Modified PET fiber sponge with synergistic photothermal conversion function for efficient solar interfacial evaporation

Insight into the role of the channel in photothermal materials for solar interfacial water evaporation

A loofah-based all-day-round solar evaporator with phenolic lignin as the light-absorbing material for a highly efficient photothermal conversion

Excellent acid resistance and MXene enhanced photothermal conversion of bilayered porous solar evaporator fabricated by palygorskite and pectin

The application of photothermal materials for achieving continuous and efficient solar interfacial evaporation possesses substantial research significance in solar desalination. To realize continuous and efficient evaporation, interfacial evaporation materials must integrate high light absorption capacity, superior photothermal conversion performance, sufficient water supply, and buoyancy. In this study, polyvinylidene fluoride/carbon nanotubes (PVDF/CNT) self-floating porous microspheres, suitable for solar interfacial water evaporation, were synthesized via a convenient phase transformation method. The microspheres’ distinct composition and porous structure enable effective sunlight absorption, sufficient water flow, and quick steam discharge. Additionally, the performance of the microspheres is enhanced as the content of CNTs increases. These microspheres can absorb up to 93.8% of incident sunlight and elevate the water surface temperature to 41.5 °C within 2 minutes. Under one-sun illumination, the water evaporation rate (WER) reaches 1.485 kg/m2·h, with a solar energy conversion efficiency (SECE) of 93.1%.

Pyramid-shaped solar evaporator with high-efficient interfacial evaporation and salt harvesting capability

A 3D Corncob-based interfacial solar evaporator enhanced by environment energy with salt-rejecting and anti-corrosion for seawater distillation

Synergistic effect of superhydrophilic skeleton decorated with hierarchical micro/nanostructures and graphene oxide on solar evaporation

Solar-driven water evaporation is essential to provide sustainable and ecofriendly sources of fresh water. However, there are still great challenges in preparing materials with broadband light absorption for high photothermal efficiency as well as in designing devices with large evaporation areas and small heat dissipation areas to boost the water evaporation rate. We designed a hanging-mode solar evaporator based on the polyaniline/carbon nanotube (PANI/CNT) fabric, in which the photothermal fabric acts as the solar evaporator and the micropores on the cotton fabric act as the water transfer channels. The hanging mode provides efficient evaporation at both interfaces by greatly reducing the heat dissipation area. The hanging mode PANI/CNT fabric solar evaporator can achieve an evaporation rate of 2.81 kg·m-2·h-1 and a photothermal efficiency of 91.74% under a solar illumination of 1 kW·m-2. This high-performance evaporator is designed by regulating the photothermal material and evaporation device, which provides a novel strategy for sustainable desalination.

Bamboo shoot-based evaporator with self-cleaning and mildew-resistant for efficient solar steam generation

Interfacial solar evaporation based on Janus films: An effective strategy to improve salt tolerance and antifouling performance

As a sustainable and clean water production technology, solar thermal water evaporation has been extensively studied in the past few years. One challenge is that upon operation, salt would form on surface of the solar absorbers leading to inefficient water supply and light absorption and thus much reduced water vaporization rate. To address this problem, a simple solar evaporator based on an array of aligned millineedles for efficient solar water evaporation and controlled site-specific salt formation is demonstrated. The maximum solar evaporation rate achieved is 2.94kg m-2 h-1 under one Sun irradiation in brine of high salinity (25wt% NaCl), achieving energy conversion efficiency of 94.5% simultaneously. More importantly, the spontaneously site-specific salt formation on the tips of millineedles endows this solar evaporator with salt harvesting capacity. Rationally separating the clean water and salt from brine by condensation and gravity assistance, this tip-preferential crystallization solar evaporator is not affected by the salt clogging compared with conventional 2D solar evaporators. This study provides new insights on the design of solar evaporators and advances their applications in sustainable seawater desalination and wastewater management.

A thermos-inspired double structural design for efficient and sustainable solar-driven water purification

The emerging solar interfacial evaporation (SIE) technology is an effective measure to address freshwater resources. An efficient and stable solar interfacial evaporator cannot be achieved without the synergy of three key factors: water transport, solar thermal conversion, and thermal management. The performance of a solar interfacial evaporator can be improved through the rational selection of materials and the structural design of these three key factors. Due to superior nanostructures, electrospun nanofibrous materials often exhibit some unique properties that facilitate the construction of solar interface evaporators with good performance. So far, electrospinning has been used to prepare structures such as solar absorbers, water transportation, and thermal insulation in various solar interfacial evaporators. This review presents the fundamental research and technological development in the application of electrospinning techniques to solar interfacial evaporators on structures, morphology, and properties. Then, the latest advances in the use of electrospinning technology in solar interfacial evaporators are summarized and the current issues facing the application of electrospinning technology to solar interfacial evaporators are presented. These systematic discussions can provide ideas and approaches for the rational design of electrospun nanofiber materials for solar interfacial evaporators in the future.

Efficient interfacial solar evaporation using a novel carbonized foam as photo-thermal converter

Solar interfacial evaporation is an innovative and environmentally friendly technology for producing freshwater from seawater. However, current interfacial evaporators are costly to manufacture, have poor tolerance to environmental conditions, exhibit instability in evaporation efficiency in highly saline solutions, and fail to prevent salt crystallization. The production of user-friendly, durable and salt-resistant interfacial evaporators remains a significant challenge. By spraying graphene oxide on a nonwoven material using PVA as a binder and adding biphasic Cu x S by an in situ growth method, we designed 2D/3D micro- and nanostructured graphene oxide nanosheets/copper sulfide nanowires (GO/Cu x S) with synergistic photo-thermal effects in the full spectral range. The evaporation efficiency in pure water was 94.61% with an evaporation rate of 1.5622 kg m-2 h-1. In addition, we enhanced convection by employing a vertically aligned water-guide rod structure design, where the concentration difference drives salt dissolution thereby reducing the formation of salt crystals. The evaporation efficiency in 20% salt water was 80.41% with an evaporation rate of 1.3228 kg m-2 h-1 and long-term stability of brine evaporation was demonstrated under continuous sunlight. This solar steam generator expands the potential application areas of desalination and wastewater purification.