Search

With the increasing global instability in the development of the world, the efficient storage and conversion of energy have alerted attention. In this work, a novel conjugated microporous polymer hollow spheres (CMPHS) with a high specific surface (323 m2 g−1) and unique cavity structure are creatively prepared. By treatment with simple carbonization, the resulting carbonized microspheres (CCMPHS) show a high light absorption (80%) and outstanding thermal stability (thermal decomposition at 506 °C). On basis of the abundant micropores distributed on the surface of microspheres, the organic phase change materials (PCMs) i.e., fatty alcohols (tetradecanol (TD), hexadecanol (HD), and octadecanol (OD)), are successfully embedded into CCMPHS to afford a kind of new composite (CCMPHS@PCMs) for energy storage and conversion. The three kinds of CCMPHS@PCMs exhibit high latent heats (220.1 kJ kg−1, 244.6 kJ kg−1, and 228.8 kJ kg−1, respectively.). In terms of energy conversion, the photothermal conversion efficiencies of CCMPHS@PCMs are up to 86.83%, 89.45%, and 85.40% and the electrothermal conversion efficiencies are 83.81%, 81.10%, and 90.50%, which possess one of the highest values among the most of similar composites embed with PCMs reported to dates. Based on the advantages of simple fabrication, easy to scale up, high energy density, and conversion efficiency, the CCMPHS@PCMs are expected to be one of the most promising candidates as efficient PCMs composite for a variety of practical applications such as solar or electric energy harvesting, storage, conversion, and so on. • Hollow porous polymers spheres prepared by template method. • The CMPHS and CCMPHS exhibits unique nano spherical morphology, abundant porosity. • The CCMPHS shows excellent solar light absorption about 80% at the range of visible light and superior thermal stability which make decomposition at 506 °C. • The CCMPHS@PCMs possesses huge energy density, and storage/conversion potential which possess 90% photothermal conversion and thermoelectric conversion efficiency. • The CCMPHS@PCMs has great advantages for their simple and scalable manufacture process. [ABSTRACT FROM AUTHOR]

Phase change materials (PCMs) composites are of great importance for a wide range of applications in energy conversion and storage, waste heat recovery and utilization, thermal energy management in building, electronic devices cooling and heat insulation, etc. Herein, a novel strategy for the fabrication of PCM composites for solar/electro energy conversion and storage is reported. The polypyrrole (PPy) coated conjugated microporous polymers/expanded graphene (EG) carbon aerogels/HDA (PCMPECAs/HDA) composites were firstly obtained via Sonogashira–Hagihara cross-coupling reaction followed by a carbonization treatment, PPy coating and finally 1-Hexadecylamine (HDA) impregnation. The introduction of EG and PPy was to improve the porosity, thermal conductivity and photothermal performance. The resultant PCMPECAs/HDA composites exhibited excellent comprehensive performances, including relatively high thermal conductivity of up to 234.0% that of HDA, high energy storage density up to 205.10 kJ/kg, excellent shape and thermal stability and a remarkable photothermal conversion and storage efficiency of up to 93.5%, respectively. And after 300 times thermal and cooling cycles, the latent heat of PCMPECAs/HDA still remains up to 150.20 kJ/kg. Besides, the resultant composites also manifest excellent electro-thermal effect at low voltage. Due to the aforementioned advantages, PCMPECAs/HDA composites possess great potential applications in solar/electric energy conversion and storage. • Conjugated microporous polymer carbon aerogels composites are first reported. • The latent heat of PCMPECAs/HDA composites were tested up to 205.10 kJ/kg • The resultant composites show an ultrahigh photothermal conversion efficiency (93.5%). • The shape-stable composite has a phase change enthalpy of 150.20 kJ kg-1 after 300 cycles. • The resultant composites presented an excellent electro-thermal effect at low voltage. [ABSTRACT FROM AUTHOR]

Solar-driven interface evaporation has received much attention due to its high-efficiency photothermal conversion efficiency. However, in practical application, it is difficult to monitor whether the evaporation efficiency of photothermal conversion materials can maintain high efficiency and stability for a long time. In this paper, taking surface modified coconut fiber (SCF) as photothermal material, we designed a set of evaporation efficiency monitoring device (EEMD) and demonstrated the strategy of building a solar evaporation efficiency monitoring system. The SCF shows superhydrophilic wettability, and its vertical multi-stage open-framework structure is benefit to the rapid transport of water. Under 1 kW m−2 illumination, evaporation rate of SCF is 1.5 kg m−2 h−1, evaporation efficiency is 90.2%. In 20% NaCl, evaporation rate of SCF is 1.37 kg m−2 h−1, and energy conversion efficiency is 85.3%. In order to monitor the stability of evaporator efficiency, we designed a simple EEMD which applied platinum wire electrode to monitor the change of electric potential in the evaporator. The results show that the electric potential is positively correlated with the evaporation efficiency. EEMD provides a new monitoring method for the efficient and stable operation of solar evaporator. We demonstrate for the first time a new strategy for monitoring the evaporation efficiency of photothermal materials of solar steam generators by evaporation efficiency monitoring device (EEMD). The findings obtained from this study may provide a simple and versatile way for the efficient and stable operation of solar evaporator. Image 1 • Evaporation Efficiency Monitoring Device (EEMD) was designed for solar steam generation. • EEMD provides a new monitoring method for the efficient and stable operation of solar evaporator. • The electric potential is positively correlated with the evaporation efficiency. [ABSTRACT FROM AUTHOR]