International Journal of Pure and Applied Chemistry

Electrochemical Reduction of Carbon Dioxide to Formate by Tin-based Metal-Organic Frameworks

Austin Chipojola Mtukula, PhD, Wen-Chuan Lai, PhD, Zhi-Yuan Gu, PhD — Sun, 02 Mar 2025 19:28:32 +0200

There is an urgent need to develop new technologies for converting greenhouse gas CO2 into useful products to address environmental and energy crises simultaneously. Electrochemical CO2 reduction reaction (eCO2RR) driven by renewable electricity affords a capable route to realizing a carbon-neutral future and combating a global climate predicament. In determining the relationship between synthesis approach, catalyst structure and performance, two Sn-MOF electrocatalysts were produced with a bottom-up hydrothermal method. A two-dimensional catalyst 2D Sn-BDC was prepared by the open hydrothermal synthesis method, while a three-dimensional catalyst 3D Sn-BDC was prepared under the closed hydrothermal method. In CO2-saturated 0.5 M KHCO3 aqueous solution, 2D Sn-BDC catalyst displayed good performance compared with 3D Sn-BDC catalyst for CO2 reduction to formate with Faradaic efficiency of 96.3 %, partial current density of 10.0 mA cm-2 at an overpotential of 0.42 V, TOF of 4887 h-1, charge transfer resistance of 42.98 Ω and over a 10 h stability. It is recognized that the superiority of 2D Sn-BDC is assumed to originate from the ultrathin structure, enhanced surface area and presence of surface vacancies. Consequently, the improvement in mass transport, accessibility of Sn active sites and carrier concentration resulted in high catalytic performance

Comparative Effects of Wood Ash and Calcium Carbonate on the Physicochemical Properties of Soils

Mon, 28 Apr 2025 16:14:44 +0200

Soil acidity is one of the soil degradation problems that affects the productivity of soils in Cameroon and Awing in particular and this has led to a steady decline in crop yields in such acid soils. This research aimed to evaluate the effects of two liming materials (wood ash and calcium carbonate) on the physicochemical properties of volcanic-influenced soils of Meupi-Awing, Northwest Cameroon. Two surface soil samples (0–30 cm) were collected and analysed for physicochemical properties before liming. Twenty-four sub-samples (six samples each) were limed separately with wood ash and calcium carbonate respectively for 3 and 6 weeks in a greenhouse incubator in the field and analysed for some physicochemical properties using international standard methods. Correlation analyses were done using SPSS version 20. The effects of liming materials on the soil physicochemical properties showed an increase in pH (from 5.0 to 9.1), electrical conductivity (from 0.03 to 0.60 mS/cm), sum of exchangeable bases (from 7.01 to 48.53 cmolc/kg), available phosphorus (from 5.81 to 86.11 mg/kg) and a decrease in the exchangeable acidity (from 0.26 to 0.00 cmolc/kg). Between the two liming materials, wood ash was generally more effective than calcium carbonate in the amelioration of soil properties, even though the differences were not significant (p > 0.05). This may be due to the fact that wood ash is natural lime that is rich in bases whereas CaCO₃ contains only the Ca²⁺ and CO₃²- ions. Liming of these soils enhances the availability of nutrient anions and cations for plant uptake while trace elements reported in the study area are decreased from toxic to normal levels since their solubility in the soils is reduced at higher soil pH, hence reducing soil pollution. A minimum lime application rate of 2.70 g/kg soil for calcium carbonate and 7.72 g/kg soil for wood ash is recommended in the study area and in other areas with similar soil types

Punica Granatum Leave Extract as Green Corrosion Inhibitor for Mild Steel in Hydrochloric Acid

Ahmed Ali Adan, Abdinasir Hassan Mohamed — Thu, 03 Jul 2025 20:23:19 +0200

Corrosion is a significant issue that has resulted in the expenditure of millions of dollars by businesses worldwide for the restoration of machinery and structures. An environmentally benign corrosion inhibitor derived from Punica granatum leaves was employed in this investigation. The objectives of this study were to evaluate the effectiveness of Punica granatum leaf extraction as a corrosion inhibitor of mild steel in a hydrochloric acid solution. In this paper, we used mild steel as the sample and 1M hydrochloric acid as the acid solution. This research involved two tests: scanning electron microscopic studies and energy dispersive spectroscopy. In order to enhance the mild steel specimen’s characterisation, scanning electron microscopy and energy dispersive spectroscopy will be implemented for surface examination. We removed and dried the specimens after 72 hours. Comparing the specimens that were immersed in PGLE inhibitor solutions to those that were immersed in 1M HCl alone, scanning electron microscopic studies (SEM) images showed that the specimens that were immersed in the PGLE inhibitor solutions were in better shape and had smoother surfaces. Energy dispersive spectroscopy (EDX) was used to find out what the mild steel sample's surface was made of when inhibitors were present and when they were not present in the 1M HCl solution. To calculate the corrosion efficiency (Ƞw%), we measured the weight loss of mild steel in uninhibited and inhibited solutions after 3, 6, and 9 days. Finally, the results demonstrate that Punica granatum leaves reduce the rate of corrosion on mild steel or other metals