Liquid Exfoliation Research Articles

Biocompatible 2D Materials via Liquid Phase Exfoliation.

2D materials (2DMs), such as graphene, transition metal dichalcogenides (TMDs), and black phosphorus (BP), have been proposed for different types of bioapplications, owing to their unique physicochemical, electrical, optical, and mechanical properties. Liquid phase exfoliation (LPE), as one of the most effective up-scalable and size-controllable methods, is becoming the standard process to produce high quantities of various 2DM types as it can benefit from the use of green and biocompatible conditions. The resulting exfoliated layered materials have garnered significant attention because of their biocompatibility and their potential use in biomedicine as new multimodal therapeutics, antimicrobials, and biosensors. This review focuses on the production of LPE-assisted 2DMs in aqueous solutions with or without the aid of surfactants, bioactive, or non-natural molecules, providing insights into the possibilities of applications of such materials in the biological and biomedical fields.

Design of cobalt-doped graphene quantum dot-decorated vanadium pentoxide nanosheet-based Off-On fluorescent sensor system for tiopronin sensing.

Despite the high medicinal value of tiopronin, there are substantial adverse effects such as yellow skin, yellow eyes, muscle aches, etc. Therefore, there is a huge necessity to identify tiopronin using advanced sensors in provided samples. Recently, the preference for graphene quantum dots (GQDs) and inorganic nanomaterial-based fluorescent sensors for the detection of pharmaceuticals has been extensively documented due to their plentiful advantages. Therefore, in this work, the cobalt-doped GQDs decorated vanadium pentoxide nanosheet-based fluorescence switch 'Off-On' sensor (Co-GQDs@V2O5-NS) was designed for highly sensitive and selective detection of tiopronin. Briefly, the green synthesis of highly fluorescent Co-GQDs was carried out using a hydrothermal method. Meanwhile, the synthesis of V2O5-NS was synthesized using the liquid exfoliation method. The synthesis of Co-GQDs@V2O5-NS was accomplished wherein Co-GQDs adsorbed on the surface of V2O5-NS that offered the quenching of fluorescence of Co-GQDs. Afterward, the addition of tiopronin into the quenched probe disclosed the proportional recovery of fluorescence of Co-GQDs. Here, the addition of tiopronin provides the decomposition of V2O5-NS and conversion into the V4+ that aids in releasing the quenched fluorescence of Co-GQDs. The limit of detection and linearity range for tiopronin was found to be 1.43ng/mL and 10-700ng/mL, respectively. Moreover, it demonstrated high selectivity, good stability at experimental conditions, and practicality in analyzing tiopronin in spiked sample analysis. Hence, the designed Co-GQDs@V2O5-NS nanosized sensor enables high sensitivity, selectivity, simplicity, label-free, and eco-friendly tiopronin recognition. In the future, the utility of Co-GQDs@V2O5-NS can open a new door for sensing tiopronin in provided samples.

Nanobubble-assisted liquid phase exfoliation of graphene in deionized water

In this study, we propose a novel method utilizing nanobubbles (NBs) to assist in liquid phase exfoliation. The size, thickness, and number of layers of the resulting graphene solution were characterized and quantified. A highly concentrated graphene solution was achieved through ultrasonic processing in deionized (DI) water, without the need for any surfactant. The observed increase in yield can be attributed to the heightened cavitation within the NBs solution. This study presents a sustainable and cost-effective approach for the large-scale production of graphene, aligning with green and eco-friendly principles.

Boron nitride nanosheets from high shear exfoliation for high-performance thermal conductivity films

Boron nitride nanosheets (BNNSs) with intrinsically ultra-high thermal conductivity have attracted more and more attention and various methods have been proposed to prepare BNNSs-based thermally conductive adhesives. In this work, a liquid phase shear exfoliation process was proposed to prepare BNNSs. BNNSs can be directly prepared by exfoliating h-BN particles dispersed in isopropanol at a controlled rotational speed range of 16,000–22,000 rpm and the maximum yield of BNNSs is up to 32.1%. After the BNNSs were modified with polydopamine (M-BNNSs), the dispersion performance of BNNSs in water was significantly improved. BNNSs were incorporated into a cellulose nanofiber-based adhesive, and the highly thermally conductive films were prepared by a flow-delay process. A tested in-plane thermal conductivity of up to 23.23 W·m−1·K−1 and excellent mechanical properties are demonstrated and thermal infrared images provide a more visual representation of the high thermal conductivity and heat dissipation properties of the film, indicating the promising application of the film in the field of thermal conductivity.

Novel electrochemical platform based on C3N4-graphene composite for the detection of neuron-specific enolase as a biomarker for lung cancer

Lung cancer remains the leading cause of cancer mortality worldwide. Small cell lung cancer (SCLC) accounts for 10–15% of cases and has an overall 5-years survival rate of only 15%. Neuron-specific enolase (NSE) has been identified as a useful biomarker for early SCLC diagnosis and therapeutic monitoring. This work reports an electrochemical immunosensing platform based on a graphene-graphitic carbon nitride (g-C3N4) nanocomposite for ultrasensitive NSE detection. The g-C3N4 nanosheets and graphene nanosheets were synthesized via liquid exfoliation and integrated through self-assembly to form the nanocomposite. This nanocomposite was used to modify screen-printed carbon electrodes followed by covalent immobilization of anti-NSE antibodies. The unique properties of the graphene-g-C3N4 composite facilitated efficient antibody loading while also enhancing electron transfer efficiency and electrochemical response. Systematic optimization of experimental parameters was performed. The immunosensor exhibited a wide linear detection range of 10 pg/mL to 100 ng/mL and low limit of detection of 3 pg/mL for NSE along with excellent selectivity against interferences. Real serum matrix analysis validated the applicability of the developed platform for sensitive and accurate NSE quantifica-tion at clinically relevant levels. This novel graphene-g-C3N4 nanocomposite based electro-chemical immunoassay demonstrates great promise for early diagnosis of SCLC.

Borophene Quantum Dots as Novel Peroxidase-Mimicking Nanozyme: A Dual-Mode Assay for the Detection of Oxytetracycline and Tetracycline Antibiotics.

The greater advantages and wide applications of zero-dimensional nanodots inspire researchers to develop new materials. Therefore, novel borophene quantum dots (QDs) were prepared by a hydrothermal liquid exfoliation technique using water medium. The borophene QDs proved to be highly stable in water medium for more than 120 days. The synthesized borophene QDs revealed intrinsic peroxidase mimetic activity using two chromogenic substrates, 3,3',5,5'-tetramethylbenzidine (TMB) and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid)diammonium salt (ABTS). The excellent intrinsic peroxidase activity toward TMB and ABTS substrates was executed using optimal reaction conditions (pH, borophene QDs' concentration, incubation time, and temperature). The formation of hydroxyl radicals in the presence of H2O2 upon TMB and ABTS oxidation played a significant role in the peroxidase reaction. The borophene QDs further proved to be successful for the colorimetric detection of antibiotics (oxytetracycline and tetracycline) using both TMB and ABTS peroxidase substrates. The limit of detection (LOD) for oxytetracycline and tetracycline was found to be 1.10 and 1.02 μM using TMB and 1.03 and 1.02 μM using ABTS chromogenic substrates, respectively. In addition, the fluorescence sensing of oxytetracycline and tetracycline over borophene QDs was also examined. The high fluorescence of borophene QDs (turn ON) was quenched (turn OFF) by oxytetracycline and tetracycline through the inner filter effect mechanism. The LOD of the fluorescence sensing of oxytetracycline and tetracycline was 1.14 and 1.08 μM, respectively. Interestingly, the borophene QDs could be used for the sensitive and selective colorimetric and fluorometric sensing of oxytetracycline and tetracycline after 120 days of storage. The synthesized borophene QDs with long-term stability and real sample analysis provide new insight as nanozymes with higher peroxidase mimetic and fluorescence performance and can be further exploited for medical diagnosis and environmental toxicants' detection.

Extremely Enhanced Photoluminescence in MoS2-Derived Quantum Sheets.

Molybdenum disulfide (MoS2) quantum sheets (QSs) are attractive for applications due to their tunable energy band structures and optical and electronic properties. The photoluminescence quantum yield (PLQY) of MoS2 QSs achieved by mechanical and liquid exfoliation and chemical vapor deposition is low. Some studies have reported that chemical treatment and elemental doping can improve the PLQY of transition metal dichalcogenides (TMDs), but this is limited by complex instruments and reactions. In this study, a heat treatment method based on a polar solvent is reported to improve the PLQY and photoluminescence (PL) intensity of MoS2 QSs at room temperature. The absolute PLQY of treated MoS2 QSs is increased to 18.5%, and the PL intensity is increased by a factor of 64. This method is also effective for tungsten disulfide (WS2) QSs. The PL enhancement of QSs is attributed to oxidation of the edges. Such passivation/deformation of MoS2 QSs facilitates the radiative route rather than the nonradiative route, resulting in extreme enhancement of the PL. Our work could provide novel insights/routes toward the PL enhancement of TMD QSs.

Exfoliation of Metal-Organic Frameworks to Give 2D MOF Nanosheets for the Electrocatalytic Oxygen Evolution Reaction.

The structure and properties of materials are determined by a diverse range of chemical bond formation and breaking mechanisms, which greatly motivates the development of selectively controlling the chemical bonds in order to achieve materials with specific characteristics. Here, an orientational intervening bond-breaking strategy is demonstrated for synthesizing ultrathin metal-organic framework (MOF) nanosheets through balancing the process of thermal decomposition and liquid nitrogen exfoliation. In such approach, proper thermal treatment can weaken the interlayer bond while maintaining the stability of the intralayer bond in the layered MOFs. And the following liquid nitrogen treatment results in significant deformation and stress in the layered MOFs' structure due to the instant temperature drop and drastic expansion of liquid N2 , leading to the curling, detachment, and separation of the MOF layers. The produced MOF nanosheets with five cycles of treatment are primarily composed of nanosheets that are less than 10 nm in thickness. The MOF nanosheets exhibit enhanced catalytic performance in oxygen evolution reactions owing to the ultrathin thickness without capping agents which provide improved charge transfer efficiency and dense exposed active sites. This strategy underscores the significance of orientational intervention in chemical bonds to engineer innovative materials.

Exfoliation of Metal–Organic Frameworks to Give 2D MOF Nanosheets for the Electrocatalytic Oxygen Evolution Reaction

AbstractThe structure and properties of materials are determined by a diverse range of chemical bond formation and breaking mechanisms, which greatly motivates the development of selectively controlling the chemical bonds in order to achieve materials with specific characteristics. Here, an orientational intervening bond‐breaking strategy is demonstrated for synthesizing ultrathin metal–organic framework (MOF) nanosheets through balancing the process of thermal decomposition and liquid nitrogen exfoliation. In such approach, proper thermal treatment can weaken the interlayer bond while maintaining the stability of the intralayer bond in the layered MOFs. And the following liquid nitrogen treatment results in significant deformation and stress in the layered MOFs’ structure due to the instant temperature drop and drastic expansion of liquid N2, leading to the curling, detachment, and separation of the MOF layers. The produced MOF nanosheets with five cycles of treatment are primarily composed of nanosheets that are less than 10 nm in thickness. The MOF nanosheets exhibit enhanced catalytic performance in oxygen evolution reactions owing to the ultrathin thickness without capping agents which provide improved charge transfer efficiency and dense exposed active sites. This strategy underscores the significance of orientational intervention in chemical bonds to engineer innovative materials.

ReS2/CoS heterostructure catalysts for electrochemical application in hydrogen evolution and supercapacitor

Development of Nano-heterostructures based on transition metal chalcogenides is promising strategy to accelerate the catalytic performance for hydrogen evolution reaction (HER) and supercapacitor application. The design and development of non-noble transition metal based catalysts is required for the low-cost, efficient and earth-abundant electrodes for sustainable energy conversion and storage. ReS2/CoS heterostructures were synthesized by two step methods involving liquid phase exfoliation of ReS2 and hydrothermal decoration of CoS. The prepared ReS2/CoS heterostructures shows high performance supercapacitor applications with specific capacitance of 663.2 F/g at 2 A/g and 643.1 F/g at scan rate 5 mV/s, showing enhanced redox reaction and number of electrochemically active sites due to synergistic effect and modulated electronic structure. Additionally, ReS2/CoS heterostructures shows the superior HER performance in alkaline condition with overpotential of 187 mV at 10 mA/cm2 due to accelerated kinetics, enhanced ECSA and low charge transfer resistance. The ReS2/CoS heterostructures shows the stable electrochemical performance for HER for more than 17 h.

An efficient fluorescence sensor based on chitosan-modified graphitic carbon nitride for selective determination of Cu2+ ions

An effective, feasible and novel fluorescence sensor based on modified graphitic carbon nitride (g-C3N4) was constructed for the detection of Cu2+ ions. Carbon nitride nanosheets were obtained by liquid exfoliation in an acid solution and then modified by chitosan with an abundance of active sites. The as-prepared material was characterized by various methods including SEM, FT-IR, XRD, Raman, UV–vis and XPS. The modification material emitted enhanced fluorescence at 433 nm under the excitation of 368 nm and exhibited fluorescence quenching behaviors in the presence of Cu2+. The fluorescence intensity decrement was proportional to the concentration of Cu2+ ions ranging from 0 to 4.0 μM and 4.0 to 50.0 μM with a detection limit as low as 9 nM under optimal conditions. As a result of the improved sensing performance, the as-prepared g-C3N4-based material presented strong affinity, sensitivity, specificity and stability for metal ions and had a promising application for fluorescence detection.

Passively mode-locked Er-doped fiber laser with single and double wavelength pulses based on germanene saturable absorber

In this paper, we focus on the single crystal material germanium (Ge), which is fabricated into saturable absorbers (SAs) employing liquid phase exfoliation, and validate it with an erbium-doped fiber laser (EDFL). The Ge SA was obtained with a modulation depth of 9.8% and a saturation intensity of 11.02 MW cm−2. The single-wavelength mode-locked pulse with a minimum pulse width of 847 fs was obtained at a cavity length of 10.5 m. In addition, at a cavity length of 106 m, a dual-wavelength mode-locked phenomenon was obtained in which the central wavelengths were located at 1559.20 nm and 1561.31 nm. The experimental results show that Ge nanosheets in an EDFL provide a strong basis for the development of nonlinear optics and have a wide range of applications in the field of pulsed fiber lasers.

A photodetector based on p-GaN/N-MoS2 QDs heterojunction with high responsivity

Molybdenum disulfide (MoS2) is the most thoroughly investigated for photodetection applications with direct bandgap transition in low-dimensional structures, high light–matter interaction, and good carrier mobility. In this work, MoS2 quantum dots was synthesis by liquid exfoliation and characterized using scanning electron microscopy (SEM), Transmission electron microscopy (TEM), Fluorescence emission spectra (FES), UV–vis spectroscopy, and Photoluminescence (PL). The average size is ∼ 3.6 nm with strong absorption in the UV region and a band gap of 4.49 eV. Moreover, a novel structure of N- MoS2 QDs \\ p-GaN heterojunction photodetector was deposited by spray coating. The PL of N- MoS2 QDs \\ p-GaN emission spectra expanded from UV to visible light with high responsivity to the visible light of 7.06 mA W−1 and detectivity of 1.24 × 1010 jones.

Utilizing ultrasonic liquid exfoliation for producing graphene from rice stem: Exploring cellular components and functionalities

This study investigates a prospective and straightforward method for producing graphene material derived from biomass, examining the influence of plant cell composition and functions. The experimental outcomes highlight ultrasound's crucial role in synthesizing graphene material sourced from biomass. Ultrasound, a pivotal element in the experiment, significantly affects graphene production from biomass by working synergistically with the liquid components in the solvent system. Notably, the ethanol content reduces the solution’s surface tension, facilitating the effective dispersion of biochar and graphene oxide sheets throughout the process. Simultaneously, the water content maintains the solution’s polarity, enhancing the cavitation effect induced by ultrasound. Biomass-derived graphene is exfoliated utilizing an ultrasonic bath system (134.4 W, 40 kHz, 0.5 W/cm2) from biochar. The as-synthesized graphene oxide exhibits a structure comprising a few layers while remaining intact, featuring abundant functional groups. Interestingly, the resulting product displays nanopores with an approximate diameter of 100 nm. These nanopores are attributed to preserving specific cell structures, particularly those with specialized cell wall structures or secondary metabolite deposits from biomass resources. The study's findings shed light on the impact of cellular structure on synthesizing graphene material sourced from biomass, emphasizing the potential application of ultrasound as a promising approach in graphene production.

WSe2/BN heterostructure as saturable absorber for a diode-pumped passively Q-switched 2 µm solid-state laser.

We have successfully achieved the synthesis of heterojunction consisting of WSe2 and BN, by using a liquid phase exfoliation method, and characterization of the prepared materials under the microstructure. The WSe2/BN heterojunction was used as a saturable absorber in the Tm:YAP laser for passively Q-switched operation, and a pulsed laser with an output wavelength around 2 µm range was successfully obtained. After comparing the effects of resonators composed of different cavity mirrors, it is concluded that when the curvature radius of the input mirror is 250 mm and the transmittance of the output coupler is 2.5%, the best output performance was obtained. The maximum average output power of 834 mW was achieved, with a pulsed repetition frequency of 43.51 kHz and a minimum pulse duration of 1.28 µs, corresponding to a peak power of 14.97 W and a maximum single pulse energy of 19.17 µJ.

Ferroelectric Polarization Enhanced Photodetector Based on Layered NbOCl2

NbOCl2 is an emerging ferroelectric layered material with unique optoelectronic properties, in which the built‐in electric field caused by spontaneous polarization can independently drive the separation and transport of photoexcited electrons and holes. However, the optoelectronic performance of NbOCl2 and its device application have remained elusive. Here, few‐layer NbOCl2 is prepared by the liquid exfoliation method and used to construct photoelectrochemical (PEC)‐type photodetectors. The photodetectors are self‐powered with broadband photoresponse and long‐term cycle stability. Due to the built‐in electric field generated by the spontaneous polarization, the whole system exhibits an open circuit potential of approximately 0.205 V. Interestingly, the open circuit potential can be significantly increased to 0.446 V after poling treatment. The responsivity without external bias is increased by about 2.5 times after 1 V poling and by about 4 times after a poling time of 500 s. Moreover, the tunable ferroelectric polarization shows memory effect and retains about 25% enhancement in photocurrent density even after 60 min. The tuneability of the built‐in electric field in PEC systems based on NbOCl2 offers numerous possibilities for the development of photodetectors and nonvolatile memory devices.

Long lived photogenerated charge carriers in few-layer transition metal dichalcogenides obtained from liquid phase exfoliation.

Semiconducting transition metal dichalcogenides are important optoelectronic materials thanks to their intense light-matter interaction and wide selection of fabrication techniques, with potential applications in light harvesting and sensing. Crucially, these applications depend on the lifetimes and recombination dynamics of photogenerated charge carriers, which have primarily been studied in monolayers obtained from labour-intensive mechanical exfoliation or costly chemical vapour deposition. On the other hand, liquid phase exfoliation presents a high throughput and cost-effective method to produce dispersions of mono- and few-layer nanosheets. This approach allows for easy scalability and enables the subsequent processing and formation of macroscopic films directly from the liquid phase. Here, we use transient absorption spectroscopy and spatiotemporally resolved pump-probe microscopy to study the charge carrier dynamics in tiled nanosheet films of MoS2 and WS2 deposited from the liquid phase using an adaptation of the Langmuir-Schaefer technique. We find an efficient photogeneration of charge carriers with lifetimes of several nanoseconds, which we ascribe to stabilisation at nanosheet edges. These findings provide scope for photocatalytic and photodetector applications, where long-lived charge carriers are crucial, and suggest design strategies for photovoltaic devices.

Preparation and characterization of sulphur and zinc oxide Co-doped graphitic carbon nitride for photo-assisted removal of Safranin-O dye.

Recently, there has been significant interest in photocatalytic reactions involving graphitic carbon nitride (g-C3N4) due to its sp2-hybridized carbon and nitrogen content and it is an ideal candidate for blending with other materials to enhance performance. Here, we have synthesized and analyzed both doped and undoped g-C3N4 nanoparticles. Specifically, we co-doped sulfur (S) into g-C3N4, integrated it with ZnO particles, and investigated the photocatalytic potential of these nanocomposites to remove Safranin-O dye. The initial step involved the preparation of pure g-C3N4 through calcination of urea. Subsequently, S-g-C3N4 was synthesized by calcining a mixture of urea and thiourea with a 3 : 1 ratio. Finally, the ZnO-S-g-C3N4 composite was synthesized using the liquid exfoliation technique, with distilled water serving as the exfoliating solvent. These samples were characterized by advanced techniques, including UV-Vis spectroscopy, Fourier-transform infrared spectroscopy (FTIR), X-ray Diffraction (XRD), energy dispersive X-ray (EDX) and scanning electron microscopy (SEM), to assess their crystallinity, morphology, optical properties, and phase purity. Subsequently, these nanocomposites were employed in catalytic and photocatalytic processes to remove the Safranin-O dye (SO). The results highlighted the formation of Z-scheme junction responsible for ZnO-S-g-C3N4's significant performance improvement. The comparison of results demonstrated that S-g-C3N4 and ZnO-S-g-C3N4 composites revealed an effective removal of Safranin-O dye in the presence of UV-light as compared to pure g-C3N4, as it was attributed to the phenomenon of improved separation of photogenerated charge carriers as a result of heterojunction formation between S-g-C3N4 and ZnO interfaces. In addition to improving photocatalytic performance, this study presents a facile route for producing ZnO-S-g-C3N4 composite with superior adsorption capabilities and selectivity.

Hydrogen storage capacity of two-dimensional MoS2

Hydrogen storage holds a crucial place for the future of the world in terms of green energy. Two-dimensional materials, in particular, are important in this regard. The aim of this study is to evaluate the performance of MoS2 which is one of the most popular member of two-dimensional materials family. To do this, bulk and exfoliated MoS2 were used. Firstly, the liquid phase exfoliation method was employed to obtain exfoliated MoS2 layers. Then, the hydrogen storage potential of the bulk and exfoliated MoS2 was addressed under 1, 3, 5, 7, and 9 bar hydrogen pressure. After the absorption process, all the samples were characterized using XRD, Raman Spectrometer, and BET ahead of evaluating their hydrogen storage potential. The XRD pattern showed that the peak positions of bulk and exfoliated MoS2 were not affected critically by hydrogen storage. In the Raman spectra, the A1g and E2g1 peaks of all hydrogenated materials shifted to low wavelengths. Moreover, the BET measurements revealed that the specific surface area and the pore size of the bulk MoS2 were 12.31 m2/g and ≤67.46 nm respectively. Additionally, the specific surface area and the pore size of the exfoliated MoS2 were 23.16 m2/g and ≤69.28 nm, respectively. The hydrogen storage potential of the bulk and the exfoliated MoS2 was evaluated through an MFC in sccm unit. The bulk and exfoliated MoS2 stored 220 and 450 sccm hydrogen, respectively. Besides, the weight percent hydrogen storage for H–MoS2 and H-exfoliated MoS2 was determined to be 1.2 and 2.4 wt%, respectively. In summary, this study has shown that exfoliated MoS2, one of the two-dimensional materials, can play a critical role for hydrogen storage due to their high specific surface area.

Improving the liquid phase exfoliation efficiency of graphene based on the enhanced intermolecular and interfacial interactions

The liquid phase exfoliation (LPE) technique presents significant advantages and potential for the large-scale production of high-quality graphene nanosheets (GNs) with minimal defects. Nevertheless, the Hansen solubility parameters and surface tension matched principle were limited the range of suitable solvents for LPE process. As a result, commonly employed solvents such as N-methyl-2-pyrrolidone (NMP) and N, N-Dimethylformamide (DMF) exhibit low viscosity, leading to a low transmission efficiency of shear force from solvent to graphite, resulting in inadequate shear force and low exfoliation efficiency. In this work, to break through limitations of existing solvent systems, we investigate the influence of solvent viscosity on the LPE efficiency in various pyrrolidone solvents, which share similar structures with NMP but have longer molecular chains and higher viscosity. When compared to the NMP system, the concentration of GNs in the N-octyl-2-pyrrolidone (NOP) suspension system exhibits a significant increase of approximately 70 %, which primarily attributed to the higher intermolecular and interfacial interactions in NOP suspension. Moreinterestingly, the interactions could be further intensified by reducing the operating temperature in the NOP suspension system, which leading to an about 150 % improvement in LPE efficiency when compared to the NMP system at standard temperature. Given the remarkable conductivity of GNs, the prepared Cellulose nanofibers/graphene nanosheets (CNF/GNs) composite film exhibits lightweight and efficient electromagnetic shielding performance of 2.4 × 104 dB cm2 g−1.This work is expected to establish a universal and efficient pathway for the economical and high-yield production of GNs, elucidating the microscopic mechanism by which molecular conformation at the solid–liquid interface influences the transfer of shear forces from solvent to graphite, thereby promoting the development of widespread applications of GNs ang other two-dimensional (2D) nanomaterials.