High Electron Transfer Rate Research Articles

Nanobioengineered Al2O3 Core-Shell Nanoparticle Preparation Using Bauhinia Variegate Plant Extract for Efficient Photocatalysis and Electrochemical Sensing.

Core-shell-based nanomaterials have garnered considerable attention in the recent past not only in catalytic applications but also in their potentiality in selective and efficient sensing. Present research reports the first and successful biosynthesis of the core (c-Al2O3)-shell nanoparticles (NPs) using Bauhinia variegate blossom extract as reducing and capping agents. The synthesized c-Al2O3 NPs were characterized and utilized to fabricate nanobioengineered electrodes on indium tin oxide (ITO) substrates via electrophoretic deposition. Electrochemical analysis, including cyclic voltammetry and differential pulse voltammetry, revealed quasi-reversible processes with high electron-transfer rates (Ks = 0.66 s-1) and a diffusion coefficient (D = 5.84 × 10-2 cm2 s-1). The electrode exhibited a very high sensitivity (23.44 μA μM-1 cm-2) and a low detection limit (0.463 μM) for sodium azide (NaN3) over two linear ranges of 1-6 and 8-20 μM. Additionally, c-Al2O3 NPs demonstrated the effective photocatalytic degradation of crystal violet dye under visible light, following pseudo-first-order kinetics. The fabricated electrode showed excellent selectivity, stability, and reproducibility, highlighting its potential for environmental monitoring and clinical diagnostics.

Sinusoidal LED light recipes can improve rocket edible biomass and reduce electricity costs in indoor growth environments.

Accumulation of edible biomass by crop plants relies on maintenance of a high photosynthetic rates across the photoperiod, with assimilation rate (A) generally responding to increasing light intensity in a hyperbolic fashion. In natural environments light fluctuates greatly over the course of the day, however in Controlled Environmental Agricultural (CEA) systems, light intensity can be supplemented or precisely controlled using LEDs to create near optimum conditions. In such indoor growth environments light is often delivered as a square wave and recommendations to horticulturalists are given in the form of Daily Light Integrals (DLI). However, this does not take into account the slow photosynthetic induction at the start of the photoperiod and the decline of A towards the end of the photoperiod, which has been demonstrated by several previous studies. Square wave light regimes therefore potentially cause suboptimal photosynthetic utilization of the applied lighting and waste electricity. Here we have adapted light recipes to gradually increase and decrease in intensity to take account of these findings. We demonstrate that, utilising a sinusoidal light regime capped at 250 μmol m-2 s-1, it is possible to increase edible biomass of rocket (by ca. 20%) compared to square wave delivered at 250 at the same DLI. Additionally, this can be achieved using less electricity (0.6%), therefore reducing energy costs and improving profitability. We suggest that capping maximum light intensity at 250 µmol m-2 s-1 improves the operating efficiency of PSII photochemistry (Fq'/Fm') also known as the photosynthetic efficiency by maintaining A later in the photoperiod. We show that a higher electron transfer rate (ETR) is maintained in these treatments over the photoperiod compared to higher light intensity caps, resulting in a greater Daily Photochemical Integral (DPI). We attribute this to less NPQ due to a greater sink capacity for the end products of electron transport, ATP and NADPH, as A is kept high for longer.

Fabrication of Nanobioengineered Interfaces Utilizing Quaternary Nanocomposite for Highly Efficient and Selective Electrochemical Biosensing of Urea.

Nanobioengineered interfaces have gained attention owing to their small size and high surface area-to-volume ratio for utilization as a platform for highly selective and sensitive biosensing applications owing to the integration of biological molecules with engineered nanomaterials/nanocomposites. In this work, a novel Ag-complex, [(PPh3)2Ag(SCOf)]-based quaternary Ag-S-Zn-O nanocomposites (NCs), was synthesized through an environmentally-friendly process. The results revealed the formation of the NCs with an average crystallite size and particle size of 36.08 and 40.22 nm, respectively. In addition, this is the first study to utilize such NCs synthesized via a single-source precursor method, offering enhanced sensor performance due to their unique structural properties. Further, these NCs were used to fabricate a urease (Ur)/Ag-S-Zn-O NCs/ITO nanobioengineered electrode for precise and sensitive electrochemical biosensing of urea. The interfacial kinetic studies revealed quasi-reversible processes with high electron transfer rates and linear current responses, indicating efficient reaction dynamics. A high diffusion coefficient and low surface concentration suggested a fast diffusion-controlled process, affirming the electrode's potential for rapid and sensitive urea detection. The biosensor demonstrated notable sensing properties such as high sensitivity (12.56 μA mM-1 cm-2) and a low detection limit (0.54 mM). The fabricated bioelectrode was highly selective and reproducible and demonstrated stability for up to 60 days. These results validate the potential of this nanobioengineered interface for next-generation biosensing applications, paving the way for advanced point-of-care diagnostics and real-time health monitoring.

Enhancement of Photoelectric Conversion Efficiency in Dye-Sensitized Solar Cells Using SnO2–TiO2 Composite Nanofibers

SnO2 is a wide-band gap N-type semiconductor material with a higher electron transfer rate than TiO2. Therefore, SnO2 has broad application prospects in the photoanode composite materials of dye-sensitized solar cells (DSSC). In this study, SnO2–TiO2 composite nanofibers with different molar ratios (5%, 10%, 15%, and 20%) were prepared by double-needle electrospinning technology, and the nanofibers were characterized after adjusting the solution composition. Different molar ratios of TiO2 and SnO2–TiO2 composite nanofiber photoanodes were fabricated by spin-coating, and the adsorption behavior of dyes on the photoanodes was investigated. Moreover, the electrochemical impedance of the photoanodes and DSSC and their photoelectric performance were also tested. The experimental results showed that SnO2–TiO2 composite nanofibers with a molar ratio of 10% exhibited excellent properties, including a peak specific surface area of 93.01 m2/g, strong dye adsorption capacity, small interfacial resistance, and fast electron transfer rate. These outstanding properties significantly promoted the generation of photoelectrons and improved the photoelectric conversion efficiency of DSSC. Compared with single-component TiO2, the photoelectric conversion efficiency of SnO2–TiO2 nanofiber photoanode composite material improved by 85.65%.

Ag-La(OH)3@Dy2O3 hybrid composite modified laser-induced graphene surface for simultaneous electrochemical detection of bisphenol A and tartrazine

Laser-induced graphene (LIG), created through CO2 laser irradiation of polyimide film (PI) substrates, has emerged as a versatile and promising material in numerous fields. However, despite its potential, a comprehensive exploration of LIG’s surface structure and reactivity remains absent in the literature, which is crucial for advancing its applications in electrochemical and electroanalytical fields. In this study, we developed and examined the interfacial structure and electronic behavior of an Ag-La(OH)3@Dy2O3 hybrid composite-modified LIG system as a model. We employed scanning electrochemical microscopy (SECM) to investigate these properties, extending our analysis to the simultaneous detection of organic pollutants, such as bisphenol A (BPA) and tartrazine (TRZ), in real samples. Compared to previous LIG production techniques, the LIG-modified electrode demonstrated a high electron transfer rate at the interface. The tailored LIG substrate showed excellent electrochemical activity towards electrochemical oxidation and simultaneous electroanalytical applications for BPA and TRZ with low detection limits (BPA: 9.2 nM, TRZ: 0.96 nM) in neutral physiological conditions. As a proof of concept, an extension to the real-time application of simultaneous monitoring of BPA and TRZ in various food samples was successfully demonstrated.

Electrode modified with CO2 laser-reduced graphene oxide-silver nanoparticles for determination of nitrite in water

Intercalation of rGO with AgNPs was achieved photothermally through CO2-assisted laser irradiation of GO and Ag+ precursors in the solid state. A uniform distribution of AgNPs was anchored on rGO (LrGO-AgNPs). The LrGO-AgNPs nanocomposite was structurally and electrochemically characterized. The parameters for the fabrication of LrGO-AgNPs and electrochemical NO2− detection were optimized. Under optimal conditions, the glassy carbon electrode (GCE) modified with LrGO-AgNPs showed a high diffusion coefficient and electron transfer rate constant for NO2− oxidation. Aditionally, the modified electrode displayed outstanding electrocatalytic activity toward NO2− oxidation with a sensitivity of 114.6 μA μM−1 cm−2 and an estimated response time of 7 s. The linear concentration range, LOD, and LOQ were 0.1–10,000, 0.039, and 0.131 μM, respectively. The proposed amperometric sensor was applied to detect carcinogenic nitrite in water samples and obtained recoveries between 93 ± 3 % and 103.3 ± 0.3 %. The results of the proposed method and the UV–vis spectrophotometric method showed no significant differences, indicating the potential of the proposed sensor for wider applications.

Nanomolar detection of organic pollutant -tartrazine in food samples using zinc-metal organic framework/carbon nano fiber - composite modified screen-printed electrode

In this study, we achieved a significant breakthrough by applying a binder-free Zn-MOF@CNF composite as a modifier on a screen-printed electrode (SPE) to achieve highly sensitive and selective detection of tartrazine (TRZ). This composite, with its unique rod-like structure for Zn-MOF and a curl thread-like morphology for carbon nanofibers (CNF), demonstrated a remarkable threefold increase in the sensing current of TRZ at a lower anodic oxidation potential (0.92 V) compared to the bare SPE. The Zn-MOF@CNF/SPE also exhibited a reduced charge transfer resistance of 61.9 Ω, elevated electrochemical active surface area of 0.416 cm2, and high heterogeneous electron transfer rate constant (k0) of 9.77×10−5 cm s−1. Furthermore, it displayed a broad linear range from 0.2 μM to 1000 μM with a remarkable sensitivity of 0.136 µAµM−1cm−2 and an impressive detection limit of 54 nM. Ultimately, the developed Zn-MOF@CNF/SPE sensor demonstrated excellent selectivity amidst various structurally similar overlapping species, outstanding repeatability, reproducibility, and stability in TRZ detection. The practical applicability of Zn-MOF@CNF/SPE was validated through 97 – 100.9 % recovery results in food samples such as jelly, ice cream, soft drinks, and candies.

Molecular dynamics study of the anticorrosive lubricating effects and interfacial behavior of dicarboxylic acid alcohol amine

In this study, water-soluble additives with excellent performance were designed, and their anticorrosive, tribological characteristics, and antibacterial properties were evaluated. Combined with molecular dynamics (MD), the interfacial behavior of additives on metal surfaces was investigated at the atomic scale. The results showed that the additive molecules could reduce the wear rate of ethylene glycol aqueous (EGaq) by 94.7 %, exhibiting excellent anticorrosive efficiency while also possessing certain antibacterial properties. MD results indicated that the additive could firmly adhere to the metal surface due to its higher electron transfer rate, and the interfacial interaction energy increased with the extension of the carbon chain. The coexistence of longer alkyl chains and frictionally active elements ensured the overall stability of the adsorption film.

Electrochemical aptasensors based on porous carbon derived from graphene oxide/ZIF-8 composites for the detection of Erwinia cypripedii

In this research, self-screening aptamer and MOFs-derived nanomaterial have been combined to construct electrochemical aptasensor for environmental detection. By utilizing the large specific surface area of reduced graphene oxide (rGO), ZIF-8 was grown in situ on surface of rGO, and the composites was pyrolyzed to obtain MOFs-derived porous carbon materials (rGO-NCZIF). Thanks to the synergistic effect between rGO and NCZIF, the complex exhibits remarkable characteristics, including a high electron transfer rate and electrocatalytic activity. In addition, the orderly arrangement of imidazole ligands within ZIF-8 facilitated the uniform doping of nitrogen elements into the porous carbon, thereby significantly enhancing its electrochemical performance. After carboxylation, rGO-NCZIF was functionalized with self-screening aptamer for fabricating electrochemical aptasensor, which can be used to detect Erwinia cypripedii, a kind of quarantine plant bacteria, with detection limit of 4.92 × 103 cfu/mL. Due to the simplicity and speed, the aptasensor is suitable for rapid customs inspection and quarantine. Additionally, the universality of this sensing strategy was verified through exosomes detection by changing the aptamer. The results indicated that the rGO-NCZIF-based electrochemical aptasensor had practical value in the environmental and medical fields.

Fe Single-Atom Carbon Dots Nanozyme Collaborated with Nucleic Acid Exonuclease III-Driven DNA Walker Cascade Amplification Strategy for Circulating Tumor DNA Detection.

Circulating tumor DNA (ctDNA), as a next-generation tumor marker, enables early screening and monitoring of cancer through noninvasive testing. Exploring the development of new methods for ctDNA detection is an intriguing study. In this work, a unique electrochemical biosensor for the ctDNA detector was constructed in the first utilizing Fe single-atom nanozymes-carbon dots (SA Fe-CDs) as a signaling carrier in collaboration with a DNA walker cascade amplification strategy triggered by nucleic acid exonuclease III (Exo III). The electrochemical active surface area of AuNPs/rGO modified onto a glassy carbon electrode (AuNPs/rGO/GCE) was about 1.43 times that of a bare electrode (bare GCE), with good electrical conductivity alongside a high heterogeneous electron transfer rate (5.81 × 10-3 cm s-1), that is, as well as the ability to load more molecules. Sequentially, the DNA walker cascade amplification strategy driven by Exo III effectively converted the target ctDNA into an amplified biosignal, ensuring the sensitivity and specificity of ctDNA. Ultimately, the electrochemical signal was further amplified by introducing SA Fe-CDs nanozymes, which could serve as catalysts for 3,3',5,5'-tetramethylbenzidine (TMB) oxidation with facile responding (Vmax = 0.854 × 10-6 M s-1) and robust annexation (Km = 0.0069 mM). The integration of the triple signal amplification approach achieved detection limits as low as 1.26 aM (S/N = 3) for a linearity spanning from 5 aM to 50 nM. In this regard, our proposal for a biosensor with exceptional assay properties in complicated serum environments had great potential for early and timely diagnosis of cancer.

A Coherent Pd–Pd16B3 Core–Shell Electrocatalyst for Controlled Hydrogenation in Nitrogen Reduction Reaction

AbstractThe manipulation of surface catalytic sites has rarely been explored for metal borides, and the subsurface effects on the electrocatalytic activity of the nitrogen reduction reaction (NRR) remain unknown. Herein, this work develops a core–shell nanoparticle catalyst with a Pd core that ensures high electron transfer rates and an Pd16B3 atomical shell that possess tunable active sites for regulating the NRR. The atomic structural evolution from Pd to Pd16B3 is investigated by precisely controlling the B atom diffusion, molecular rearrangement, and d–sp orbital hybridization. Pd/Pd16B3 core–shell nanocrystals exhibit an exceptional NRR performance with a high NH3 Faradaic efficiency of 30.8%, which is superior to those of pristine Pd (1.2%) and B‐doped Pd (4.8%) under identical conditions, and a yield rate of 0.81 µmol h−1 cm−2. This work discovers that the Pd16B3 shell could promote the NRR selectivity by separating the separating the hydrogen evolution reaction proceeded on hole sites and NRR proceeded on bridge sites, and the Pd core could provide the excellent conductivity to Pd16B3 shell through regulated electron interactions. Consequently, the controlled chemical ordering of palladium boride on palladium surfaces provides insight into the synthesis of advanced NRR electrocatalysts.

Air-gap-assisted solvothermal process to synthesize unprecedented graphene-like two-dimensional TiO2 nanosheets for Na+ electrosorption/desalination

Designing a high-performance capacitive deionization setup is limited due to the slow salt removal and charge storage capacities. Efforts are being made to replace traditional electrodes with advanced 2D materials. We introduce a simple method for synthesizing two-dimensional titanium dioxide graphene-like nanosheets via a unique air-gap-assisted solvothermal method. Crystalline 2D graphene-like anatase-TiO2 sheets of unprecedented quality were obtained by tuning the air gap in the solvothermal reactor. The 2D TiO2 synthesized by air-gap-assisted solvothermal process has shown an exceptionally high surface area of 934.5 m2/g compared to the pristine TiO2 (249.5 m2/g). The sheets were used as Faradaic electrodes in ion-electrosorption and their capacitive deionization capabilities were evaluated. The electrochemical conductivity was examined via an in situ investigation of Na+-ion migration and storage. The adsorption capacity of 2D TiO2 sheets increased with higher applied potential while keeping the adsorption time constant at 15 min. At adsorption potentials of –0.8 V, –1.0 V, and –1.2 V, desalting rates of 2.09, 2.18, and 2.20 mg g−1 min−1 resulted in adsorption capacities of 31.33, 32.73, and 33.023 mg g–1, respectively. The 2D TiO2 electrode demonstrated high electron-transfer rates, a large desalination capacity, and a rapid average desalting rate. The specific capacity of the 2D-layered TiO2 electrode was found to be about 45.68 F g−1. These results can be attributed to the large specific surface area, short ionic diffusion paths, numerous active adsorption sites, surface defects, and pseudocapacitance. This air-gap-assisted solvothermal method is expected to open new avenues for the synthesis of high-quality 2D materials.

Machine learning-based optimization of storage ring injection efficiency

Since the DELTA accelerator facility does not use a White circuit-driven fast topping-up mode, each software-driven injection ramp cycle takes about 7 seconds. Depending on the injection efficiency, 150 to 200 ramp cycles are required to reach the maximum beam current of 130 mA in the storage ring. Thus, for fast post-injection, a high electron transfer rate is crucial. During the injection process, a large number of parameters (e. g., magnet settings, timings of pulsed elements) have to be adjusted manually. The injection efficiency depends mainly on the settings of the booster extraction elements, the T2 transfer line magnets, and the storage ring injection components. In order to automate the injection procedure and to improve the electron transfer efficiency, the application of innovative machine learning concepts was studied.

On the performance of vertical MoS2 nanoflakes as a photoelectrochemical studies for energy application

With the help of a hydrothermal process, we were able to prepare vertically layered MoS2 nanoflakes that were rooted to TiO2 modified. MoS2 nanoflakes and TiO2 contribute significantly to the strong XRD peaks and μ-Raman spectroscopy, and this phenomenon may also be explained by the unique structure of vertically stacked MoS2 nanoflakes on TiO2 that has many exposed edges and large surfaces as well as high electron transfer rates between TiO2 and MoS2. As can be clearly seen, there are no noticeable changes in the self-photodegradation of MB under visible light interaction (VLI), and the MoS2 doped TiO2 photocatalyst displays ∼ 90 % degradation efficiency. By, measuring photoelectrochemically, charge carriers are separated efficiently. These experiments illustrate the transient photocurrent response of the MoS2 doped TiO2 photocatalyst while cycling between three on/off cycles. As a result of a low recombination rate of the photoexcited charge carriers, the MoS2 doped TiO2 photocatalyst displays superior photocurrent response. In other words, a lower charge transfer resistance results in a faster transfer of charge between the surfaces.

Confined PbO2 nanoparticles in carbon nanotubes on boron-doped diamond substrate for highly efficient chlortetracycline degradation

Realizing highly efficient catalysis with high stability in complex chemical environments remains a major challenge for advanced oxidation processes. Here, confined lead dioxide (PbO2) nanoparticles in carbon nanotubes (CNTs) on boron-doped diamond (BDD) substrate is designed and fabricated as a heterogeneous catalyst for antibiotic treatment, achieving ultra-efficient degradation of chlortetracycline (CTC) with high reaction rate and stability. The maximum degradation rate of CTC reaches 98.8 % in 120 min, and it remains 91.0 % after ten cycles, which are significantly higher than that proposed by the contrast catalysts. The excellent degradation performance of this heterogeneous catalyst is mainly attributed to three factors: (i) the prepared PbO2 nanoparticles with an average size of 5 nm are confined in CNTs, providing more active sites and higher electron transfer rate; (ii) secondary pollution and catalyst deactivation of PbO2 are avoided by protecting CNTs; (iii) BDD shows strong capacity for mineralizing organic compounds related to the high oxygen evolution reaction potential. This finding provides a novel strategy for advanced oxidation processes in environmental remediation.

Efficient scalable co-precipitated carbon dots and silver bromide doped manganese dioxide for catalytic and antimicrobial activity with evidential in-silico analysis

In this research, a co-precipitation approach was used to synthesize manganese oxide (MnO2) nanorods (NRs) doped with varying concentrations (2, 4 wt.%) of silver bromide (AgBr) and fixed amounts of carbon dots (CDs). CDs exhibit high photostability and a high electron transfer rate. AgBr can improve the activity of metal oxide owing to its electron-trapping effect. The new characteristics of as-prepared AgBr/CDs doped MnO2 NRs have a larger surface area, charge transport capabilities, and lower recombination chances, associating the synthesized material as a suitable choice for environmental cleanup. The removal of organic dye pollutants from wastewater and the elimination of harmful bacteria by the use of antibacterial activity were the goals of this research. The NRs demonstrated outstanding catalytic activity (CA) against rhodamine B (RhB) dye degradation. AgBr/CDs-doped MnO2 nanocatalyst indicates efficient dye degradation (96.39 %) in an acidic medium relative to other basic and neutral media. The fundamental components for generating reactive oxygen species (ROS) are electrons and hole pairs responsible for killing pathogenic bacteria. Compared to ciprofloxacin the substantial inhibition zones against Escherichia coli (E. coli) bacteria were measured at 2.95 mm. In silico molecular docking study of AgBr/CDs-doped MnO2 NRs proposed as promising DNA gyrase E. coli inhibitors.

Cobalt-doped Graphene-supported Nanoscale Zero-valent Iron: Removal of Rhodamine B solution and mechanistic study

nZVI materials loaded on GO have been applied to the treatment of difficult-to-degrade organics due to their higher electron transfer rate. However, cobalt doping of GO/nZVI composites and the effect of the doped materials on difficult-to-degrade organics are not known. In this work, Cobalt-doped Graphene-supported nanoscale Zero-valent Iron (GO/nZVI-Co) was successfully synthesized via the liquid-phase reduction-suspension self-assembly method, which was composited with theoretical mass ratio of GO:nZVI:Co = 1:2:0.08. And GO/nZVI-Co was used as efficient heterogeneous catalyst for degradation of Rhodamine B (RhB) via H2O2. Characterization results show that nZVI and Co particles were successfully loaded on GO nanosheets increasing the dispersibility of particles. Under the optimal reaction conditions(the mass ratio of GO: nZVI = 1:2 and Co doping is less than 1/5), the RhB degradation rate was as high as 98.28 %. The degradation pathways of GO/nZVI-Co-HP system could better explained by the secondary kinetic model and GC–MS spectru. The main effect of cobalt doping in the GO/nZVI-Co-HP system is to increase the adsorption properties of the material on H2O2, and this facilitates the contact reaction of nZVI with H2O2. In this study, a GO/nZVI-Co material with improved electron transfer efficiency was prepared and its removal mechanism of pollutants was elucidated to provide relevant theoretical support for the treatment of difficult-to-degrade wastewater.

NiS@CuBi2O4/ERGO heterostructured electro-catalyst for enhanced hydrogen evolution reaction

In this study, nickel sulfide (NiS)-decorated copper bismuthate/electro-reduced graphene oxide nanocomposites (NiS@CuBi2O4/ERGO) were fabricated on nickel foam (NF) electrodes by a two-step synthesis method including electrochemical deposition technique and thermally annealing. The prepared electrode materials were characterized using XRD, XPS, EDS, and SEM techniques. The NiS@CuBi2O4/ERGO electrode was used as a promising electrocatalyst for hydrogen evolution reaction (HER). The resulting electrode exhibited superb electrocatalytic activity, probably originating from more active sites and a higher electron transfer rate than the NF. HER activity of the electrode was investigated in 0.5 M H2SO4 solution and had an overpotential of 210 mV at the current density of 10 mA cm−2. Thanks to the NiS decoration, the HER stability of the thin films in the acidic environment has shown a remarkable improvement. Moreover, the electrocatalyst material, produced using a simple method, retained its activity by about ∼71% after stability tests at 100 mA cm−2.

The Linkage-Moderated Covalent Organic Frameworks with C=N and NN on Charge Transfer Kinetics Towards the Robust Photocatalytic Hydrogen Activity.

Since the linkages structured in covalent organic frameworks (COFs) usually impact the charge transfer behavior during photocatalytic hydrogen evolution reaction (pc-HER), linkage dependence on charge transfer kinetics should be further claimed. Herein, COFs with N-based linkages and pyrene-based building nodes are constructed to enable us to obtain new clues about the charge transfer behavior and evolution tendency relevant to linkages at a molecular level for pc-HER. It is demonstrated that photo-excited electrons preferably move to the N sites in C=N linkage for pc-HER and are trapped around NN linkage as well. A high electron transfer rate does not point to high photocatalytic activity directly, while a small difference between the electron transfer rate and electron recombination rate ΔkCT - CR predicts the inefficiency of charge transfer in Azod-COFs. Contrarily, large value of ΔkCT - CR in the case of Benzd-COFs, demonstrats an unimpeded charge transfer process to result in boosted pc-HER rate (2027.3 µmol h-1 g-1 ). This work offers a prominent strategy for the reasonable design of efficient photocatalysts at the molecular level for structural regulation and achieves an efficient charge transfer process for the pc-HER process.

Structural characterization and electrochemical performance of laser-induced graphene: Insights into electron transfer kinetics and 4-aminophenol sensing

Laser-induced graphene (LIG) is increasingly gaining importance as a 3D porous graphene material with outstanding properties. Here, LIG structures are realized for electrochemical sensors by patterning polyimide Kapton using a visible 405 nm laser under ambient conditions. The LIG electrodes for flexible electrochemical sensors show a large surface area with a hierarchical porosity distribution along the cross-section.To optimize the laser parameters, we investigated the electron transfer (ET) kinetics and the electrochemical performance of LIG surfaces produced with an exposure time varied from 10 ms to 50 ms. Characterization of the resulting LIG was performed to understand the correlation between the resulting electrochemical properties and the LIG surface properties by optical microscopy and Raman spectroscopy. The electrochemical properties were evaluated in ferri-ferrocyanide [Fe(CN)6]3−/4− by cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). The highest electron transfer rate constant was registered at an exposure time of 10 ms. However, for an exposure time of 20 ms, the electrochemical behavior is better due to both high surface area and high electron transfer rate constant.A voltammetric 4-Aminophenol sensor is developed as a proof-of-concept device. It exhibits a good analytical performance realizing a low limit of detection at a level of 9.23 nM in the concentration range from 10 nM to 400 nM. The results demonstrate the suitability of LIG for the development of efficient, disposable, and flexible electrochemical sensors. The developed technological approach supports sustainability while simplifying production and reducing costs.