Green synthesized 3D coconut shell biochar/polyethylene glycol composite as thermal energy storage material

Developing stable, economic, safer and carbon-based nanoparticles from agro solid waste facilitates a new dimension of advancement for eco-friendly nanomaterials in competition to existing nanoparticles. Herewith, a three dimensional highly porous honeycomb structured carbon-based coconut shell (CS) nanoparticle is prepared through green synthesis technique using tube furnace to energies organic phase change material (PCM). CS nanoparticle synthesis using a green approach is incorporated with polyethylene glycol (PEG) using a two-step technique to develop PEG/CS nanocomposite PCM. Thermophysical features of the nanocomposites are characterized using transient hot bridge (ThB), differential scanning calorimeter (DSC) and thermogravimetric analysis (TGA), whereas optical property and chemical stability is evaluated using UV–Vis and FTIR spectrometers. Resulting nanocomposite demonstrates higher thermal conductivity by 114.5 % (improved from 0.24 W/m⋅K to 0.515 W/m⋅K). Energy storage enthalpy increased from 141.2 J/g to 150.1 J/g with 1.0 % weight fraction of CS nanoparticles. Optical absorbance of the nanocomposite is improved by 2.14 times compared to base PCM. The developed nanocomposite samples exhibit extreme thermal stability up to 215 °C. The 3D porous structure of CS nanoparticles shows better contact area with PEG, causing low interfacial thermal resistance for improved thermal network channels and pathways for extra heat transfer and phonon propagation

Optimizing thermal properties and heat transfer in 3D biochar-embedded organic phase change materials for thermal energy storage

Enhancing the thermal properties and light-absorbing capabilities of phase change materials (PCMs) through the utilization of environmentally friendly, economically viable biochar materials is pivotal for optimizing solar energy capture and utilization. Herewith, initially, a green, three-dimensional, eco-friendly carbon nano inclusion is synthesized from Prosopis juliflora through vacuum oven carbonization at 130 °C, followed by size reduction via ball milling, promising high-impact contributions. Subsequently, green-synthesized nano-inclusions are dispersed in PEG-1000, creating advanced nano-enhanced phase change materials with improved thermo-physical properties using a two-step ultrasonication technique for enhanced thermal conductivity. This innovative study comprehensively explores the morphological behaviour, chemical stability, optical absorptivity, thermal properties, and reliability of the PEG-PJ composite. Remarkably, present research revealed that the composite achieved its highest thermal conductivity, an impressive 0.49 W/m⋅K, at 0.7 wt% of 3-D (PJ) biochar. Notably, the melting temperatures of the PEG-PJ composites consistently ranged from 40.1 °C to 40.5 °C. At the same time, their latent heat capacities displayed a notable increase, ranging from 145 J/g to 152.7 J/g, marking a substantial enhancement of 3.968% and 1.758%, respectively. Furthermore, to confirm the reliability and consistency of experimental findings, 500 thermal cycles were performed. Additionally, a numerical analysis study is conducted by utilizing 2-D energy modelling software to simulate the heat transfer rate owing to the improved thermal conductivity of the developed PEG-PJ composite PCM compared to PEG-1000. In conclusion, developed composites optimize solar storage, improve building thermal control, and enhance industrial heat exchangers for sustainable innovation in energy

Nano additive enhanced salt hydrate phase change materials for thermal energy storage

Energy storage plays a vital role in sustainable development. Focus on energy storage using phase change materials (PCMs) are of current research hotspot due to high latent heat value. Nevertheless, poor thermal conductivity, supercooling, phase separation, corrosive nature of salt hydrate is of great concern. Distress related to properties of PCM is resolved using nano additives. Major research focus on the dispersion of nano additive with PCM depends on (a) technique of preparing a novel composite PCM; (b) improvement of their thermophysical characteristic; and (c) advanced application for human comfort without polluting the environment. This article presents a critical review of hybridization techniques of metal, carbon and polymer additives on salt hydrate PCMs. To facilitate researchers, the significant variation on thermophysical properties of salt hydrate with nano additives are vitally compared, analysed and critically reviewed. This review article also includes the advanced application of nano additives-based salt hydrate PCMs

Optical absorptivity and thermal conductivity analysis of silver nanoparticle dispersed salt hydrate PCM

Thermal energy storage using phase change materials (PCM) s are of notable technique towards improving the utilization of solar energy mix within the global energy consumption. Major problem with solar power is its intermittent nature. Phase change materials acts as a thermal battery to store thermal energy received from the sun, and use the same during absence of sun. In spite of numerous advantages PCM suffers due to low thermal conductivity and specifically organic PCMs are flammable in nature. In this particular research investigation, we choose inorganic salt hydrate PCM and disperse silver nanoparticle to enhance their thermal characteristics. Sodium phosphate dibasic dodecahydrate (SPDD) is the opted inorganic salt hydrate PCM. Silver nanoparticle dispersed SPDD PCM are prepared at different composition of SPDD-0.3Ag%, SPDD-0.5Ag% and SPDD-0.7 Ag% using a two-step water bath sonication process. The prepared samples are explored experimentally using FTIR spectroscopy and UV-VIS Spectroscopy to evaluate their chemical and optical absorptivity behavior. Thermal conductivity of the composite inorganic salt hydrate PCM are determined using numerical model available in the literature. Results ensure better optical absorptivity and thermal conductivity for the composite salt hydrate sample with higher concentration of silver nanoparticle. Prepared composite PCM are expected to enhance the thermal energy storage with significance to contribute towards sustainable development goal of clean and affordable energy

Thermal performance and corrosion resistance analysis of inorganic eutectic phase change material with one dimensional carbon nanomaterial

The inherent thermal characteristics, supercooling phenomenon, and corrosion issues associated with salt hydrate phase change materials (PCMs) limit their practical applications. In this research work, we report a newly formulated eutectic salt hydrate PCM using a) sodium sulphate decahydrate (SSD) & b) sodium phosphate dibasic dodecahydrate (SPDD); with a focus on customizing its properties to enhance its suitability for low temperature thermal regulation (achieving a melting point of 27.8 °C and a high heat storage capacity of 215 J/g). Additionally, we have successfully reduced the degree of supercooling and introduced corrosion resistant properties to this PCM. To enhance both the thermal energy transfer rate and optical absorbance of the eutectic PCM, we have incorporated one-dimensional (1D) multiwall carbon nanotube (MWCNT) at various weight fractions, extending up to 0.9 %, utilizing a two-step method. The dispersion and chemical stability of SSD/SPDD + MWCNT nanocomposite are verified through the morphological visual and spectral peaks obtained in Fourier transfer infrared spectroscopy. Additionally, studies evaluating the optical and thermal property reveal a substantial 500 % increase in absorbance, a notable 77.9 % reduction in transmissibility, a thermal conductivity increase from 0.464 W/m⋅K to 0.742 W/m⋅K (reflecting a 59.9 % increment), and the retention of a consistent melting enthalpy of 218.6 J/g. This stability is attributed to the intermolecular interaction with MWCNT. Similary, the degree of supercooling (ΔT s) for the SSD/SPDD EPCM containing MWCNT decreased to 2.2 °C from 16.5 °C, marking an 86 % reduction compared to the pure eutectic salt solution. Furthermore, this composite demonstrated enhanced thermal and chemical stability throughout 200 thermal cycles. Auxiliary ANSYS simulation, with transient boundary condition, are provided to analyze the heat transfer interactions between the thermic fluid and the newly developed PCM when integrated into a thermal regulation system. Subsequently, a corrosion analysis of the developed eutectic PCM and the nanocomposite eutectic PCM exhibits a corrosion rate of 0.018 mpy, well below the permissible level (<5mpy). The insights gained from the development of this nanocomposite PCM offer valuable guidance for the design and creation of tailored eutectic PCM for low-temperature thermal regulation systems, resulting in significant energy savings

Green synthesized 3D coconut shell biochar/polyethylene glycol composite as thermal energy storage material

Developing stable, economic, safer and carbon-based nanoparticles from agro solid waste facilitates a new dimension of advancement for eco-friendly nanomaterials in competition to existing nanoparticles. Herewith, a three dimensional highly porous honeycomb structured carbon-based coconut shell (CS) nanoparticle is prepared through green synthesis technique using tube furnace to energies organic phase change material (PCM). CS nanoparticle synthesis using a green approach is incorporated with polyethylene glycol (PEG) using a two-step technique to develop PEG/CS nanocomposite PCM. Thermophysical features of the nanocomposites are characterized using transient hot bridge (ThB), differential scanning calorimeter (DSC) and thermogravimetric analysis (TGA), whereas optical property and chemical stability is evaluated using UV–Vis and FTIR spectrometers. Resulting nanocomposite demonstrates higher thermal conductivity by 114.5 % (improved from 0.24 W/m⋅K to 0.515 W/m⋅K). Energy storage enthalpy increased from 141.2 J/g to 150.1 J/g with 1.0 % weight fraction of CS nanoparticles. Optical absorbance of the nanocomposite is improved by 2.14 times compared to base PCM. The developed nanocomposite samples exhibit extreme thermal stability up to 215 °C. The 3D porous structure of CS nanoparticles shows better contact area with PEG, causing low interfacial thermal resistance for improved thermal network channels and pathways for extra heat transfer and phonon propagation

Investigation of thermal performance and chemical stability of graphene enhanced phase change material for thermal energy storage

Phase change materials (PCMs) have received widespread thermal energy storage (TES) and release properties due to their unique characteristics. However, the PCMs suffer from poor thermal conductivity, resulting in the least thermal performance and heat transfer characteristics. This research focused on enhancing the heat transfer and storage characteristics by developing an organic paraffin wax composite by dispersing highly conductive graphene powder using a two-step technique. The results show that the developed nano enhanced PCM significantly improves the thermal conductivity by 72.2% at 0.6 wt% of graphene powder. Furthermore, the Fourier transform infrared spectrum shows there is no additional peak observed, means physically and chemically stable, and the reduced light transmission capability was enhanced by 32.0% than pure PCM. Due to its extreme characteristics, the developed PCM is an outstanding material for medium temperature solar thermal energy storage applications

Thermal energy storage behaviour of form-stable polyethylene glycol/MWCNT- based phase change materials

Organic phase change materials (OPCMs) possess a remarkable ability to absorb and release latent heat during phase transitions, making them very promising for storing solar energy. Nevertheless, the extensive use of these materials encounters substantial obstacles arising from intrinsic difficulties, such as limited heat conductivity and chemical stability concerns. The authors of this innovative work have successfully led the way in developing a state-of-the-art nano-enhanced organic phase change material (Ne-OPCM). This novel substance utilizes polyethylene glycol (PEG) as the primary phase transition material, which is smoothly incorporated into a network of polymethyl methacrylate (PMMA) to reduce obstacles caused by molecular size and improve chemical durability. In order to overcome the issue of poor thermal conductivity, the researchers selectively used multi-walled carbon nanotubes (MWCNT) as a conductive filler. This resulted in a significant increase in the thermal conductivity of PEG-1000. In an ongoing study, thermal characteristics of the developed (Ne-OPCM) composites are evaluated for different weight fractions of 0.3 %, 0.7 %, and 1.0 % of MWCNT. In addition to the morphology, thermal property, chemical stability, optical absorptivity and the latent heat of the developed PEG-PMMA/MWCNT (Ne-OPCM) composite are evaluated using FESEM, FT-IR, UV-Vis spectroscopy TGA and DSC instruments. The thermal conductivity of PEG-PMMA/MWCNT (Ne-OPCM) composite was improved by 87.64 % with a dispersion of 0.7 wt% of MWCNT. The DSC conducted highest latent heat and melting point of a PEG-PMMA/MWCNT (NePCM) composite are 139.66 J/g & 40.4 °C occurring at 0.7 wt% of MWCNT. Consequently, the developed (Ne-OPCM) composites have promising potential in practical solar energy storage applications at the temperature range of 35-40 °C

Investigation of thermal performance and chemical stability of graphene enhanced phase change material for thermal energy storage

Phase change materials (PCMs) have received widespread thermal energy storage (TES) and release properties due to their unique characteristics. However, the PCMs suffer from poor thermal conductivity, resulting in the least thermal performance and heat transfer characteristics. This research focused on enhancing the heat transfer and storage characteristics by developing an organic paraffin wax composite by dispersing highly conductive graphene powder using a two-step technique. The results show that the developed nano enhanced PCM significantly improves the thermal conductivity by 72.2 at 0.6Â wt of graphene powder. Furthermore, the Fourier transform infrared spectrum shows there is no additional peak observed, means physically and chemically stable, and the reduced light transmission capability was enhanced by 32.0 than pure PCM. Due to its extreme characteristics, the developed PCM is an outstanding material for medium temperature solar thermal energy storage applications

Nanotechnology Revolutionizing Heat Transfer: A Review of Nanofluid Research and Applications

Nanofluids are a mixture of nanosized particles dispersed in a fluid that has gathered significant interest due to their ability to enhance thermal conduction and heat transfer processes. This comprehensive review delves into formulation methodologies, thermal and physical characteristics, and the applications of nanosuspensions in heat transfer. Various techniques are used to prepare heat transfer nanofluids with uniform dispersion and stable suspension. Common methods include mechanical stirring, sonication, chemical synthesis, and surface modification. These methods are influenced by nanomaterials' dimension, structure, and surface properties, ultimately shaping nanofluids' thermophysical characteristics. Thermophysical properties like thermal conductivity, viscosity, and heat capacity are notably improved in nanofluids compared to base fluids. However, increasing nanoparticle concentration increases the fluid viscosity, requiring careful consideration for practical applications. Heat transfer nanofluids find applications across various industries, including thermal management systems, heat exchangers, electronics cooling, and renewable energy systems. They improve the performance and efficiency of heat transfer equipment, enhance thermal conductivity in electronics cooling, and optimize energy harvesting processes in solar collectors. In conclusion, heat transfer nanofluids present promising opportunities to improve thermal conductivity and heat transfer efficiency in diverse applications. Continued research and development in formulation methods, understanding of thermophysical properties, and exploring new applications are crucial for fully realizing the potential of heat transfer nanofluids in various engineering fields