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The development of phase change materials (PCMs) composites with high light‐to‐thermal energy conversion efficiency is of great importance for solar energy storage. Herein, the preparation of novel PCMs composites by incorporation of fatty amines (FAs) into the carbon membranes (CMs) with aligned nanochannels network is first reported, which is obtained by employing an anodic alumina oxidation membrane as sacrificing template and using polypyrrole and asphalt as carbon precursor via a simple carbonization treatment. The carbonized membranes possess abundant porosity and aligned nanochannels, which is beneficial to harvest solar light combined with their carbon in nature. In addition, organic PCMs, i.e. 1‐Hexadecanamine (HDA, ΔH = 311.1 kJ/kg) and 1‐Aminoheptadecane (AHD, ΔH = 293.0 kJ/kg) can be spontaneously loaded into the nanochannels of CMs by the capillary action and surface tension. The fabricated FAs/CMs composites present an enhanced thermal conductivity ranging from 0.291 to 0.525 W m−1 K−1. Compared to pure FAs, the thermal conductivities of the PCMs composites are 144.8–357.1% higher than that of the control. Meanwhile, the as‐synthesized FAs/CMs composites also exhibit a remarkable high photothermal energy storage efficiency of up to 93.8%, which is one of the highest values reported to date, making them promising candidates for a broad range of applications in solar energy harvesting, conversion, and storage. [ABSTRACT FROM AUTHOR]

The development of high-performance form stable phase change materials (FSPCMs) with higher optical absorbance and phase change enthalpy is of great significance to building energy conservation. A kind of Ti 3 C 2 /pectin aerogels was prepared by self-assembly of pectin and MXene nanosheet (Ti 3 C 2) by solution blending method. These aerogels were directly dipped in the molten dodecylamine (DDA) as the phase change material. The results show that the PCM composites with 3 wt% Ti 3 C 2 have a phase change temperature of 25.47 °C (at which the human body feels comfortable), latent heat of phase change of 218.8 kJ kg−1, and thermal conductivity of 0.1817 W/(m K). The prepared FSPCMs have the characteristics of suitable phase change temperature, high latent heat, good melting/freezing cycle reliability, strong mechanical properties, significant photothermal energy conversion capacity (more than 92%), and good thermal insulation performance. Therefore, the corresponding pectin-based composites with better light absorption and mechanical properties are expected to have broad application prospects in energy conversion and building energy conservation. • Aerogels with enhanced mechanical properties were prepared by self-assembly of Ti3C2 and pectin. • The addition of Mxene effectively improved the solar-thermal conversion efficiency (92.6%) of composites. • The form-stable PCM composite has a phase change enthalpy of 196.3 kJ kg-1 (after 200 cycles). • The dodecylamine used in building energy storage has a suitable phase transition temperature (25.18 °C). [ABSTRACT FROM AUTHOR]

[Display omitted] The development and preparation of multifunctional photothermal conversion materials has far-reaching significance for the utilization of solar energy resources in response to the energy crisis. Herein, we propose a Janus membrane for interfacial solar evaporation and phase change energy storage. The membranes were fabricated via combining the PVA film with multi-shelled hollow spheres (MHS). The membranes have asymmetric wettability, that is, one side is hydrophilic and the other side is hydrophobic. The as-resulted membranes obtain outstanding light absorption without further processing. According to these two advantages, the membranes were applied to solar evaporation. The evaporation rate of the membrane is 1.41 kg*m−2h−1 and the evaporation efficiency is 92.4 % under 1sun irradiation. Moreover, the membrane prepared by impregnating 1-Hexadecanamine (HDA) into MHS possesses excellent tensile strength (2.21 MPa) and photothermal conversion ability. The light-to-thermal conversion efficiency can reach 81.9 % under 1sun irradiation. Therefore, the membranes have broad application prospects in the field of photothermal conversion. [ABSTRACT FROM AUTHOR]

Herein, an approach for development of a novel FS-PCMCs by incorporation of FAs into the GCA, which was derived from one-step hydrothermal of C-MWCNTs and GO followed by annealing treatment, through a simple direct impregnation. The FS-PCMCs was developed for solar energy storage. [Display omitted] The exploitation of excellent performance form-stable phase change material composites (FS-PCMCs) with enhanced photothermal conversion efficiency and high phase change latent heat is of great significance for thermal energy storage. In this work, a new type of FS-PCMCs with superior light-to-thermal conversion performance were created by impregnation of organic phase change material (1-hexadecylamine (HDA) and 1-tetradecylamine (TDA)) into the graphene aerogel (GA) and all-carbon aerogel (GCA) through a simple direct infusion. The multiwalled carbon nanotubes (MWCNTs) are wound around the inner wall of the GA layer to form a three-dimensional (3D) porous network structure to support fatty amine (FAs), thus achieving shape stability before and after phase transition. Moreover, the FS-PCMCs has extremely high phase transition enthalpy (203.1–248 kJ·kg−1) and good recyclability. More importantly, due to the high absorbance of GCA, it can enhance its light absorption capacity and reduce thermal radiation. The light-to-thermal conversion efficiency of the FS-PCMCs is 72.36%-88.25%. Taking the improvement of the comprehensive properties of the FS-PCMCs, the results of this work may open up a way for rational design and preparation of high-performance FS-PCMCs with enhanced storage capacity and light-to-thermal conversion efficiency for the efficient utilization of solar energy. [ABSTRACT FROM AUTHOR]

[Display omitted] The inevitable intermittency of solar illumination during the interfacial evaporation process can cause a reduction in the evaporation performance of solar evaporators. Here, we report the fabrication of a new solar-driven interfacial evaporator using MXene nanosheets as the photothermal layer, modifying them with conjugated microporous polymer hollow microspheres, and then compounding them with the phase change material, in this case, cetyl alcohol, to form a composite evaporator (CE) that can perform all-weather solar interfacial evaporation. By combining interfacial evaporation photothermal conversion with energy storage, the evaporator achieves an evaporation rate of 1.57 kg⋅m−2⋅h−1 at a light intensity of 1 kW⋅m−2 and 2.79 kg⋅m−2⋅h−1 at a light intensity of 2 kW⋅m−2. In addition, the evaporator attains an excellent solar evaporation efficiency of over 91% in both cases and even in salt water. In addition, interestingly, our CE exhibits excellent continuous evaporation ability, e.g., the mass of evaporated water was increased by 0.36 kg⋅m−2 at a light intensity of 2 kW⋅m−2 compared to the cavity evaporator without the phase change material (PCM) when solar light was turned off. These results could be attributed to the fact that the energy released by the incorporated phase change material allows the evaporator to maintain stable evaporation under conditions of insufficient or intermittent solar irradiation, potentially providing a new opportunity for addressing the intermittent problem of evaporation at the solar interface due to unstable light intensity, thus showing great potential for practical continuous desalination. [ABSTRACT FROM AUTHOR]

[Display omitted] Highly efficient harvesting, transfer, and storage of solar energy are of great significance for the sustainability of society Herein, we report the design and synthesis of conjugated microporous polymers hollow spheres (CMPs-HS) coated by graphene (GCMPs-HS) and compounded with the phase change material (PCM) octadecanol (GCMPs@ODA) for efficient solar photothermal conversion. The as-synthesized CMPs-HS shows a high specific surface (519.95 m2 g−1 and 309.26 m2 g−1), good thermostability, and lower thermal conductivity (0.33 W m-2h−1). By coating graphene, the light absorption remained about 90% in the visible light range, which allows light harvest for photothermal conversion. Taking the GCMPs-HS as a functional layer for the solar steam generation (SSG) system, a high evaporation efficiency of near 90% is obtained. After inhaling octadecanol, GCMPs@ODA are prepared and their latent heats are measured to about 217.4 J g−1 and 224.6 J g−1. Under 1 sun irradiation, the photothermal conversion efficiencies of GCMPs@ODA are measured to be 87.15% and 85.83%, the above merits applied in different conditions are superior to photothermal conversion materials reported in the literature. Thus, among the above merits, the fabricated materials are the competitive candidate which shows the great potential in the efficient application of solar energy. [ABSTRACT FROM AUTHOR]

The development of efficient solar photothermal conversion and energy storage composite (SPCSC) is of great significance in solving the imbalance between supply and demand of solar energy utilization in time and space. Herein, we prepare multi-shell hollow spheres by selecting glucose as the template and magnesium carbonate trihydrate (MgCO 3 ·3H 2 O) and chloroplatinic acid hexahydrate (H 2 PtCl 6 ·6H 2 O) as raw materials by hydrothermal-calcination method. Octadecylamine (ODA) is loaded into MSHS by vacuum impregnation to prepare SPCSC with excellent comprehensive properties (MSHS@ODA). The multi-layer hollow microspheres provide the micro-nano space structure for ODA, enhance the heat transfer rate of MSHS@ODA, effectively solve the leakage problem, and enable MSHS@ODA to have a fast photothermal response. MSHS@ODA possesses a high light absorption (75.5%), thermal conductivity (0.35 W·m−1·K−1), and photothermal conversion. The phase change enthalpy can reach 130.7 J·g−1 and maintain a high energy storage density during 100 cyclic phase change tests. Specifically, MSHS@ODA decreases the operating temperature of lithium-ion batteries by 8 °C during discharge, ensuring their stable operation within the optimal temperature range. Based on the above merits, MSHS@ODA may find useful applications in solar thermal storage and effectively managing the thermal conditions of lithium-ion batteries. [Display omitted] • The unique multi-layer hollow cavity structure of MSHS effectively encapsulates PCMs. • The multi-layer structure of MSHS enhances the heat transfer process. • MSHS@ODA has high latent enthalpy, thermal conductivity and good photothermal conversion efficiency. • MSHS@ODA is superhydrophobic and self-cleaning. • MSHS@ODA has better application prospects in battery thermal management. [ABSTRACT FROM AUTHOR]

Developing high-efficiency solar photothermal conversion and storage (SPCS) technology is significant in solving the imbalance between the supply and demand of solar energy utilization in time and space. Aiming at the current research status in the field of SPCS, this review thoroughly examines the phase change materials and substrates in SPCS systems. It elucidates the design principles and methods of SPCS integrated composites. Comparatively, it analyzes the parameters of various types of SPCS composites in terms of photothermal conversion, thermal conductivity, energy density, and cycling stability. Additionally, the review discusses the trade-offs between each parameter to achieve the most optimal effect of SPCS. By sorting out the current status of the application of SPCS technology in solar thermal/photovoltaic, aerospace, buildings, textile, and other industries, this analysis clarifies the requirements for various latent heat, phase change temperature, and other properties under different environmental conditions. Through a comprehensive discussion of SPCS technology, this paper accurately captures the development trend of efficiently and comprehensively utilizing solar energy by analyzing existing scientific problems. It identifies bottlenecks in SPCS technology and suggests future development directions that need focused attention. The insights gained from this analysis may provide a theoretical basis for designing strategies, enhancing performance, and promoting the application of SPCS. [Display omitted] • SPCS technology show high efficiency for energy utilization and management. • SPCS can solve the imbalance in the supply and demand of solar energy utilization. • The study of the design principles and methods of SPCS is important. • SPCS system can solve the energy crisis and environmental pollution. • SPCS systems have great potential for practical water treatment in the future. [ABSTRACT FROM AUTHOR]

The fabrication of composite phase change material (CPCM) with splendid light-to-thermal conversion efficiency and enhanced thermal conductivity is of significance for solar energy storage and transition. Hence, we report the creation of a novel CPCM prepared by impregnating 1-hexadecanamine (HDA) into nickel foam (NF) bearing with carbon nanotubes (CNTs) nanoarray via simple vacuum impregnation for photothermal conversion. The NF bearing with CNTs nanoarray employed in this study show outstanding light absorption of higher than 97% originated from its vertical aligned CNTs nanoarray which makes it possible for trapping the light to the most extent. Moreover, the metal nature of NF coupled with the carbon nature of CNTs nanoarray endow it excellent thermal conductivity, e.g. the thermal conductivity of CPCM is improved by 46.3% compared to that of the pure HDA. Thanks to the high latent heat of HDA (240 J/g), the latent heat of the CPCM are measured to be 132.2 J/g. In addition, it shows excellent thermal stability, e.g. the latent heat of the CPCM remains nearly unchanged after 50 times of melting/freezing cycles. Beneficial from their outstanding light absorption, excellent thermal conductivity and high latent heat, the as-prepared CPCM is an ideal platform solar energy harvesting, storage and transition. Under 1sun irradiation, the light-to-thermal conversion efficiency of the CPCM was measured to be 80.10%. Moreover, we detected the temperature-time curve of the CPCM under 30 V voltage, the result show that the CPCM also has great potential in the electro-to-thermal conversion application. [Display omitted] [ABSTRACT FROM AUTHOR]