are analyzed in detail. The obtained results further contribute to the understanding of the microscopic deformation mechanisms of graphene aerogels and their design for various applications.

Remarkable chemical adsorption and catalysis of monodisperse metallic cobalt sulfide nanoparticles enable long-cycling Li–S battery with high areal capacity and low shuttle constant

High-energy density lithium-sulfur battery is considered as one of the most potential new-generation energy-storage technologies. Nevertheless, the capacity decays rapidly due to severe volumetric change of sulfur, dissolution and slow redox kinetics of intermediate polysulfides, and instability of lithium anode. Herein, a novel highly conductive porous sulfur cathode host composed of graphene aerogel and polar Co9S8 nanoparticle is designed to address these obstacles. The porous conductive framework not only provides channels for rapid conduction of electron and lithium ion, but also provides adequate space to physically confine the lithium polysulfides and accommodate the volume expansion. Both experimental and theoretical calculations demonstrate that the in-situ uniformly deposited Co9S8 nanoparticles can effectively bind polar lithium polysulfides and catalyze their interconversion, and the shuttle effect is therefore effectively suppressed. The Co9S8-GA/S cathode exhibits high specific discharge capacity (1219.1 mAh g−1) and high areal specific capacity (14.3 mAh m−2) at 0.1 C, low shuttle constant (0.15 h−1), excellent rate performance (625.6 mAh g−1/7.4 mAh m−2 at 5 C), outstanding long cyclic stability (low decay of 0.024 %/cycle during 1000 cycles at 2 C). This study demonstrates a promising aerogel strategy to design high-performance composite cathode for lithium-sulfur battery.

Rapid immobilization of Cr(Ⅵ) from aqueous waste through multi-functionalized surface-modified lignin-based aerogels: Dynamic and mechanism analyses

Water containing heavy metal ions can be extremely harmful to the environment and human body, thus the development of low-cost and high-efficient adsorbents has an exciting prospect. In this study, lignin/graphene aerogels modified with polydopamine and polyethyleneimine, respectively, were successfully prepared to remove Cr(VI) from aqueous waste. The physicochemical properties of graphene aerogels (GA), lignin/graphene aerogels (LGA), polydopamine-modified lignin/graphene aerogels (LGA@PDA), polyethyleneimine-modified lignin/graphene aerogels (LGA@PEI) were investigated using FT-IR, Raman spectroscopy, XRD, XPS, SEM-EDS, and BET analysis. The results demonstrate that adsorbents have a high specific surface area, an interconnected porous structure, and a large number of oxygen-containing groups, making them particularly favorable for heavy metal adsorption. The effects of GO/lignin ratio, surface modifiers, solution pH, contact time, initial concentration and temperature on the Cr(VI) removal were investigated and compared via batch experiments. Compared with GA (138.74 ± 3.93 mg/g), the adsorption capacity of LGA with GO/LA ratio 40:1 increased to 167.66 ± 4.75 mg/g. Furthermore, the maximum adsorption capacity of LGA@PEI and LGA@PDA rose up to 209.85 ± 3.25 mg/g and 240.39 ± 3.26 mg/mg, respectively. By simulating the experimental data with different kinetic models and isotherm models, the adsorption processes of different lignin-derived aerogels were further explored under various conditions. All types of aerogels fit well with the pseudo-second-order model and Langmuir model. In addition, the XPS results confirm that the chemical reduction of Cr(VI) to Cr(III) also plays a role in the removal of Cr(VI). The results demonstrated that the removal effect of lignin-derived aerogels on Cr(VI) was greatly improved through the multi-functionalized surface modification of LGA with PDA and PEI. Furthermore, the removal efficiency of LGA@PDA and LGA@PEI for Cr(VI) remained stable after repeated regeneration. Therefore, the results of this study indicate that LGA@PDA and LGA@PEI are promising Cr(VI) adsorbents for practical applications in wastewater treatment.