Electrochemical Enhancement of Binary CuSe2@MoSe2 Composite Nanorods for Supercapacitor Application

Structural-morphological insights into optimization of hydrothermally synthesized MoSe2 nanoflowers for improving supercapacitor applications

The present work reports a clear and improved hydrothermal methodology for the synthesis of MoSe2 nanoflowers (MNFs) at 210 °C. To observe the effect of temperature on the fascinating properties, the process temperature was modified by ±10 °C. The as-prepared MNFs were found to consist of 2D nanosheets, which assembled into a 3D flower-like hierarchical morphology via van der Waals forces. The elemental composition and mapping of the MNFs reveal that the constituents are uniformly distributed throughout the material. Crystallographic and structural analyses confirmed that the as-synthesized MNFs were of a highly crystalline nature with a two-layer hexagonal (2H) phase of MoSe2 (2H-MoSe2). Additionally, the microstructure and lattice-scale features of the MNFs studied using HRTEM disclosed ultrathin nanosheets of thickness ∼3 nm, which were a few atomic layers thick. A plausible formation and growth mechanism of the as-prepared MNFs is also proposed. For the purpose of developing supercapacitors, the electrochemical energy storage characteristics of the synthesized MNFs were examined. Maximum specific capacitance of 284.8 F g-1 at 5 mV s-1 scan rate was demonstrated by the three-electrode setup, and the capacitance retention was about 88%, even after 10 000 cycles. As an electrode material for supercapacitors, MNFs have great potential due to their high specific capacitance and exceptional cycling stability.

A comprehensive review on MoSe2 nanostructures with an overview of machine learning techniques for supercapacitor applications

In the past few decades, supercapacitors (SCs) have emerged as good and reliable energy storage devices due to their impressive power density, better charge-discharge rates, and high cycling stability. The main components of a supercapacitor are its electrode design and composition. Many compositions are tested for electrode preparations, which can provide good performance. Still, research is widely progressing in developing optimum high-performance electrodes. Metal chalcogenides have recently gained a lot of interest for application in supercapacitors due to their intriguing physical and chemical properties, unique crystal structures, tuneable interlayer spacings, broad oxidation states, etc. MoSe2, belonging to the family of Transition Metal Dichalcogenides (TMDs), has also been well explored recently for application in supercapacitors due to its similar properties to 2D materials. In this review, we briefly discuss supercapacitors and their classification. Various available synthesis routes for MoSe2 preparation are summarized. A detailed assessment of the electrochemical performances of different MoSe2 composites, including cyclic voltammetry (CV) analysis and galvanostatic charge-discharge (GCD) analysis, is given for symmetric and asymmetric supercapacitors. The limitations of MoSe2 and its composites are mentioned briefly. The use of machine learning methods and algorithms for supercapacitor applications is discussed for forecasting valuable details. Finally, a summary is provided, along with conclusions.

Electrochemical Detection of Melphalan in Biological Fluids Using a g-C3N4@ND-COOH@MoSe2 Modified Electrode Complemented by Molecular Docking Studies with Cellular Tumor Antigen P53

Melphalan (Mel) is a potent alkylating agent utilized in chemotherapy treatments for a diverse range of malignancies. The need for its accurate and timely detection in pharmaceutical preparations and biological samples is paramount to ensure optimized therapeutic efficacy and to monitor treatment progression. To address this critical need, our study introduced a cutting-edge electrochemical sensor. This device boasts a uniquely modified electrode crafted from graphitic carbon nitride (g-C3N4), decorated with activated nanodiamonds (ND-COOH) and molybdenum diselenide (MoSe2), and specifically designed to detect Mel with unparalleled precision. Our rigorous testing employed advanced techniques such as cyclic voltammetry and differential pulse voltammetry. The outcomes were promising; the sensor consistently exhibited a linear response in the range of 0.5 to 12.5 μM. Even more impressively, the detection threshold was as low as 0.03 μM, highlighting its sensitivity. To further enhance our understanding of Mel's biological interactions, we turned to molecular docking studies. These studies primarily focused on Mel's interaction dynamics with the cellular tumor antigen P53, revealing a binding affinity of -5.0 kcal/mol. A fascinating observation was made when Mel was covalently conjugated with nanodiamond-COOH (ND-COOH). This conjugation resulted in a binding affinity that surged to -10.9 kcal/mol, clearly underscoring our sensor's superior detection capabilities. This observation also reinforced the wisdom behind incorporating ND-COOH in our electrode design. In conclusion, our sensor not only stands out in terms of sensitivity but also excels in selectivity and accuracy. By bridging electrochemical sensing with computational insights, our study illuminates Mel's intricate behavior, driving advancements in sensor technology and potentially revolutionizing cancer therapeutic strategies.

Carbon quantum dots modified and Y3+ doped Ni3(NO3)2(OH)4 nanospheres with excellent battery-like supercapacitor performance

Supercapacitor is an important energy storage device widely used in the automobile industry, military production, and communication equipment because of its fast charge-discharge rate, and high power density. Herein, carbon quantum dots modified and Y3+ doped Ni3(NO3)2(OH)4 (NiY@CQDs) nanospheres are prepared by a solvothermal method and used as an electrode material. The electrochemical properties of NiY@CQDs were measured in a three-electrode system. An asymmetric supercapacitor (ASC) cell was assembled with activated carbon (AC) as the anode and NiY@CQDs as the cathode. The electrochemical properties of the ASC device were measured in a two-electrode system. Experimental results show the shape of NiY@CQDs is petal-shaped and the introducing carbon quantum dots and doping Y3+ significantly increases the specific surface area, conductivity, and specific capacitance of Ni3(NO3)2(OH)4. The mass-specific capacitance of NiY@CQDs reaches up to 2944 F g-1 at a current density of 1 A g-1. The asymmetric supercapacitor of NiY@CQDs//AC has a high energy density of 138.65 Wh kg-1 at a power density of 1500 W kg-1, displaying a wide range of application prospects in the energy storage area.