Publications

Developing efficient water-splitting electrocatalysts, particularly for the anodic oxygen evolution reaction (OER), is an important challenge in energy conversion technologies. In this study, we report the development of iron-doped nickel disulfide nanoarray on Ti mesh (Fe0.1-NiS2 NA/Ti) via the sulfidation of its nickel–iron-layered double hydroxide precursor (NiFe-LDH NA/Ti). As a three-dimensional OER anode, Fe0.1-NiS2 NA/Ti exhibits remarkable activity and stability in 1.0 M KOH, with the requirement of a low overpotential of 231 mV to achieve 100 mA·cm−2. In addition, it exhibits excellent activity and durability in 30 wt.% KOH. Notably, this electrode is also efficient for the cathodic hydrogen evolution reaction under alkaline conditions.

The corrosion issue with acidic and alkaline water electrolyzers can be avoided by developing water oxidation catalysts performing efficiently under benign conditions. In this Letter, we report that a NiFe-borate layer can be generated on a NiFe-layered double hydroxide nanosheet array hydrothermally grown on carbon cloth via an in situ electrochemical surface derivation process in potassium borate (K-B_i) solution. The resulting 3D NiFe-LDH@NiFe-B_i nanoarray (NiFe-LDH@NiFe-B_i/CC) demonstrates high activity for water oxidation, demanding overpotentials of 444 and 363 mV to achieve 10 mA cm^-2 in 0.1 and 0.5 M K-B_i (pH: 9.2), respectively, rivaling the performances of most reported non-noble-metal catalysts in near-neutral media. Notably, this electrode also shows strong electrochemical durability with a high turnover frequency of 0.54 mol O₂ s^-1 at overpotential of 600 mV. All these features promise its use as an efficient earth-abundant catalyst material for water oxidation under eco-friendly conditions.

In this Letter, we report the development of hierarchical CoTe2 nanowire array on Ti mesh (CoTe2 NA/TM) via topotactical conversion from its Co(OH)F precursor through hydrothermal tellurization reaction. As a 3D oxygen evolution electrocatalyst, such CoTe2 NA/TM exhibits excellent catalytic activity with an overpotential of 340 mV to attain 50 mA cm–2 in 1.0 M KOH. Notably, it also exhibits high durability for 25 h.

In this communication, we demonstrate that a nickel cobalt sulfide nanosheet film electrodeposited on a titanium mesh (Ni-Co-S/TM) exhibits high catalytic activity toward electrooxidation of glucose. As a nonenzymatic glucose sensor, this Ni-Co-S/TM catalyst electrode shows a wide linear response range of 0.001-3 mM, a low limit of detection of 0.12 μM with a signal-to-noise ratio of 3, a sensitivity of 3291.5 μA mM^-1 cm^-2, and a fast response time of less than 5 s. Moreover, it also demonstrates high selectivity, good reproducibility and long-term stability for glucose detection.

This work has developed a facile strategy to create magnetically separable, core‐shell structured composites consisting of a magnetic Ag nanowires (NWs)/Fe 3 O 4 cores and an outer mesoporous TiO 2 (mTiO 2 ) shell using a sol–gel process and subsequent hydrothermal treatment. Benefiting from the mesoporous anatase TiO 2 as well as the unique structures of the composite, the resulting Ag NWs/Fe 3 O 4 @mTiO 2 composite was employed as a catalyst for removal of the organic contaminants through a colorimetric photocatalytic degradation assay using methylene blue (MB) as a model contaminant. Moreover, the photocatalysts can be easily separated and recycled with an external magnetic field and possess prominent recoverability.

Water pollution is considered a perilous issue that requires an immediate solution. This is largely because of the strong correlation between the global population increase and the amount of waste produced (most notably food waste). This project prompts the conversion of food waste into useful materials that can be used with sodium alginate as a catalytic support for metal nanoparticles. Sodium alginate/banana peel (Alg/BP) beads were prepared simply using an eco-friendly method. The prepared materials were modified using nanostructured materials to enhance their characteristics. Alg/BP beads were employed as adsorbents for metals that were then treated with sodium borohydride to produce MNPs@Alg/BP. Different MNPs@Alg/BP (MNPs = Ag, Ni, Co, Fe, and Cu) were used as catalysts for reducing 4-nitrophenol (4-NP) by NaBH₄ to evaluate each catalyst performance in a model reaction. The results exhibited that Cu@Alg/BP was most efficient toward complete transformation of 4-NP. Therefore, Cu@Alg/BP was also used as a catalyst for the reduction of potassium ferricyanide, congo red, methyl orange (MO), and methylene blue. It was found that Cu@Alg/BP beads catalytically reduced up to 95-99% of above pollutants within a few minutes. Cu@Alg/BP beads were more selective in reducing MO among the pollutants. The catalytic activity of Cu@Alg/BP was examined by evaluating the impact of numerous parameters on MO reduction. The results are expected to provide a new strategy for the removal of inorganic and organic water contaminants based on efficient and low-cost catalysts.

The hybridization of plant cellulose fillers in polymeric laminates is applied in different applications because of several benefits. The present investigation deals with the fabrication of four other eight-layer laminates by reinforcing bio fillers (coir, sisal, and hemp), Titanium carbide (TiC) nanoparticles, and ranging the stacking sequence of synthetic fabrics (carbon, Kevlar, Basalt, and Innegra) with bio/synthetic epoxy from wet layup technique. The fabricated laminate's characteristics were appraised by examining density, porosity, water absorption, flexural, impact strength, shore hardness, and thermal stability. It was observed from the experimental outcomes that the 3F8LTSE (Sisal, hemp, coir fillers, 2 layers of Carbon, Kevlar, Basalt, Innegra fabrics, and Titanium carbide reinforced synthetic epoxy) composite exhibited higher mechanical characteristics with a higher flexural strength (312.58 MPa), impact strength (35.13 kJ/m2), and shore D hardness (84.95), and decreased water absorption capacity by justifying its adequate for lightweight structures. The scanning electron microscope displayed the fiber pull out, debonding, and dispersion of fillers within the matrix of the composite. The current study also evaluates the prediction and performance of the artificial neural network (ANN) to model the physical, mechanical and thermal characteristics of bio/synthetic epoxy hybrid composites. However, the ANN model was more precise and proved that it is a primary method to optimize the properties of the fabricated bio/synthetic epoxy laminate.

Exploitation of efficient and earth-abundant electrocatalysts for the oxygen evolution reaction (OER) is of great importance. Herein, we report that the formation of an amorphous Mn-Co-P shell on MnCo₂O₄ can boost its OER activity in alkaline media. The core-shell Mn-Co-P@MnCo₂O₄ nanowire array on Ti mesh (Mn-Co-P@MnCo₂O₄/Ti) shows excellent electrochemical catalytic activity and requires an overpotential of 269 mV to drive 10 mA cm^-2 in 1.0 M KOH, which is 93 mV less than that for the MnCo₂O₄ nanoarray. Notably, this catalyst also shows strong long-term electrochemical durability with its activity being maintained for at least 100 h and achieves a high turnover frequency of 1.06 s^-1 at an overpotential of 450 mV.