Electrochemical water splitting stands as a promising method for harnessing energy from renewable sources. However, substantial overpotential required for sluggish oxygen evolution reaction (OER) ...hampers its widespread adoption. In this study, a CuSe@PPy hybrid is being created by hydrothermally layering polypyrrole on top of CuSe. This hybrid electrocatalyst outperforms both pure CuSe and PPy in terms of OER efficiency. Structural and morphological analyses, including powder X-ray diffraction, scanning electron microscopy, Fourier transform infrared spectroscopy, and Brunauer–Emmett–Teller (BET), confirm that the synthesized CuSe@PPy composite exhibits high crystallinity, nanostructured granular morphology, and a hexagonal structure with a large surface area. Evaluation of its electrocatalytic performance for water oxidation in a 1 M KOH alkaline medium reveals CuSe@PPy hybrid's exceptional durability, achieving 35 mA cm
−2
for 100 h. This durability is attributed to PPy coating on its surface, which facilitates efficient electron conduction. Coupling of PPy with CuSe leads to reduced overpotential (248 mV), a lower Tafel slope (30 mV/dec), and decreased charge transfer resistance (2.16 Ω), enhancing OER efficiency. By modifying surface of CuSe with a conducting polymer like PPy, this study underscores potential for improving performance in various applications, including photoelectron-catalytic research and stabilizing material activity.
The availability of hydrogen energy from water splitting through the electrocatalytic route is strongly dependent on the efficiency, durability, and cost of the electrocatalysts. Herein, a novel ...Bi2S3-covered Sm2O3 (Bi2S3–Sm2O3) nanocomposite electrocatalyst was developed by a hydrothermal route for the oxygen evolution reaction (OER). The electrochemical properties were studied in 1.00 mol KOH solution after coating the target material on the stainless-steel substrate (SS). Physical analysis via XRD, FTIR, IV, TEM/EDX, and XPS revealed that the Bi2S3–Sm2O3 composite possesses metallic surface states, thereby displaying unconventional electron dynamics and purity of phases. The Bi2S3–Sm2O3 composite shows outstanding OER activity with a low overpotential of 197 mV and a Tafel slope of 74 mV dec−1 at a 10 mA cm−2 current density as compared to pure Bi2S3 and Sm2O3. Meanwhile, the composite catalyst retains high stability even after 100 h of the chronoamperometry test. Thus, this work unveils a new avenue for the speedy flow of electrons, which is attributed to the synergetic effect between Bi2S3 and Sm2O3, as well as enriched interfacial defects, which exhibit greater oxygen adsorption capability with improved electronic assemblies in the active interfacial region. In addition, the introduced porous structure in core–shell Bi2S3–Sm2O3 provides extraordinary electrical properties. Thus, this article offers a realistic framework for electrochemical energy generation.
A simple approach to synthesizing tin selenide nanostructures showing superior photocatalytic performance with variable tin ratios
via
a facile chemical method is reported in this study. The ...crystalline phase, morphology, oxidation states of elements, surface composition and optical properties of the photocatalysts were investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), and UV-vis spectroscopy, respectively. The photocatalytic activity was evaluated by the degradation of methylene blue (MB) under visible-light irradiation, indicating that SnSe exhibits excellent photocatalytic performance with a maximum % degradation efficiency of MB up to 92.91% after 40 min of light irradiation. These materials were also used as photocatalysts for the degradation of Congo red (CR) and the results showed 98% degradation of Congo red which is much higher than other photocatalysts. The possible degradation pathway is also presented. Indeed, SnSe nanostructures with variable tin ratios behaved as highly efficient photocatalysts and could be promising for future industrial applications for wastewater treatment.
Photocatalytic activity and proposed reaction mechanism of degradation of Methylene Blue dye by SnSe nanostructures.
A series of hierarchical flower-like magnesium oxide (MgO) microspheres were prepared with an ethylene glycol (EG)-assisted route at room temperature using ammonia as a precipitating agent. Effects ...of the ethylene glycol (EG) ratio on the structure, morphology and pore properties were carefully investigated. The hierarchical porous MgO microsphere exhibited a surface area of 75 m
2
g
−1
and total pore area of 47.37 m
2
g
−1
at the highest ratio of EG (EG/Mg
2+
= 10) in the reaction system. The prepared MgO microspheres exhibited an outstanding removal capacity of 574.71 mg g
−1
for phosphate following the pseudo second order kinetic model (
R
2
= 0.99) and Langmuir isotherm model with the endothermic nature of phosphate adsorption which resulted from the high surface area and suitable pore size. Both the isothermal parameter
R
L
between 0 and 1 and the negative the Gibbs free energy value suggested that phosphate adsorption on a MgO microsphere was a favorable process. Undoubtedly, this template-free mild synthesis method effectively promotes wide practical applications and mass scale production of porous MgO microsphere adsorption material.
Hierarchical porous flower-like MgO microspheres were fabricated
via
an ethylene glycol-assisted route under mild conditions and exhibited an outstanding maximum adsorption capacity of 574.71 mg g
−1
for phosphate.
Electrocatalytic water splitting is an essential hydrogen production method for resolving present energy shortage and progress toward more efficient technologies. For this purpose, a versatile and ...cheap electrocatalysts are the main challenge along the way. In this report, we synthesized vanadium telluride and carbon nanotube (VTe–CNT)‐based nanocomposite via facile hydrothermal route. The VTe–CNTs are characterized by X‐ray diffraction analysis, scanning electron microscopy, energy‐dispersive spectroscopy, Fourier transform infrared spectroscopy, and Brunauer–Emmett–Teller. These characterizations depict nanosphere structures, morphology, and high surface area that maintains high porosity, which are essential for inclusive water‐splitting phenomena in 1.0 M solution of KOH. Additionally, the electrochemical performance of VTe–CNTs has shown best O2 evolution reactions activity with of onset potential of 1.42 V versus reversible hydrogen electrode and required 10 mA/cm2 of current density at 278 mV overpotential, which is excellent among other electrocatalysts, VTe (342 mV@10 mA/cm−2) and CNTs (365 mV@10mA/cm−2). Moreover, VTe–CNT exhibits remarkable stability for almost 20 h. It also requires a low onset potential of 0.05 V with a small Tafel slope of 47 mV/dec for H2 evolution reactions. Hence, this research might facilitate the easy transportation of electrons and open up the new era, serving as an excellent replacement for noble metal–derived materials.
Nowadays, water pollution and energy crises worldwide force researchers to develop multi-functional and highly efficient nanomaterials. In this scenario, the present work reports a dual-functional ...La2O3–C60 nanocomposite fabricated by a simple solution method. The grown nanomaterial worked as an efficient photocatalyst and proficient electrode material for supercapacitors. The physical and electrochemical properties were studied by state-of-the-art techniques. XRD, Raman spectroscopy, and FTIR spectroscopy confirmed the formation of the La2O3–C60 nanocomposite with TEM nano-graphs, and EDX mapping exhibits the loading of C60 on La2O3 particles. XPS confirmed the presence of varying oxidation states of La3+/La2+. The electrochemical capacitive properties were tested by CV, EIS, GCD, ECSA, and LSV, which indicated that the La2O3–C60 nanocomposite can be effectively used as an electrode material for durable and efficient supercapacitors. The photocatalytic test using methylene blue (MB) dye revealed the complete photodegradation of the MB dye under UV light irradiation after 30 min by a La2O3–C60 catalyst with a reusability up to 7 cycles. The lower energy bandgap, presence of deep-level emissions, and lower recombination rate of photoinduced charge carriers in the La2O3–C60 nanocomposite than those of bare La2O3 are responsible for enhanced photocatalytic activity with low-power UV irradiation. The fabrication of multi-functional and highly efficient electrode materials and photocatalysts such as La2O3–C60 nanocomposites is beneficial for the energy industry and environmental remediation applications.
Graphene oxide based electrode materials show remarkable electrochemical properties due to the improved specific surface area and electrical conductivity for supercapacitor applications. ...Hydrothermally synthesized graphene oxide based aluminum sulfide nanowalls on nickel foam (NF) have revealed excellent pseudocapacitive behavior with the specific capacitance 2362.15 F g-1 at 2 mVs-1 as observed through cyclic voltammetry. The galvanostatic charge-discharge measurements confirmed a specific capacitance 2373.51 F g-1 at 3 mAcm−2. Hexagonal phase of the graphene oxide (GO) based Al2S3 nanowalls also showed good discharge time of 820 s and energy density 118.68 WhKg−1 at 3 mAcm−2. Moreover, the fabricated electrode material exhibited good power density 2663.58 W kg-1 at 20 mAcm−2. The impedance results also confirmed the pseudocapacitive characteristics and revealed weak contact and Warburg resistances for the electrode material in half cell. Hence, GO based Al2S3 nanowalls performed as a prominent electrode material for asymmetric supercapacitors. Additionally, electrode material also exhibited excellent symmetric behavior, which again suggested a good electrode structure for supercapacitor applications.
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•GO based Al2S3 nanowalls showed excellent pseudo capacitance of 2362.15 F g-1.•GO based Al2S3 nanowalls revealed Pd of 2663.58 W kg-1 at current density 20 mAcm−2.•GO based Al2S3 nanowalls showed high Csp (2373.51 F g-1) and Ed (118.68 WhKg−1).•GO based Al2S3 nanowalls showed good symmetric behavior with Ed of 20.55 WhKg−1.•GO based Al2S3 nanowalls is suitable for symmetric and asymmetric supercapacitors.
State of the art developments of the supercapacitor applications of nitrogenous MOFs are summarized and their future prospects are sketched out.
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•Coordination chemistry of nitrogenous ...MOFs is reviewed for applications.•Nitrogenous MOFs and their composites can act as better electrode materials for supercapacitors.•The state of the art developments of nitrogenous MOFs/composites are described.•Future outlook is also given to further the chemistry of nitrogenous MOFs.
The unsatisfactory performance of energy-storage devices often stymies future advancements in a broad spectrum of industries, including portable gadgets, transportation, and green energy. By taking advantage of porous crystalline materials, a novel class of materials i.e., metal–organic framework (MOF) has perceived a remarkable upsurge of attention in versatile applications since their birth. Among MOFs, nitrogenous MOFs (self-assembled metal ions/clusters by nitrogen-containing organic ligands) are considered as one of the most promising electrode materials for supercapacitor applications owing to their ultrahigh specific surface area (SSA), wide pore-size distribution, adjustable crystal structure and morphology, open metal sites, and high self-doped nitrogen content. Indeed, nitrogenous MOFs and their derivatives and composite materials exhibit diverse structures, relatively high conductivity, excellent electrochemical performances, and stability. Despite their excellent features and extensive research, there has been no critical review reported solely focusing on nitrogenous MOF, their derivative and composite materials applied in supercapacitors. This review firstly discusses the comprehensive introduction, types and charge storage mechanism of supercapacitors, and the effect of nitrogen on the physicochemical properties. Followed by the well-known synthesis methods, the effect of dimensionality and morphology of MOFs on electrochemical performance and stability has been critically discussed. Then, the latest advancements in nitrogenous mono-and mixed-metallic MOFs and their derivative and composite materials have been explored in terms of their basically required characteristics including chemical composition, surface area, nitrogen content, porous structure, and tunable morphologies in supercapacitors. Finally, based on a comprehensive understanding of recent advancements, underlying challenges, guidelines, and perspectives on boosting the electrochemical performance of nitrogenous MOF materials for next-generation supercapacitors have also been documented.
Water electrolysis is a propitious strategy to overcome the exceeding energy crisis by producing renewable and green hydrogen fuel. However, the practical application of this process is limited due ...to the inadequacy of earth-rich, economical, and efficient electrocatalysts for carrying out kinetically more sluggish oxygen evolution reactions (OER). In the present research, a simple sol–gel method was employed to produce Co
3
O
4
/Pr
2
O
3
nanocomposite material, which provides exceptional electrical conductivity and lesser charge transfer resistance of mixed-valence cations. The fabricated nanomaterials were analyzed using various scientific techniques, including X-ray diffraction (XRD), scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HR-TEM), and energy dispersive X-ray spectroscopy (EDX) to determine their crystal structure, morphology, elemental composition, and oxidation states. To investigate the water oxidation capability and steadiness of the modified Co
3
O
4
/Pr
2
O
3
electrode material in alkaline conditions, cyclic voltammetry (CV), linear sweep voltammetry (LSV), and constant current chronoamperometry (CA) were utilized. These outcomes revealed that the resultant nanocomposite exhibits a minimal overpotential around 257 mV and a lower Tafel slope around 78 mVdec
−1
at a benchmark current density of 10 mAcm
−2
. In addition, the alkaline solution reliability of the electrocatalysts was examined and confirmed to be steady for 24 h via chronoamperometry. The extraordinary electrocatalytic achievement of Co
3
O
4
/Pr
2
O
3
is ascribed to its structural synergistic effect, which encourages the oxygen evolution activity.
The development of a proficient and ultra-high sensitive functionalized electrode for accurate analysis of drugs is a long-standing challenge. Herein, we report an electrochemical nanocomposite ...scaffold, comprising of silver nanoparticles integrated with functionalized carbon nanotubes (COOH-CNTs/Ag/NH
2
-CNTs) for the simultaneous quantification of two widely used amlodipine (AM) and atorvastatin (AT) drugs. The sandwiched nanocomposite materials were thoroughly characterized morphologically and structurally. The nanocomposite COOH-CNTs/Ag/NH
2
-CNTs immobilized over glassy carbon electrode catalyzed electron transfer reactions at the electrode-electrolyte interface and facilitated detection of targeted drugs, as revealed by the significant decrease in oxidation potentials at 879 mV and 1040 mV and improved current signals. Electrochemical characterization and testing show that the functionalized porous architecture with a large effective surface area is a promising scaffold for the sensing of a binary mixture of AM and AT with limits of detection in the femtomolar range (77.6 fM, and 83.2 fM, respectively). Besides, the specificity, stability, and reliability of the electrochemical sensing platform in simple and complex biological and pharmaceutical samples with high percentage recoveries highlight its scope for practical applications. Computational studies supported the experimental outcomes and offered insights about the role of modifier in facilitating electron transfer between transducer and analytes.
Development of an ultra-sensitive electrochemical platform for the simultaneous detection of two high blood pressure drugs.
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