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Cellular Lightweight Concrete (CLC) with the addition of Few Layers Graphene (FLG) has been fabricated and characterized for canal blocks application. The CLC-FLG composite was made by mixing fine agregate (sand), cement, fly ash, water, and FLG. The compressive strength properties of the composite was tested using a digital compressive strength test to determine the effects of FLG addition, sand size gradations, and environmental acidity on the compressive strength of the composite. Meanwhile, the composite morphology was examined using Scanning Electron Microscopy (SEM). The increase in FLG content and concentrations increased the compressive strength. The highest compressive strength was shown by the composite with the highest FLG addition (15%) and without sand size gradation, namely 5.19 Mpa or there was an increase of 15.6% compared to CLC without the addition of FLG. The level of water acidity relatively did not affected the compressive strength of CLC-FLG composite. Morphological analysis showed that the addition of FLG resulted in a denser structure and reduced porosity of CLC. The CLC-FLG composite can be used as canal blocks materials for peatland restoration.

BACKGROUND: Two‐ and three‐dimensional porous activated carbon (C)‐based symmetrical supercapacitors show great potential for extraordinary gravimetric performance as sustainable energy storage. However, the applications of portable and microdimensional supercapacitors are limited by their low volumetric performance stemming from reduced density resulting from increased porosity and high fabrication costs. This study aimed to demonstrate the high gravimetric–volumetric performance of symmetrical supercapacitors from biomass‐based porous carbon‐sources materials through an environmentally benign development method. Unique porous C sourced from TENERA‐type palm oil stick waste was prepared using potassium hydroxide (KOH) as an activating agent. The electrode set resembled a solid plate with an encapsulation density of ≈1.40 g cm−3. RESULT: The study used superior gravimetric–volumetric electrode materials, including an adjusted specific surface area of 934 m2 g−1, single‐doped optimization, and a hollow paper‐stack‐like morphological structure with a high C content of 91%. The results showed that the best electrode in the 1 mol L−1 H2SO4 electrolytes exhibited a high gravimetric capacitance of 233 F g−1 and an extraordinary volumetric capacitance of 326 F cm−3 at 1 A g−1. Furthermore, their coulombic efficiency was ≈99.1% at 10 A g−1. The symmetrical electrode device performed a high gravimetric–volumetric energy density of 19.03 Wh kg−1 and 26.6 Wh L−1 at a maximum output power density of 1.7 kW kg−1 and 1.9 kW L−1, respectively. CONCLUSION: These results indicate that the applied method development and the C‐biomass‐based electrode material design could achieve a high, well‐matched gravimetric–volumetric performance balance in symmetric supercapacitor devices. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Due to their excellent thermophysical properties and high stability, inorganic salts and Forsalt mixtures are considered promising thermal energy storage materials for applications operating at high temperatures. A mixture of binary salts, such as CaCl2 (58 wt.%)-LiCl (42 wt.%), was investigated in this work to understand their thermal properties and stability for use in TES systems. Thermophysical properties, such as onset melting and crystallization temperature, enthalpy of fusion, and crystallization enthalpy, were all investigated experimentally via the use of a simultaneous thermal analyzer. The experimental findings demonstrated a suitable onset melting temperature of 488 °C and a solidification temperature of 480 °C. The heat of fusion was observed as 206 J/g, whereas the heat of crystallization was recorded as 180 J/g. Thermal repeatability tests indicated little variations in melting temperature; however, fusion enthalpies changed significantly over the course of 30 heating-cooling cycles. Additionally, the results obtained from the thermogravimetric analysis showed relatively weak thermal stability with considerable mass changes. This might be caused by the salts decomposing at elevated temperatures. In order to validate this, a high-temperature in-situ X-ray diffraction technique was used to verify the thermal instability of the binary salt mixture with and without thermal cycling. The thermal decomposition of parent salts and the subsequent formation of new phases with the formation of voids were shown to be the cause of thermal instability. It is concluded that the binary mixture of chloride salt showed suitable thermal properties but relatively weak thermal stability, which may limit its use in practical applications. [ABSTRACT FROM AUTHOR]

Microbial fuel cell (MFC) is an emerging energy production technology which converts the chemical energy stored in biologically degradable compounds to electricity at high efficiency. MFC with added mediator can enhance the electron transfer from the microbes to the anode, and used to treat industrial waste gases. In this work, the rate of microbial-reduced mediator reaction at the surface of glassy carbon (GC) electrode in an ethanol-fed MFC was investigated using cyclic voltammetry (CV), and compared with linear sweep voltammetry (LSV). The CV method provided a better estimation of the kinetic parameters than the LSV method due to low concentrations of the mediators used (0.2-1.0 mM), affecting the Tafel behaviours. All of the voltammograms indicated a quasi-reversible process for the anode reaction. The highest exchange current density (io) of 0.14±0.01 mA/cm2 and the highest power output of 0.008 mW/cm2 were obtained using 0.2 mM N′,N′,N′,N′-TMPD as the mediator. The MFC power density of 0.03 mW/cm2 was achieved for 1 mM N-TMPD. Further increase in the power density (0.16 mW/cm2) was possible with carbon cloth electrode. The results of this study confirmed the advantage of a mediator for gaseous pollutant treatment and electricity production in a MFC.