RESUMEN
Conventional energy resources are diminishing, and environmental pollution is constantly increasing because of the excessive use of fossil fuels to sustain the ever-increasing population and industrialization. This has raised concerns regarding a sustainable future. In the pursuit of addressing sustainability in industrial processes and energy systems, the production of green hydrogen is considered a promising and crucial solution to meet the growing energy demands. Water-splitting is one of the most effective technologies for producing clean and carbon-neutral hydrogen. Water-splitting is a scientifically emerging application, but it is commercially limited due to its economic non-viability. The sluggish kinetics and the high overpotential needed for the water-splitting reactions (HER and OER) have encouraged the scientific community to design electrocatalysts that address the concerns of low activity, efficiency and stability. Designing a hybrid catalyst using metal-organic frameworks (MOFs) with transition metal carbides can be a suitable approach to address the deficiencies of conventional water-splitting catalysts. In this study, we have designed and fabricated an electrocatalyst of tungsten carbide (WC) with two different MOFs (Zr-based and Fe-based) and explored their electrocatalytic activity for hydrogen generation in an alkaline medium. It should be noted that hybrids of tungsten carbide with a zirconia MOF (UiO-66) showed better electrocatalytic activity with low overpotentials of 104 mV (HER) and 152 mV (OER) at a current density of 10 mA cm-2. This superior activity of WC with the Zr-MOF in comparison to the Fe-MOF is due to the synergistic effect of Zr present in UiO-66 grown on the WC matrix. Moreover, UiO-66 provides a larger electrocatalytic active surface area, so available active sites are more in UiO-66 as compared to the Fe-MOF. These findings set the stage for the systematic development and production of bi-functional hybrid catalysts with the potential to be utilized in water-splitting processes.
RESUMEN
Drilling fluids are an essential component of drilling operations in the oil and gas industry. Nanotechnology is being used to develop advanced drilling fluid additives. This study looked at the viability of synthesizing SiO2/g-C3N4 hybrid extending the Stober process followed by its addition in different concentrations to water-based drilling fluids and studying impact on the rheological and fluid loss properties of the fluids. The synthesized hybrid was analyzed using XRD, SEM, TGA, and FTIR. Subsequently, it was used to develop the water-based drilling mud formulations and subjected to measurements in accordance with API standard practices. The studies were carried out at various SiO2/g-C3N4 nanoparticle concentrations under before hot rolling (BHR) and after hot rolling (AHR) conditions. The outcomes demonstrated that the rheological and fluid loss properties were enhanced by the addition of SiO2/g-C3N4 nanoparticles, as it worked in synergy with other additives. Additionally, it was discovered that the nanoparticles improved the drilling fluid thermal stability. The experimental findings indicate a significant influence of SiO2/g-C3N4 nanoparticles on base fluid properties including rheology and fluid loss as the most remarkable, especially at higher temperatures. The significant improvements in yield point and 10 s gel strength were 55 and 42.8% under BHR and 216 and 140% under AHR conditions, respectively. Permeability plugging test (PPT) fluid loss was reduced by 69.6 and 87.2% under BHR and AHR conditions, respectively, when 0.5 lb/bbl nanoparticles were used in formulations. As a result, SiO2/g-C3N4 nanomaterial has the potential to be used as drilling fluid additive in water-based drilling fluids.
RESUMEN
Environmental degradation and energy constraint are important risks to long-term sustainability in the modern world. Water splitting is a vital approach for environmentally friendly and sustainable energy storage, providing a clean way to produce hydrogen without pollutants. Preparing a catalyst that is active, bifunctional, and durable for water splitting is a difficult task. We addressed the difficulty by creating a bifunctional heterogeneous catalyst, MoS2/rGO, with an ideal weight percentage of 5 wt% by a hydrothermal process. The optimized sample showed exceptional electrocatalytic activity, requiring an overpotential of 242 mV and 120 mV to achieve a current density of 10 mA cm-2 in the Hydrogen Evolution Reaction (HER) and Oxygen Evolution Reaction (OER). Furthermore, our synthesized catalyst was validated for its exceptional water-splitting capacity, with the optimized sample showing low Tafel slope values of 59 mV dec-1 for HER and 171 mV dec-1 for OER. The significant OER and HER activity seen in the 5 wt% MoS2/rGO hybrid, compared to other hybrids, is due to the many catalytic active sites that aid in charge and electron transport, as well as the synergistic interaction between MoS2 and rGO.
RESUMEN
A number of coating techniques have been used to improve the processability of high explosives. These techniques are typically used for developing compositions, such as boosters and fillers. The most typically used technique is the "solvent-slurry coating". Several compositions of polymer-bonded explosives have been industrialized using this technique. The NUPC-6 polymer-bonded powder composition of hexahydro-1,3,5-trinitro-1,3,5-triazine is optimized using the solvent-slurry coating. It involved multiple processes, i.e., preparing a slurry of high explosives in an aqueous phase, dissolving the modified polymer binder in an organic solvent, maintaining both the solvent and slurry at controlled temperatures, introducing polymer binder solution and ingredients in the slurry, distilling the solvent, mixing contents homogeneously, filtering the polymer-coated hexahydro-1,3,5-trinitro-1,3,5-triazine composition, and drying in a vacuum oven. The phlegmatizing and hydrophobic agents enhance flowability and hydrophobicity. The mass flow rate, bulk density, tapped density, compressibility index, and Hausner ratio are determined to evaluate its flowability during filling operations. The results show that the composition is flowable using a filling funnel, with a 150 mm upper diameter, 25 mm flow diameter, and 136 mm total funnel height. The raw polymer binder was modified using diisooctylsebacate and SAE-10 oil. The additives in the composition enhance its flowability, and it might be used in underwater applications.