Wormlike Perovskite Oxide Coupled with Phase‐Change Material for All‐Weather Solar Evaporation and Thermal Storage Applications

Abstract

Interfacial solar‐driven water evaporation has shown promising prospects in desalination technology. However, the lower photothermal conversion efficiency caused by the intermittent nature of sunlight and salt accumulation remains a significant challenge for continuous desalination. Herein, the hierarchical design of interfacial solar evaporation is reported, which realizes enhanced photothermal conversion, waste heat storage/release, and effective thermal management for continuous desalination. The solar evaporator is composed of worm‐like SrCoO3 perovskite oxide anchored on super hydrophilic polyurethane (PU) foam succeeded by in situ polymerization of conducting polypyrrole (SrCoO3@PPy). The energy storage system is introduced within polyurethane matrix by a paraffin block followed by a tongue‐and‐groove structure for convective water transportation, and a heat recovery unit largely reduces heat losses. The solar evaporator possesses excellent evaporation rates (2.13 kg m−2 h−1) along with 93% solar‐to‐vapor conversion efficiency under 1 kw m−2 solar irradiation owing to its minimum equivalent evaporation enthalpy and (0.85 kg m−2 h−1) under intermittent solar irradiation as compared to conventional solar evaporators. More importantly, state‐of‐the‐art experimental investigations validate waste heat recovery/release and the salt‐resistant capability of solar evaporators optimized by computational fluid dynamic simulation. This study breaks conventional solar interfacial evaporation's limitations and demonstrates stable desalination under intermittent sunlight.

Synergy of Light Trapping and Water Management in Interconnected Porous PEDOT:PSS Hydrogels for Efficient Solar-Driven Water Purification

“…As shown in Figure 5f, the detected salt ion concentrations of desalted water after solar desalination with PPH2 were significantly reduced below 1 mg•L −1 , which reached the WHO drinking water standards. 51 In addition, salt accumulation on the surface of the evaporator is one of the most severe problems for continuous water purification from seawater, which causes water transport channels blocking, decreases surface solar absorption, 5 and ultimately decreases evaporation performance. The PPH2 was evaporated in 3.5 wt % NaCl solution under continuous 1 kW•m −2 irradiation to investigate its salt tolerance performance and stability.…”

“…3 Among them, solar-driven water purification has been considered as one of the promising technologies for water purification due to the inexhaustible resources of solar energy. 4,5 To achieve effective solar water purification with higher solar-thermal-vapor conversion efficiency, it is essential to manage water transportation and heat utilization of solar evaporators. 6,7 In this context, many strategies have been proposed to boost solar water purification performance.…”

“…Several water purification technologies, such as filtration, forward/reverse osmosis, distillation, and so on, have been developed for clean water production . Among them, solar-driven water purification has been considered as one of the promising technologies for water purification due to the inexhaustible resources of solar energy. , To achieve effective solar water purification with higher solar-thermal-vapor conversion efficiency, it is essential to manage water transportation and heat utilization of solar evaporators. , In this context, many strategies have been proposed to boost solar water purification performance. One of the most effective strategies was to develop various photothermal materials with efficient solar-to-thermal conversion, such as plasma nanoparticles, , carbon materials, , transition metal nitrides, semiconductors, , and polymers. − Other strategies for reducing heat loss are to confine heat at the air/liquid interface .…”

Advances of 2D‐Enabled Photothermal Materials in Hybrid Solar‐Driven Interfacial Evaporation Systems toward Water‐Fuel‐Energy Crisis

“…However, the traditional evaporation process is mainly the water changing from liquid to vapor as individual molecules, and the intrinsic energy input for the water phase transition limits the evaporation rates. [211,212] Evaporation enthalpy is the energy input to induce the liquid-vapor phase change of water. [25,130,[213][214][215][216] Therefore, the reduced evaporation enthalpy of liquid water can promote vapor generation effectively.…”

Biomass-Printed Hybrid Solar Evaporator Derived from Bio-polluted Invasive Species, a Potential Step toward Carbon Neutrality

“…Hybrid solar evaporators are sought in terms of efficient solar-thermal conversion, effective thermal management via waste heat recovery into useful applications, such as thermoelectricity or water disinfection (hyperthermia effect), salt-collection strategies instead of salt accumulation or clogging in water channels, mechanical robustness, sustainability, and effective utilization of bio-waste as carbon sequestration agents. − For this, several nano-enabled materials have been explored to harvest maximum solar energy and enhance photothermal conversion efficiency, i.e., semiconductive hydrogels, carbon-based materials, in situ conductive polymerization, and plasmonic nanoparticles . However, these evaporation structures lack all desired functions in a single integrated system for the development of an ideal solar absorber. , In this contribution, three-dimensional (3D) geometries, i.e., conical shapes, origami rose, lotus flower, origami 3D, and cylindrical structures, address this dilemma to some extent by enabling multiple reflections of the incident light, and 3D interconnected porous networks, such as polyurethane foam, loofa fiber, and wood sponge, for continuous water transport. − However, these sponge-derived evaporation structures may cause higher thermal conduction to the water body, which lowers the photothermal conversion efficiency due to heat losses .…”