Reversible Redox Research Articles

Amorphous Cobalt Polyselenides with Hyperbranched Polymer Additive as High-Capacity Magnesium Storage Cathode Materials Through Cationic and Anionic Co-Redox Mechanism.

Rechargeable magnesium batteries (RMBs) are a promising energy-storage technology with low cost and high reliability, while the lack of high-performance cathodes is impeding the development. Herein, a series of amorphous cobalt polyselenides (CoSex, x>2) is synthesized with the assistance of organic amino-terminal hyperbranched polymer (AHP) additive and investigated as cathodes for RMBs. The coordination of cobalt cations with the amino groups of AHP leads to the formation of amorphous CoSex rather than crystalline CoSe2. The amorphous structure is favorable for magnesium-storage reaction kinetics, and the polyselenide anions provide extra capacities besides the redox of cobalt cations. Moreover, the organic AHP molecules retained in CoSex-AHP provide an elastic matrix to accommodate the volume change of conversion reaction. With a moderate x value (2.73) and appropriate AHP content (11.58%), CoSe2.7-AHP achieves a balance between capacity and cycling stability. Amorphous CoSe2.7-AHP provides high capacities of 246.6 and 94 mAh g‒1, respectively, at 50 and 2000 A g‒1, as well as a capacity retention rate of 68.5% after 300 cycles. The mechanism study demonstrates CoSex-AHP undergoes reversible redox of Co2+/3+↔Co0 and Sen 2‒↔Se2‒. The present study demonstrates amorphous polyselenides with cationic-anionic redox activities is as a feasible strategy to construct high-capacity cathode materials for RMBs.

Unlocking Electrode Performance of Disordered Rocksalt Oxides Through Structural Defect Engineering and Surface Stabilization with Concentrated Electrolyte

Abstract Li‐excess cation‐disordered rocksalt oxides can boost the energy density of rechargeable batteries by using anionic redox, but the inferior reversibility of anionic redox hinders its use for practical applications. Herein, a binary system of Li3NbO4–LiMnO2 is targeted and the systematic study on factors affecting electrode reversibility, i.e., percolation probability, electronic conductivity, defect concentrations, and electrolyte solutions, is conducted. A Mn‐rich sample, Li1.1Nb0.1Mn0.8O2, delivers a smaller reversible capacity compared with a Li‐rich sample, Li1.3Nb0.3Mn0.4O2, because of the limitation of ionic migration associated with insufficient percolation probability for disordered oxides. Nevertheless, a larger reversible capacity of Li1.3Nb0.3Mn0.4O2 originates from excessive activation of anionic redox, leading to the degradation of electrode reversibility. The superior performance of Li1.1Nb0.1Mn0.8O2, including Li ion migration kinetics and electronic transport properties, is unlocked by the enrichment of structural defects for nanosized oxides. Moreover, electrode reversibility is further improved by using a highly concentrated electrolyte solution with LiN(SO2F)2 through the surface stabilization on high‐voltage exposure. Superior capacity retention, >100 cycles, is achieved for nanosized Li1.1Nb0.1Mn0.8O2. The electrolyte decomposition and surface stabilization mechanisms are also carefully examined, and it is revealed that the use of highly concentrated electrolyte solution can effectively prevent lattice oxygen being further oxidized and transition metal ion dissolution.

Expanding the Scope of Aluminum Chemistry with Noninnocent Ligands.

ConspectusAluminum is the most abundant metal in the earth's crust at 8%, and it is also widely available domestically in many countries worldwide, which ensures a stable supply chain. To further the applications of aluminum (Al), such as in catalysis and electronic and energy storage materials, there has been significant interest in the synthesis and characterization of new Al coordination compounds that can support electron transfer (ET) and proton transfer (PT) chemistry. This has been achieved using redox and chemically noninnocent ligands (NILs) combined with the highly stable M(III) oxidation state of Al and in some cases the heavier group 13 ions, Ga and In.When ligands participate in redox chemistry or facilitate the breaking or making of new bonds, they are often termed redox or chemically noninnocent, respectively. Al(III) in particular supports rich ligand-based redox chemistry because it is so redox inert and will support the ligand across many charge and protonation states without entering into the reaction chemistry. To a lesser extent, we have reported on the heavier group 13 elements Ga and In, and this chemistry will also be included in this Account, where available.This Account is arranged into two technical sections, which are (1) Structures of Al-NIL complexes and (2) Reactivity of Al-NIL complexes. Highlights of the research work include reversible redox chemistry that has been enabled by ligand design to shut down radical coupling pathways and to prevent loss of H2 from unsaturated ligand sites. These reversible redox properties have in turn enabled the characterization of Class III electron delocalization through Al when two NIL are bound to the Al(III) in different charge states. Characterization of the metalloaromatic character of square planar Al and Ga complexes has been achieved, and characterization of the delocalized electronic structures has provided a model within which to understand and predict the ET and PT chemistry of the NIL group 13 compounds. The capacity of Al-NIL complexes to perform ET and PT has been employed in reactions that use ET or PT reactivity only or in reactions where coupled ET/PT affords hydride transfer chemistry. As an example, ligand-based PT reactions initiate metal-ligand cooperative bond activation pathways for catalysis: this includes acceptorless dehydrogenation of formic acid and anilines and transfer hydrogenation chemistry. In a complementary approach, ligand based ET/PT chemistry has been used in the study of dihydropyridinate (DHP-) chemistry where it was shown that N-coordination of group 13 ions lowers kinetic barriers to DHP- formation. Taken together, the discussion presented herein illustrates that the NIL chemistry of Al(III), and also of Ga(III) and In(III) holds promise for further developments in catalysis and energy storage.

The measurement of one‐electron redox potentials of free radicals

AbstractThe paper is devoted to the measurements of one‐electron redox potentials of transient free radicals Eo. These values can be measured in the reversible redox reactions of radicals under investigation with a reference pair, which Eo is known. Several Eo of transient radicals are presented. The convenient and important objects for Eo measurement are quinone/semiquinone radical‐anions. A general problem of measurement of thermodynamic properties of short‐lived transients is discussed.

Regulating Phase Transition and Restraining Fe Distortion at High Potential Window via Rare Earth Metal Incorporation on O3‐Type Layered Cathodes

AbstractRapid capacity fading and structural collapse, along with other deep‐rooted challenges in the high‐voltage region, are insufficient to meet the requirements for commercial applications of O3‐type layered cathodes. Hereby, rare earth metal (RE) within the IIIB group are utilized as the robust dopants for O3‐NaNi1/3Fe1/3Mn1/3O2 (NFM) to achieve the purpose of reconstructing the crystal lattice and regulating the interlayer structure. The inactive RE3+ acts as a pillar, reinforces the TMO6 octahedron, and broadens the Na+ diffusion layer in the configuration of O‐Na‐O‐TM (RE)‐O‐Na‐O, giving rise to the enhanced crystal stability and accelerating the transmission of sodium ions. More impressively, the scandium incorporation is working as a “vitamin” that improves Ni/Fe redox reversibility, alleviating the irreversible P3‐O3’‐P3’ phase transformation and further restraining the disordered Fe migration into the neighboring Na layer, which is firmly validated by in situ X‐ray diffraction coupled with the synchrotron X‐ray absorption spectroscopy. Consequently, the as‐designed NFM‐Sc exhibits impressive rate capability (82.5 mAh g−1 at 10 C) and excellent cycle stability with 80.2% capacity retention after 500 cycles at the high voltage of 4.2 V. Given this, the elaborate work may shed new insight into the operational mechanism of rare metal through strategically regulating the structure for sodium‐ion batteries.

Highly reversible tin redox chemistry for stable anode-free acidic proton battery

Highly reversible tin redox chemistry for stable anode-free acidic proton battery

Fluorine-doped K0.39Mn0.77Ni0.23O1.9F0.1 microspheres with highly reversible oxygen redox reaction for potassium-ion battery cathode

Fluorine-doped K0.39Mn0.77Ni0.23O1.9F0.1 microspheres with highly reversible oxygen redox reaction for potassium-ion battery cathode

Effect of fluoride (CoF2) based electrode material for high energy and power density asymmetric flexible supercapacitors

Herein, an asymmetric supercapacitor (ASC) device was assembled by employing the pristine CoF2 as active positive electrode material and activated carbon (AC) as negative electrode material. The CoF2 electrode exhibited an outstanding electrochemical behavior with enhanced specific capacitance (Cs) of 872 F/g at 1 A/g current density in three electrode configurations. The reversible Faradaic redox reactions in CoF2 instigate the formation of cobalt-oxyfluorides and generating the mixed valence state of Co (Co2+ and Co3+) which improves its electrical conductivity and electrochemical behaviors. Furthermore, the room temperature paramagnetic nature of CoF2 increases the gradient force of ions which could possibly increase the redox reactions at the electrolyte/electrode interface. The constructed asymmetric device structure of CoF2//AC revealed a quasi-rectangular shaped cyclic voltametric curve and symmetrical semi-triangular shaped galvanostatic charge-discharge profiles, respectively, which affirms the combined electric double layer capacitance and pseudocapacitive nature by its hybrid assembly. Hence, the constructed CoF2//AC ASC demonstrated a remarkable specific capacitance of 141 F/g, energy density of 44.06 Wh.Kg−1, and power density of 422.97 W.Kg−1 at 1 A/g with the high cell voltage of 1.5 V. The CoF2//AC ASC device retained c.a. 92 % of its initial capacitance and attained over 96 % of Coulombic efficiency after 2000 cycles of charge-discharge profiles at 1 A/g, which suggests the high electrochemical stability. This admirable electrochemical performance and the origin towards the magneto-capacitance of CoF2 could pave a new way to explore next generation high-performance supercapacitors.

Control of Photoisomerization Kinetics via Multistage Switching in Bimetallic Ru(II)-Terpyridine Complexes.

In this study, we carried out detailed experimental and theoretical investigation on photophysical, electrochemical, and photoisomerization behaviors of a new array of luminescent binuclear Ru(II) complexes derived from a phenylene-vinylene-substituted terpyridyl ligand possessing RT lifetimes within 60.3-410.5 ns. The complexes experienced trans-to-cis isomerization in MeCN on irradiation with visible light, accompanied by significant changes in their absorption and emission spectral profiles. The reverse cis-to-trans process is also possible with the use of ultraviolet (UV) light. On conversion from trans to cis isomers, the emission intensity increases substantially, while for the reverse process, luminescence quenching occurs. Thus, "off-on" and "on-off" emission switching is facilitated upon treatment with visible and UV light alternatively. By the use of chemical oxidants (ceric ammonium nitrate and potassium permanganate) and reductants (metallic sodium) as well as light of appropriate wavelengths, multistate switching phenomena involving reversible oxidation-reduction and trans-cis isomerization have been achieved. Interestingly, the rate of this multistate photoswitching process becomes much faster compared to only two-state trans-cis isomerization of these complexes. Density functional theory (DFT) and time-dependent-DFT (TD-DFT) calculations are also performed to obtain a clear picture of the electronic environment of the complexes and also for the appropriate assignment of absorption and emission spectral bands.

Recent Research in Solar-Driven Hydrogen Production

Climate concerns require immediate actions to reduce the global average temperature increase. Renewable electricity and renewable energy-based fuels and chemicals are crucial for progressive de-fossilization. Hydrogen will be part of the solution. The main issues to be considered are the growing market for H2 and the “green” feedstock and energy that should be used to produce H2. The electrolysis of water using surplus renewable energy is considered an important development. Alternative H2 production routes should be using “green” feedstock to replace fossil fuels. We firstly investigated these alternative routes through using bio-based methanol or ethanol or ammonia from digesting agro-industrial or domestic waste. The catalytic conversion of CH4 to C and H2 was examined as a possible option for decarbonizing the natural gas grid. Secondly, water splitting by reversible redox reactions was examined, but using a renewable energy supply was deemed necessary. The application of renewable heat or power was therefore investigated, with a special focus on using concentrated solar tower (CST) technology. We finally assessed valorization data to provide a tentative view of the scale-up potential and economic aspects of the systems and determine the needs for future research and developments.

Band Structure Engineering Promotes Anionic Redox Reversibility of Cobalt-Free Li-Rich Layered Oxides Cathodes.

Li-rich layered oxides cathodes (LLOs) have prevailed as the promising high-energy-density cathode materials due to their distinctive anionic redox chemistry. However, uncontrollable anionic redox process usually leads to structural deterioration and electrochemical degradation. Herein, a Mo/Cl co-doping strategy is proposed to regulate the relative position of energy band for modulating the anionic redox chemistry and strengthening the structural stability of Co-free Li1.16Mn0.56Ni0.28O2 cathodes. The incorporation of Mo with high d state orbit and Cl with low electronegativity can narrow the band energy gap between bonding and antibonding bands via increasing the filled lower-Hubbard band (LHB) and decreasing the non-bonding O 2p energy bands, promoting the anionic redox reversibility. In addition, strong covalent Mo─O and Mn─Cl bonding further increases the covalency of Mn─O band to further stabilize the O2 n- species and enhance the reversible distortion of MnO6 octahedron. The strengthening electronic conductivity, together with the epitaxial structure Li2MoO4 facilitates the fast Li+ kinetics. As a result, the dual doping material exhibits enhanced anionic redox reversibility and suppressed oxygen release with increased cyclic stability and excellent rate performance. This strategy provides some guidance to design high-energy-density LLOs with desirable anionic redox reversibility and stable crystal structure via band structure engineering.

Unveiling Phenoxazine's Unique Reversible Two-Electron Transfer Process and Stable Redox Intermediates for High-Performance Aqueous Zinc-ion Batteries.

The low specific capacity determined by the limited electron transfer of p-type cathode materials is the main obstruction to their application towards high-performance aqueous zinc-ion batteries (ZIBs). To overcome this challenge, boosting multi-electron transfer is essential for improving the charge storage capacity. Here, as a typical heteroaromatic p-type material, we unveil the unique reversible two-electron redox properties of phenoxazine in the aqueous electrolytes for the first time. The second oxidation process is stabilized in the aqueous electrolytes, a notable contrast to its less reversibility in the non-aqueous electrolytes. A comprehensive investigation of the redox chemistry mechanism demonstrates remarkably stable redox intermediates, including a stable cation radical PNO⋅+ characterized by effective electron delocalization and a closed-shell state dication PNO2+. Meanwhile, the heightened aromaticity contributes to superior structural stability during the redox process, distinguishing it from phenazine, which features a non-equivalent hybridized sp2-N motif. Leveraging these synergistic advantages, the PNO electrodes deliver a high capacity of 215 mAh g-1 compared to other p-type materials, and impressive long cycling stability with 100 % capacity retention over 3500 cycles. This work marks a crucial step forward in advanced organic electrodes based on multi-electron transfer phenoxazine moieties for high-performance aqueous ZIBs.

Exploring the synergistic potential of mixed metal sulfides in hybrid supercapacitors

In energy reservoirs, hybrid supercapacitors (HSCs) have gained incredible recognition owing to their exceptional specific energy (Es), Specific power (Ps), and high cyclic stability. However, electroactive electrode materials with flashing electrochemical features and high storage ability are still required. In this regard, nickel-cobalt binary sulfide composites need further exploration as an electrode material owing to their high electrochemical properties, better conductivity, excellent redox reversibility, and high-rate capability. Here, we account the electrochemical activities and synthesis of composites including (nickel and cobalt sulfides). The composites were analyzed for structural and morphological analysis using XRD and SEM techniques, respectively. Amidst all other compositions, Ni0.75Co0.25S exhibited the optimum electrochemical performance measured in half-cell assembly with specific capacity (Qs) of 1147.6 Cg−1 and 900 Cg−1 at lowest scan rate and current density respectively. This electroactive electrode material together with activated carbon (AC) was further utilized in two cell assembly. This Hybrid device revealed ES of 50.21 Whkg−1 and Ps of 9350 Wkg−1 with capacity retention of 80.30% after consecutive charge discharge. The performance analysis of the actual device was further examined using a simulation approach, focusing on both capacitive and diffusive contributions by comparing the results of both linear and quadratic models. These attractive results revealed by Ni0.75Co0.25S signify it as favorable electrode material for hybrid supercapacitor applications.

Oxygen Vacancy‐Rich Defects Porous Cu2MgO3/Mg0.78Cu0.22O Composite with Sinter‐Resistant and Highly Reactive for Long‐Duration High‐Temperature Thermochemical Energy Storage

AbstractHigh‐temperature thermochemical energy storage based on metal oxides is the key technology to reducing the levelized costs of electricity of the next‐generation concentrated solar power plants. CuO/Cu2O has wide availability and high energy density, but severe sintering leads to low reactivity. In this study, an innovative approach to modulate the oxygen vacancy content to change the surface properties and crystal structure to enhance the sintering resistance and redox reversibility is proposed. The re‐oxidation degree is increased from 46% to 99%, and the energy release rate is increased by 3.5 times. It remains 99.9% reduction and 97.1% oxidation activity after 3000 cycles, which is very valuable for engineering applications. Cu2MgO3 and Mg0.78Cu0.22O are prone to form oxygen vacancies, which promotes the formation of porous structures. Mg0.78Cu0.22O helps Cu2MgO3/CuO/Cu2O deliver more O through the surface. Mg0.78Cu0.22O is firmly and uniformly dispersed on the CuO/Cu2O surface after long cycling. They have a large binding energy, more charge transfer and enhanced bond energy at the interface. The mechanism of composite in increasing the sintering temperature and long‐term reaction stability is revealed from experimental and theoretical calculations, which provides a new idea for the rational design of thermochemical energy storage materials.

Microwave-induced defect-rich vanadium sulfide cathodes for highly reversible electrochemical magnesium storage

Vanadium sulfide (VS4) demonstrates the most prospect as the cathode materials for rechargeable magnesium battery due to its special one-dimensional linear crystal structure. However, VS4 cathode still suffers from sluggish kinetics, irreversible structural change, short cycle life, and low capacity. Herein, a microwave-induced synthesis method is presented to fabricate VS4 nanosheets with rich sulfur vacancies and high V3+/V4+ ratio. When serviced as the cathode material for rechargeable magnesium battery, the VS4 nanosheets display excellent electrochemical performances with large specific capacity of 701 mAh/g at 200 mA g−1 current density. In addition, the VS4 nanosheets cathodes also show long-term operating stability over 600 cycles at 1.0 A/g current density with only 0.3 % capacity decay per cycle. Our experimental results show that the improved electrochemical reaction kinetics is ascribed to the defect-rich structure and the reversible anionic redox reactions between S2−/S22− of the VS4 nanosheets. This work offers a meaningful way to design high-performance Mg2+ ion storage cathode materials with favorable diffusion kinetics.

One–step synthesis of silver nanoparticles by lignocellulose nanofibrils to obtain antimicrobial hydrogels with accelerated wound healing

Lignin–containing cellulose nanofibrils (LCNF) have attracted extensive attention in the field of antibacterial due to the properties both of lignin and nanofibrils. The evenly distributed nano–lignin in LCNF can reduce Ag+, and the fiber network structure of nanofibrils may prevent the sedimentation of silver nanoparticles (AgNPs), which makes LCNF promising candidates for one–step preparation and deposition of AgNPs. Herein, carboxylated lignocellulose nanofibrils (CLCNF) with high stability were used to initiate the redox reaction. AgNPs (∼10.45 nm) were successfully prepared and homogeneously anchored onto CLCNF (Ag–L NPs–CLCNF). After compositing with polyvinyl alcohol (PVA) and tetracycline hydrochloride (TH), Ag–L NPs–CLCNF constructed a reversible redox quinone/catechol chemistry, imparting hydrogels with long–lasting reproducible adhesion and antimicrobial activity. Moreover, the incorporation of Ag–L NPs–CLCNF significantly improved the tensile strength (30.87 kPa), compressive strength (368.11 kPa) and thermal stability of the hydrogels, and that the Ag–L NPs–CLCNF hydrogel were self–healing. Importantly, the hydrogel containing Ag–L NPs–CLCNF can realize the controlled delivery of TH, giving it excellent antibacterial activity with accompanied good biocompatibility and significantly promoting full–thickness skin wound healing. This work offers a novel idea for preparing antibacterial hydrogels from lignocellulosic nanofibrils and the hydrogels have great application prospects in wound dressing.

Rod-like Ni-CoS2@NC@C: Structural design, heteroatom doping and carbon confinement engineering to synergistically boost sodium storage performance

Currently, conversion-type transition metal sulfides have been extensively favored as the anodes for sodium-ion batteries due to their excellent redox reversibility and high theoretical capacity; however, they generally suffer from large volume expansion and structural instability during repeatedly Na+ de/intercalation. Herein, spatially dual-confined Ni-doped CoS2@NC@C microrods (Ni-CoS2@NC@C) are developed via structural design, heteroatom doping and carbon confinement to boost sodium storage performance of the material. The morphology of one-dimensional-structured microrods effectively enlarges the electrode/electrolyte contact area, while the confinement of dual-carbon layers greatly alleviates the volume change-induced stress, pulverization, agglomeration of the material during charging and discharging. Moreover, the introduction of Ni improves the electrical conductivity of the material by modulating the electronic structure and enlarges the interlayer distance to accelerate Na+ diffusion. Accordingly, the as-prepared Ni-CoS2@NC@C exhibits superb electrochemical properties, delivering the satisfactory cycling performance of 526.6 mA h g−1 after 250 cycles at 1 A g−1, excellent rate performance of 410.9 mA h g−1 at 5 A g−1 and superior long cycling life of 502.5 mA h g−1 after 1,500 cycles at 5 A g−1. This study provides an innovative idea to improve sodium storage performance of conversion-type transition metal sulfides through the comprehensive strategy of structural design, heteroatom doping and carbon confinement.

Redox behaviour of boron subphthalocyanine carbon nanotube composites

Organic redox-active carbon composites can be used as sustainable electrode materials in electrochemical energy storage systems. Among numerous redox active species, peripherally dodecafluorinated boron subphthalocyanines (F12BsubPcs) have shown electrochemical redox activities in the solution phase. Nonetheless, the electrochemical properties of solid F12BsubPcs when compositing with nano carbon warrants further investigation for potential applications in energy storage. In this work, nanometer scale axially brominated F12BsubPcs (Br-F12BsubPcs) were coated onto bare graphitized multiwalled carbon nanotubes (GCNT) and COOH-functionalized GCNT (COOH-GCNT) by a facile dip coating method to produce two composites and to compare the effects of the surface functional group interactions with Br-F12BsubPcs. While the surface chemical and morphological characterizations confirmed the presence of Br-F12BsubPc coating on both bare and COOH-GCNTs, the coverage on the latter was higher. Cyclic voltammetric studies in acidic electrolyte revealed a highly reversible redox couple on both composites with Br-F12BsubPc coated COOH-GCNT demonstrating up to c.a. 70% higher redox peak currents than with Br-F12BsubPc coated GCNT. Further analyses of the coated COOH-GCNT suggested a 2-electron transfer process. The charge transfer has fast-kinetics and a strong dependence on the proton concentration. The composites produced in this work demonstrate potential for future application in energy storage and can provide a strategy for developing BsubPc-based carbon composites.

Securing Reversibility of UVO2+/UVIO22+ Redox Equilibrium in [emim]Tf2N‐Based Liquid Electrolytes towards Uranium Redox‐Flow Battery

AbstractWe studied electrochemical behavior of UVO2+/UVIO22+ in non‐aqueous liquid electrolytes to clarify what is required to attain its reversibility for utilizing depleted U in a redox‐flow battery. To transfer knowledge from former pyrochemical systems in high temperature molten salts, 1‐ethyl‐3‐methylimidazolium bis(trifluoromethyl)sulfonylamide ([emim]Tf2N) ionic liquid was employed here. As a result, a reversible redox reaction of the UVO2+/UVIO22+ was successfully observed on a glassy carbon working electrode under presence of Cl− in [emim]Tf2N, where [UVIO2Cl4]2−+e−=[UVO2Cl4]3− occurs after stabilization of both U oxidation states by the Cl− coordination. The observed electrochemical responses are rather sensitive to an electrode material, so that cyclic voltammograms on a Pt working electrode were actually irreversible. To improve diffusivity of solutes, viscosity (η) of [emim]Tf2N diluted with an auxiliary molecular solvent, N,N‐dimethylformamide (DMF), was examined under absence and presence of Cl−. When the mole fraction of DMF (xDMF) is 0.769, η of the mixture becomes sufficiently low to be utilized as a liquid electrolyte. Finally, we have succeeded in demonstrating a reversible redox reaction of [UVIO2Cl4]2−+e−=[UVO2Cl4]3− in the [emim]Tf2N‐DMF (50 : 50 v/v, xDMF=0.769) liquid electrolyte containing [Cl−]=0.519 M, where η=6.2 mPa ⋅ s.

Electrochemical detection of paracetamol using zeolitic imidazolate framework and graphene oxide derived zinc/nitrogen-doped carbon

A composite of zeolitic imidazolate frameworks and graphene oxide (ZIF-GO) derived 3D–2D Zn/N-doped carbon (ZnNC-rGO) was developed for the electrochemical detection of the analgesic paracetamol (PCT). The pyrolysis of ZIF-GO led to the formation of a nanoscale structure featuring ZnNC cubes embedded in rGO sheets. The Zn0-to-ZnO phase transition was found to mediate electrons during the reversible paracetamol redox reactions, which contributed to the sensing current response. Upon 800 °C heating under a N2 atmosphere, the mesoporosity of ZnNC-rGO(800) was significantly enhanced, thereby increasing the electrochemical surface area and charge transfer efficiency. The electrode sensitivity was optimized at a calibration linearity of 0.526 μA μM−1) with detection limit (0.077 μM) in the range of 0.5 – 70 μM using differential pulse voltammetry mode (DPV). The precision of analytical recovery for trace paracetamol concentrations was maintained based on the excellent reproducibility and selectivity trials in the presence of interference chemicals and in real water samples.