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Transparent wood for smart glass can decrease indoor energy consumption, while simultaneously offering a comfortable indoor temperature and facilitating effective light harvesting. However, high transparency and ultraviolet (UV)‐blocking ability are mutually exclusive in wood‐based materials due to the presence of lignin. Herein, a Turing pattern‐inspired highly transparent wood (TP‐TW) is fabricated via infiltrating the thermal management materials doped‐epoxy (TMM‐epoxy) into the delignified wood with a Turing pattern. Afterward, the Turing pattern possesses outstanding optical properties (high visible transmittance of ≈76% and low UV transmittance of ≈15%). Moreover, TP‐TW can reduce adverse effects caused by indoor temperature fluctuation and outdoor sunlight, demonstrating high latent heat (25.30 J g−1) and low near‐infrared transmittance. Compared with glass, TP‐TW exhibits a low thermal conductivity of 0.21 W m−1 K−1 and excellent shock‐resistant characteristics. Taken together, these results indicate that TP‐TW is an attractive material for smart glass applications. [ABSTRACT FROM AUTHOR]

Thermal energy storage is important for energy saving and social developing. Low-cost, high thermal conductivity, form-stable composite phase change materials are urgent in energy storage and management. In this work, a novel carbonized wood-based composite phase change materials (TDCW) are fabricated by impregnating of 1-tetradecanol (TD) into carbonized wood (CW). CW as supporting material exhibits porous three-dimensional (3D) structure, high specific surface area and high thermal conductivity. In addition, compared with conventional graphene, carbon nanotubes and other one-dimensional (1D) or two-dimensional (2D) carbon materials, CW is inexpensive and has higher loading content of 73.4 wt%. What's more, CW as supporting material is firstly used in composite phase change materials. According to differential scanning calorimetry measurement and thermogravimetric analysis, TDCW possesses high latent heat, good thermal reliability and favorable thermal stability. In addition, thermal conductivities of PW, CW, TDCW measured at axial direction are all higher than that at radial direction and the thermal conductivity of TDCW is 0.669 Wm −1 K −1  at axial direction at 50 °C, which is 114% higher than that of pure TD. The results of thermal conductivity and surface temperature variation collected by infrared thermal camera under heating and cooling process demonstrate that TDCW is beneficial for thermal management application. This work not only provides a novel and superior supporting material, but also prepares a suitable phase change temperature, high latent heat and high thermal conductivity composite phase change material for thermal energy storage and management civil applications. [ABSTRACT FROM AUTHOR]

Background: With the current rapid economic growth, demands for energy are progressively increasing. Energy shortages have attracted significant attention due to the shrinking availability of non-renewable resources. Therefore, thermal energy storage is one of the solutions that lead to saving of fossil fuels and make systems more cost-effective by the storage of wasted thermal energy. In particular, the application of phase change materials (PCMs) is considered as an effective and efficient approach to thermal energy storage because of the high latent heat storage capacity at small temperature intervals. Nevertheless, leakage problems and low thermal conductivity limit the practical applications of PCMs. Therefore, form-stable phase change materials with high thermal conductivity are urgently needed. Results: A novel form-stable composite phase change material was prepared by incorporating PEG into waste sawdust with 5% EG. In the composites, PEG served as a phase change material, while waste sawdust acted as a carrier matrix. EG was added to help increase the thermal conductivity of the composites. The melting temperature of CPCMs-4 with 5% EG was found to be 58.6 °C with a phase change enthalpy of 145.3 kJ/kg, while the solidifying temperature was 48.5 °C with a phase change enthalpy of 131.4 kJ/kg. The thermal conductivity of CPCMs-4 with 5% EG increased by 23.8% compared with that of CPCMs-4. Moreover, no obvious changes in melting, solidifying temperature, or latent heat after 200 heating-cooling cycles were detected. The supercooling extent of CPCMs-4 with 5% EG decreased by 19.2% compared with PEG. The volume change properties and wettability properties of CPCMs-4 with 5% EG are suitable for thermal energy in terms of practical application. Conclusions: The prepared composites have excellent thermal and form-stable properties and they can be recognized as potential candidates for thermal energy storage as form-stable composite phase change materials. Using simple impregnation techniques with waste sawdust as a supporting material, this study demonstrates an innovative technology for practically and markedly enhancing the adsorption capacity of phase change materials. [ABSTRACT FROM AUTHOR]

Materials for energy collection, conversion and storage are important for overcoming energy-shortage problems. The research reported a nanocomposite containing polyethylene-glycol-10000 (PEG10000) as phase-change-material composite (PCMC) and graphene nanosheets functionalized with Fe 3 O 4 nanoparticles (Fe 3 O 4 -GNS) stored and loaded into a porous carbonized-wood-flour (CWF) matrix. The Fe 3 O 4 -GNS/CWF/PCMC nanocomposite possessed favorable photothermal and magnetocaloric conversion properties. Introducing Fe 3 O 4 -GNS and CWF enhances the inherently low thermal conductivity of the PCMC. Energy was stored by the PCMC and released during the phase transition process. Furthermore, additional magnetothermal conversion and storage via Fe 3 O 4 -GNS component could reversely promote photothermal conversion due to continuous thermal energy supply. PEG10000 as biocompatible and nontoxic PCMC could form efficient combination within Fe 3 O 4 -GNS/CWF/PCMC and conduct least environmental-related effect. The nanocomposite exhibited favorable thermal conversion performance as temperature rising over 65 °C within 150 s, excellent thermal stability below 300 °C, a high melting enthalpy over 95 J/g and crystallization enthalpy over 85 J/g, good stability over 100 heating-cooling cycles, and efficient synergetic energy conversion. The PCMC with Fe 3 O 4 -GNS adsorbed in CWF rapidly converted light and magnetic energy to thermal energy, because of the enhanced thermal conductivity. The Fe 3 O 4 -GNS/CWF/PCMC nanocomposite therefore would have great potential in energy collecting, conversion and storage applications. • Magnetocaloric-assisted photothermal conversion and storage process. • Biomass-derived and environmental materials function as function component. • Thermal conducting enhancement and energy conversion promotion. • High melting enthalpy over 95 J/g, crystallization enthalpy over 85 J/g of samples. • Fast thermal conducting with thermal conductivity up to 0.225 W (m K)−1 of samples. [ABSTRACT FROM AUTHOR]