Graphene Oxide Substrate Research Articles

Green composite synthesis based on aluminum fumarate metal-organic framework (MOF) for doxorubicin delivery: An in vitro study

The development of an eco-friendly and cost-effective drug delivery system (DDS) remains a challenge in cancer treatment. This study suggests a novel, eco-friendly, and cost-effective method to synthesize aluminum fumarate (A520) MOF using tangerine peel extract (TPE) as a pH-sensitive coating agent on a reduced graphene oxide (rGO) substrate. The system also incorporates the 2,2′-bipyridine dimethyltin diisothiocyanate complex, (Sn(bpy), as an organotin complex) to enhance therapeutic efficacy while minimizing off-target effects. In vitro cellular and molecular cytotoxicity examinations were conducted using HEK-293 and MCF-7 cell lines to evaluate cytotoxicity after 24 and 72 h. The findings of the MTT assay indicated that the final nanocarriers, without and with doxorubicin (DOX), exhibited relative cell viability of 95 % and 55 %, respectively, highlighting the system's potential for efficient and safe drug delivery. The TPE coating created a pH-sensitive DDS with high drug loading efficiency (DLE) (59.1 %) and low cytotoxicity. Drug release was studied over 200 h at pH 5.5 and 7.2. The augmented drug release profile (47 %) demonstrated a targeted release and successful inhibition of premature release in acidic environments due to pH-sensitive TPE molecules. The efficacy of targeted drug delivery to the MCF-7 cell was evaluated using 2D fluorescence microscopy, which demonstrated successful delivery of drugs to the cells. This innovative approach addresses the limitations of existing studies while promoting biocompatibility, stability, and functionality in DDSs.

Transition Metal-Gallium Intermetallic Compounds with Tailored Active Site Configurations for Electrochemical Ammonia Synthesis.

Gallium (Ga) with a low melting point can serve as a unique metallic solvent in the synthesis of intermetallic compounds (IMCs). The negative formation enthalpy of transition metal-Ga IMCs endows them with high catalytic stability. Meanwhile, their tunable crystal structures offer the possibility to tailor the configurations of active sites to meet the requirements for specific catalytic applications. Herein, we present a general method for preparing a range of transition metal-Ga IMCs, including Co-Ga, Ni-Ga, Pt-Ga, Pd-Ga, and Rh-Ga IMCs. The structurally ordered CoGa IMCs with body-centered cubic (bcc) structure are uniformly dispersed on the nitrogen-doped reduced graphene oxide substrate (O-CoGa/NG) and deliver outstanding nitrate reduction reaction (NO3RR) performance, making them excellent catalysts to construct highly efficient rechargeable Zn-NO3- battery. Operando studies and theoretical simulations demonstrate that the electron-rich environments around the Co atoms enhance the adsorption strength of *NO3 intermediate and simultaneously suppress the formation of hydrogen, thus improving the NO3RR activity and selectivity.

Hydrothermal-based controllable synthesis and structural-optical characterization of 2D-MoS2/graphene nanocomposites for optoelectronic applications

This study presents a two-dimensional (2D) nanocomposite of molybdenum disulfide/graphene (2D-MoS2/C) synthesized via a hydrothermal method at 230 °C for 2 h. Comprehensive characterization using XRD, FESEM, HRTEM, Raman spectroscopy, XPS, UV–Vis spectroscopy, and PL measurements revealed detailed microstructural, morphological, compositional, and optical properties. FESEM confirmed the uniform crystallization of ultrathin 2D MoS2 nanocrystals on graphene sheets, while TEM and HRTEM showed vertical growth of 2D MoS2 nanosheets (∼3–6 nm thick), forming a 2D MoS2/C architecture. XRD and Raman analyses verified the hexagonal 2H–MoS2 phase with minimal impurities, supported by XPS measurement. MicroRaman analysis indicated defect repair in graphene oxide substrate, evidenced by reduced D-band intensity and an enhanced 2D-band. The 2D MoS2/C nanocomposite exhibited significant photoluminescence with distinct emission peaks in the visible range (∼1.75–2.05 eV), surpassing the 2D MoS2 counterpart. Notably, 2D MoS2/C thin films showed high absorbance (∼83 %) compared to graphene oxide (∼48.4 %) and bare 2D MoS2 (∼22.1 %), highlighting enhanced light-matter interaction. This straightforward, cost-effective synthesis approach offers promising potential for MoS2/C nanocomposite applications in optoelectronics and catalysis.

Novel self-powered sandwich type Aptamer sensor for estrogen detection assisted with peroxidase mimic Cu-MOF

A novel self-powered and flexible enzymatic biofuel cell (EBFC)-based aptasensor was developed for the sensitive and selective detection of 17 β-estradiol (E2). A flexible polyvinyl alcohol (PVA)-tannic acid‑carbon nanotube/reduced graphene oxide (PTCR) substrate was modified with gold nanoparticles (AuNPs) and thiolated aptamer 1 (Apt1) to yield Apt1@AuNPs/PTCR. A copper-based metal-organic framework (Cu-MOF) with peroxidase mimicking activity was employed to anchor glucose oxidase (GOD) and Apt2, forming the Cu-MOF@GOD/Apt2 tag. When E2 was recognized by Apt1, the anchored E2 quantitatively recognized Cu-MOF@GOD/Apt2 to create a Cu-MOF@GOD/Apt2-E2-Apt1 sandwich structure for glucose oxidation to generate electrical power. Increased E2 concentrations enhanced Cu-MOF@GOD/Apt2 capture and amplified the electrical signal. The electrical power increased linearly as the E2 concentration increased from 1.0 pM to 1.0 nM. The sensor was successfully applied to various food samples and blood serum detection. This work promoted the application of novel self-powered biosensors for food safety analysis.

Design and Construction of Carbon-Coated Bimetallic Selenide Heterostructures Loaded on Reduced Graphene Oxide Substrate for Superior Lithium-Ion Storage.

In this work, carbon-coated bimetallic tin-nickel selenide heterostructures loaded on reduced graphene oxide composites were prepared through a metal-organic framework-assisted strategy. The carbon coating mitigates the volume expansion and maintains the structural stability, while the introduction of reduced graphene oxide and heterojunction enhances electrical conductivity and reaction kinetics, thereby together contributing to the enhanced lithium-ion storage performance. As expected, the optimal material delivers excellent lithium-ion storage performance in terms of a high reversible capacity of 1033.4 mAh g-1 at 0.2 A g-1, outstanding rate capability, and long-term cyclability with the capacity of 726.2 mAh g-1 after 500 cycles at 1.0 A g-1 and 452.4 mAh g-1 after 1000 cycles at 2.0 A g-1. Furthermore, the electrochemical reaction mechanism of the composite is analyzed.

Prussian Blue Anchored on Reduced Graphene Oxide Substrate Achieving High Voltage in Symmetric Supercapacitor.

In this work, iron hexacyanoferrate (FeHCF-Prussian blue) particles have been grown onto a reduced graphene oxide substrate through a pulsed electrodeposition process. Thus, the prepared FeHCF electrode exhibits a specific volumetric capacitance of 88 F cm-3 (specific areal capacitance of 26.6 mF cm-2) and high cycling stability with a capacitance retention of 93.7% over 10,000 galvanostatic charge-discharge cycles in a 1 M KCl electrolyte. Furthermore, two identical FeHCF electrodes were paired up in order to construct a symmetrical supercapacitor, which delivers a wide potential window of 2 V in a 1 M KCl electrolyte and demonstrates a large energy density of 27.5 mWh cm-3 at a high power density of 330 W cm-3.

Investigations on MoS2 plasma by infra-red pulsed laser irradiation in high vacuum

MoS2 targets were irradiated by infra-red (IR) pulsed laser in a high vacuum to determine hot plasma parameters, atomic, molecular and ion emission, and angular and charge state distributions. In this way, pulsed laser deposition (PLD) of thin films on graphene oxide substrates was also realized. An Nd:YAG laser, operating at the 1064 nm wavelength with a 5 ns pulse duration and up to a 1 J pulse energy, in a single pulse or at a 10 Hz repetition rate, was employed. Ablation yield was measured as a function of the laser fluence. Plasma was characterized using different analysis techniques, such as time-of-flight measurements, quadrupole mass spectrometry and fast CCD visible imaging. The so-produced films were characterized by composition, thickness, roughness, wetting ability, and morphology. When compared to the MoS2 targets, they show a slight decrease of S with respect to Mo, due to higher ablation yield, low fusion temperature and high sublimation in vacuum. The pulsed IR laser deposited MoS x (with 1 < x < 2) films are uniform, with a thickness of about 130 nm, a roughness of about 50 nm and a higher wettability than the MoS2 targets. Some potential applications of the pulsed IR laser-deposited MoS x films are also presented and discussed.

Thin Coatings of Polymer of Intrinsic Microporosity (PIM‐1) Enhance Nickel Electrodeposition and Nickel‐Catalyzed Hydrogen Evolution

AbstractNickel nanoparticle electrodeposition is studied on flat glassy carbon (GC) or on nitrogen‐doped reduced graphene oxide (rGO‐N) substrates. The effects of a very thin (nominally 16 nm) layer polymer of intrinsic microporosity (PIM‐1) are investigated (i) on enhancing nickel nanoparticle nucleation and growth during electrodeposition and (ii) on enhancing hydrogen evolution electrocatalysis. Beneficial effects are tentatively assigned to PIM‐1 suppressing blocking effects from interfacial hydrogen bubble formation. Exploratory data suggest that in aqueous 0.5 M NaCl solution (artificial seawater) nickel nanoparticles grown into a thin film of PIM‐1 could be a viable electrocatalyst with an onset of hydrogen evolution only slightly negative compared to that observed for platinum nanoparticles.

Synthesis of AgNPs/MnO2/rGO composite materials with adsorption properties and their application in analysis of anti-inflammatory and antibiotic agents

In this article, AgNPs and MnO2 were successively synthesized on the Graphene oxide (GO) substrate using an in situ method. The AgNPs/MnO2/GO nanocomposite material was modified onto the surface of a glassy carbon electrode (GCE) and the material was electrochemically reduced on the electrode surface. The material obtained after reduction was called AgNPs/MnO2/rGO, which was confirmed by X-Ray diffraction (XRD) and Fourier transform infrared spectroscopy (FT-IR) to examine the chemical bonding and by scanning electron microscopy (SEM) combined with energy-dispersive spectroscopy (EDS) to demonstrate the elemental characteristics of the material. In addition, X-ray photoelectron spectroscopy (XPS) analysis was performed to determine the elemental composition, chemical state, and electronic state of the elements on the surface of the material. The application of the reduced material was for the analysis of Piroxicam and Ofloxacin using the differential pulse anodic stripping voltammetry (DP-ASV) method. The investigation of pH and scan rate (v) indicated that the synthesized material had adsorption properties and was applied for the analysis of the anti-inflammatory drug Piroxicam and the antibiotic Ofloxacin.

Fabrication of a novel porous nanostructure based on NiCuFe2O4@MCM-48, embedded with graphene oxide/poly (p-phenylenediamine) to construct an efficient supercapacitor

In this study, a new nanocomposite was created by combining copper-doped nickel ferrite (NiCuFe2O4) nanoparticles with MCM-48 (Mobil Composition of Matter No. 48) on a graphene oxide (GO) substrate functionalized with poly(ρ-phenylenediamine) abbreviated as (PρPD). This nanocomposite was developed to investigate its potential for enhancing the function of a supercapacitor in energy storage. Following NiCuFe2O4@MCM-48 preparation, Hummer’s technique GO was applied. In-situ polymerization of NiCuFe2O4@MCM-48/GO nanoparticles with ρ-phenylenediamine (ρPD) in the presence of ammonium persulfate (APS) produced PρPD, a conductive polymer. Structural characterization of the nanocomposite includes FTIR, XRD, VSM, TGA-DTG, EDX, and FE-SEM. Results from BET indicate a pore size increase of up to 5 nm. Fast ion penetration and higher storage in capacitor material are explained by this. Additionally, the nanocomposite’s electrochemical performance was evaluated using GCD and CV tests. The NiCuFe2O4@MCM-48/GO/PρPD nanocomposite has a specific capacitance of 203.57 F g−1 (1 A g−1). Furthermore, cyclical stability is essential for energy storage applications. The nanocomposite retains 92.5% of its original capacitance after 3000 cycles, indicating outstanding electrochemical stability.

ELECTROCATALYSIS OF COBALT DOPED CeO2/rGO NANOCOMPOSITE FOR OXIDATION OF METHANOL AND FORMIC ACID

In this study,a novel cobalt-doped cerium oxide (CeO2)on reduced graphene oxide (rGO) substrate was successfully prepared through a hydrothermal method.The comprehensive characterization of the synthesized nanocomposite involved X-ray diffraction studies (XRD),Raman spectrum analysis,High Resolution Transmission Electron microscopy (HRTEM), and Field Emission Electron Microscopy (FE-SEM).The effective surface area of CeO2/rGO and Co-CeO2/rGO was determined using the Randles-Sevecik equation,revealing values of 4.02X10-5 cm2 and 6.35X10-5 cm 2 ,respectively.Cyclic Voltammetry (CV) was employed to investigate the electrochemical reversibility behavior, demonstrating promising results for Co-CeO2/rGO nanocomposite.Electrochemical impedance spectroscopy(EIS) further highlighted low charge transfer resistance (Rct) and enhanced double-layer capacitance (Cdl).Notably, the synthesized nanocomposite exhibited excellent electrocatalytic activity for methanol and formic acid oxidation in an acidic medium. Overall, this work provides valuable insights into the synthesis characterization, and electrochemical performance of Co-CeO2/rGO nanocomposite, showcasing their potential applications in energy- related processes.

Regulated Behavior in Living Cells with Highly Aligned Configurations on Nanowrinkled Graphene Oxide Substrates: Deep Learning Based on Interplay of Cellular Contact Guidance.

Micro-/nanotopographical cues have emerged as a practical and promising strategy for controlling cell fate and reprogramming, which play a key role as biophysical regulators in diverse cellular processes and behaviors. Extracellular biophysical factors can trigger intracellular physiological signaling via mechanotransduction and promote cellular responses such as cell adhesion, migration, proliferation, gene/protein expression, and differentiation. Here, we engineered a highly ordered nanowrinkled graphene oxide (GO) surface via the mechanical deformation of an ultrathin GO film on an elastomeric substrate to observe specific cellular responses based on surface-mediated topographical cues. The ultrathin GO film on the uniaxially prestrained elastomeric substrate through self-assembly and subsequent compressive force produced GO nanowrinkles with periodic amplitude. To examine the acute cellular behaviors on the GO-based cell interface with nanostructured arrays of wrinkles, we cultured L929 fibroblasts and HT22 hippocampal neuronal cells. As a result, our developed cell-culture substrate obviously provided a directional guidance effect. In addition, based on the observed results, we adapted a deep learning (DL)-based data processing technique to precisely interpret the cell behaviors on the nanowrinkled GO surfaces. According to the learning/transfer learning protocol of the DL network, we detected cell boundaries, elongation, and orientation and quantitatively evaluated cell velocity, traveling distance, displacement, and orientation. The presented experimental results have intriguing implications such that the nanotopographical microenvironment could engineer the living cells' morphological polarization to assemble them into useful tissue chips consisting of multiple cell types.

Synthesis of defect-engineered molybdenum sulfides on reduced graphene oxide for enhanced hydrogen evolution reaction kinetics

Amorphous molybdenum sulfide (a-MoS3) is a promising non-precious electrocatalyst for hydrogen evolution reaction owing to the abundant defective active sites. Here in, we show a rapid microwave-assisted synthesis method to produce a-MoS3 catalysts on reduced graphene oxide (rGO) substrates. The a-MoS3 reported in this study comprise of two possible 1D chain-like structures, i.e., with molybdenum (IV) in Weber's model and molybdenum (V) in Hibble's model, unlike the polymeric cluster type a-MoS3 structures reported in literature. Thermal annealing of the microwave-prepared a-MoS3 produced a family of defect-engineered MoSx/rGO hybrids, from a-MoS3 to crystalline MoS2, which showed tunable HER activities. XPS analysis provided in-depth understanding of the compositional changes in MoSx/rGO with thermal annealing. The a-MoS3/rGO 250 (annealed at 250 °C) exhibited the highest HER catalytic activity among all the MoSx/rGO hybrids, with an overpotential of 208 mV at 10 mA/cm2, a low Tafel slope of 52 mV/decade, a high double layer capacitance of 3.7 mF/cm2 and a high TOF value of 0.43 H2/s per site at the HER overpotential of 208 mV. The excellent HER activity is attributed to both MoV and sulfur active sites. This study provides a controllable, scalable and rapid synthesis method to produce 1D chain-like a-MoS3 structures for HER electrocatalysis.

Ni Nanoparticles on the Reduced Graphene Oxide Surface Synthesized in Supercritical Isopropanol.

Nanocomposites based on ferromagnetic nickel nanoparticles and graphene-related materials are actively used in various practical applications such as catalysis, sensors, sorption, etc. Therefore, maintaining their dispersity and homogeneity during deposition onto the reduced graphene oxide substrate surface is of crucial importance to provide the required product characteristics. This paper demonstrates a new, reproducible method for preparing a tailored composite based on nickel nanoparticles on the reduced graphene oxide surface using supercritical isopropanol treatment. It has been shown that when a graphene oxide film with previously incorporated Ni2+ salt is treated with isopropanol at supercritical conditions, nickel (2+) is reduced to Ni (0), with simultaneous deoxygenation of the graphene oxide substrate. The resulting composite is a solid film exhibiting magnetic properties. XRD, FTIR, Raman, TEM, and HRTEM methods were used to study all the obtained materials. It was shown that nickel nanoparticles on the surface of the reduced graphene oxide had an average diameter of 27 nm and were gradually distributed on the surface of reduced graphene oxide sheets. The data obtained allowed us to conduct a reconnaissance discussion of the mechanism of composite fabrication in supercritical isopropanol.

Alignment of Nematic Liquid Crystal 5CB Using Graphene Oxide

In this article, we employed the saturation voltage method (SVM) to investigate the interaction between a nematic liquid crystal (NLC) and a graphene oxide (GO) substrate. The SVM approach involved applying a potential difference (ΔV) to the cell containing the NLC (specifically, 5CB) to reorient the nematic director (n) from a parallel to a perpendicular configuration with respect to the cell’s surface. By utilizing sandwich cells with indium–tin oxide semi-transparent electrodes covered by GO, we measured the anchoring energy between the NLC and the thin GO film. To evaluate the strength of this anchoring energy, we compared the results with two other cells: one exhibiting strong anchoring energy (polyimide cell) and the other demonstrating weak anchoring energy (formvar cell). The influence of GO thin films on the alignment of nematic 5CB was distinctly observed.

Modulating the Schottky barrier heights of plasmonic metal/semiconductor heterojunctions by graphene substrates for boosting photocatalytic water oxidation

Construction of plasmonic metal/semiconductor heterojunctions represents a promising approach to extending the light absorption range and simultaneously maintaining the high redox potentials of photogenerated carriers. However, unsuitable Schottky barrier height (ΦB) blocks the metal-to-semiconductor injection of hot electrons and increases the probability of their recombination with hot holes. Herein, a verstile protocol is demonstrated to address this issue based on the introduction of a reduced graphene oxide (rGO) substrate. As a proof-of-concept design, a Au/TiO2/rGO stacked photocatalyst is fabricated with TiO2 sandwiched between rGO and Au. In this smart design, rGO with work function smaller than that of Au upshifts the Fermi level of Au/TiO2 and reduces the ΦB between Au and TiO2. As a result, the hot electron injection efficiency from plasmonic Au to the conduction band of TiO2 is greatly augmented, increasing the number of separated hot holes participating in H2O oxidation. Profitting from the enhanced utilization of hot carriers, the Au/TiO2/rGO delivers markedly improved photocatalytic activity in O2 evolution as compared with Au/TiO2. This work provides us guidance to build high-efficient plasmonic photocatalysts for renewable fuel production and highlights the importance in reinforcing the separation and transfer of hot charges.

Efficient HCHO oxidation at room temperature via maximizing catalytic sites in 2D coralloid δ-MnO2@GO

Airborne formaldehyde (HCHO) in indoor environments causes serious health problems and needs to be efficiently eliminated. However, the efficient and stable catalytic oxidation of HCHO can be hardly achieved at room temperature over transition metal oxides due to the limited exposure of active sites. Herein, δ-MnO2@GO catalysts were originally synthesized via a facile in situ growth of δ-MnO2 on the trace graphene oxide (GO) substrate (1%) and stably exhibited nearly 100% HCHO elimination at room temperature. δ-MnO2@GO showed the unique 2D coralloid structure with uniformly dispersed δ-MnO2 nanorod on planar-structured GO, which greatly enhanced the exposure of catalytic sites and mass transfer of reactants. The abundant surface reactive oxygen species (ROS) and hydroxyl (-OH) groups were rapidly generated from the activation of O2 and surface-adsorbed water over highly exposed catalytic sites. The ROS and -OH groups cooperated well cooperated to maintain the exceptional catalytic activity and stability towards HCHO degradation. In-situ DRIFTS results showed that catalytic HCHO oxidation predominantly follows the Langmuir-Hinshelwood (L-H) mechanism over the δ-MnO2@GO. This study presents a simple yet effective strategy for maximizing exposure to catalytic active sites and rational design of efficient catalysts for indoor HCHO elimination.

V2O5-Fe3O4/rGO Ternary Nanocomposite with Dual Applications as a Dye Degradation Photocatalyst and OER Electrocatalyst.

The design and synthesis of structured nanomaterials with dual properties have always been highly attractive in various fields, especially in the reduction of environmental pollution as well as the generation of renewable energy. In this study, the synthesized ternary V2O5-Fe3O4/rGO nanocomposite was investigated to evaluate both the photocatalytic and electrocatalytic activities for the removal of methylene blue (MB) dye under UV/visible light radiation and oxygen evolution reaction (OER), respectively. The magnetized V2O5-Fe3O4/rGO nanocomposite is characterized by TEM, FE-SEM (with coupling by elemental mapping), EDS, XRD, FTIR, Raman, PL, DRS, and UV-vis analyses. The obtained results show that the graphene oxide substrate is decorated very well using Fe3O4 and V2O5 nanoparticles and converted to reduced graphene oxide (rGO). Furthermore, the V2O5-Fe3O4/rGO nanocomposite is considered as an active catalyst material to modify the commercial glassy carbon electrode for OER using linear sweep voltammetry (LSV). The photocatalytic activity of this novel nanocomposite revealed 89.2% (kobs = 1.7 × 10-2 min-1) and 76% (kobs = 8.3 × 10-3 min-1) degradation efficiencies of MB dye under UV and visible light irradiation at room temperature, respectively, and the surface area of the V2O5-Fe3O4/rGO nanocomposite was examined to be 705.8 cm2/g by N2 adsorption-desorption isotherms. In addition, electrochemical measurements determined the best OER performance of the ternary nanocomposite with the lowest overpotential (458 mV) and Tafel slope (132 mV dec-1) compared to the rGO substrate, Fe3O4, V2O5 nanoparticles, and binary nanocomposites. This work shows much enhancements in both photocatalytic and electrocatalytic activities due to the synergistic effect of the decorated GO support with V2O5 and Fe3O4 nanoparticles.

A surface-enhanced Raman scattering sensor for the detection of benzo[a]pyrene in foods based on a gold nanostars@reduced graphene oxide substrate.

In this study, a simple and sensitive surface-enhanced Raman scattering (SERS) sensor based on gold nanostars@reduced graphene oxide (AuNS@rGO) was successfully developed for the detection of benzo[a]pyrene in foods. The detection strategy involved benzo[a]pyrene adsorption on reduced graphene oxide, followed SERS detection of adsorbed molecules. Owing to the large electric fields generated by the gold nanostars under laser irradiation, which greatly amplified the Raman signals of benzo[a]pyrene, very high sensitivity for the target analyte was achieved. Under optimized conditions, the SERS sensor exhibited a wide linear detection range for benzo[a]pyrene (from 0.1μgL-1 to 10000μgL-1), with a low limit of detection of 0.0028μgL-1. Chicken samples spiked with benzo[a]pyrene were assayed using the sensor, with recoveries ranging from 89.20% to 100.80%. The benzo[a]pyrene content in roasted mutton sample was quantified using the SERS sensor and a reversed-phase high-performance liquid chromatography method, with similar results being obtained.

High resistivity free-standing crosslinked graphene oxide substrates: hopping conduction mechanism and application to recyclable electronics

Graphene oxide (GO) is an oxidized derivative of graphene that can be formed into free-standing wafers by aqueous processing methods. We propose GO as a potential alternative printed electronic substrate material to mitigate the waste electronic and electrical equipment problem. By dissolving these substrates in water, GO permits the mechanical separation and recovery of discrete components from defunct circuits, thus closing the life cycle of printed circuits. In this work we measure the anisotropic, frequency dependent resistivity of free-standing GO wafers under DC and AC (f = 0.1 Hz–500 kHz) excitation and in varying relative humidity (RH) conditions. Unmodified GO and GO crosslinked with calcium ions, borate ions, and glutaraldehyde were characterized. AC resistivity measurements reveal charge transport in free-standing GO occurs by several distinct hopping conduction mechanisms that are sensitive to the crosslinking formulation. GO crosslinked with calcium ions exhibits the highest DC resistivity, 4.6 × 105 Ωm and 2.6 × 104 Ωm, for out-of-plane and in-plane directions, respectively, at 17% RH. Both AC and DC resistivities decrease with increasing RH. We demonstrate that GO wafers can be used as dielectric substrates in the construction of simple electronic circuits with discrete electronic components. Finally, we present a proof-of-concept for electrical trace and component recovery via disassembly of GO wafers in water.