Sugarcane‐Based Photothermal Materials for Efficient Solar Steam Generation

Abstract

Solar steam generation is a promising strategy for harvesting solar energy for diverse applications such as desalination and wastewater treatment. Here, we demonstrate the fabrication of polypyrrole modified sugarcane (PPy‐SC) as efficient photothermal material for solar steam generation. The PPy‐SC possesses various close‐packed open channels in horizontal plane and super hydrophilic wettability which is beneficial for rapid transportation of water molecules. In combination with its abundant porosity (47%), low apparent density (80 mg cm−3), low thermal conductivity (0.042 W m−1 K−1), and broad light absorption (90%). The prepared PPy‐SC exhibits a high evaporation rate of 1.59 kg m−2 h−1 and conversion efficiency of 90.6%, under 1 sun irradiation. In addition, the PPy‐SC also shows good performance in desalination. With the merits of low‐cost, eco‐friendly, simple fabrication process, high solar energy conversion efficiency, the PPy‐SC shows great potential as an efficient photothermal material for solar steam generation.

Intensifying Solar Interfacial Heat Accumulation for Clean Water Generation Excluding Heavy Metal Ions and Oil Emulsions

“…Polypyrrole (PPy) is one of the most stable conductive polymers due to its heterocyclic structure, which exhibits diffuse reflection and efficient solar absorption that promotes its direct application in solar-driven devices. [23][24][25][26] Indeed, nickel foam substrate was selected to support the stability of PPy NPs due to its open porous structure and exploit the intrinsic defuse reflection of conductive PPy NPs, [27] high porosity, and intrinsic strength with better uniformity. For this, monomer solutions (A&B) were prepared, as described in the Experimental Section (2.2), and sprayed successively for IPNF.…”

“…[32][33][34] However, water transportation is also significantly improved due to the excellent superhydrophilic combination of in situ-polymerized nickel foam and PU substrate, whereas the rough surface texture boosts the wetting capacity. [26,35] Indeed, the micropores of both surfaces are naturally crosslinked and interconnected vertically to manifest the superhydrophilicity of the water channel for wicking up water and vapor escaping, as shown in Video S2, Supporting Information. Figure S4, Supporting Information, shows the contact angle test of the IPNF solar evaporator, where the water droplet interacts with the IPNF surface and is abruptly absorbed (0.001 s).…”

Highly Efficient Solar Steam Generation under Low Solar Flux via Carbon‐Nanotube‐Modified Sugarcane

“…The solar energy conversion efficiency of CNT-SC under 1 sun is 94.2%, which is higher than most recently reported biomass-based solar evaporators and is the highest efficiency among the sugarcane-based materials (Figure 4c and Table S1). [22,25,31,32,35,[42][43][44][45][46] With the increase of solar illumination up to 5 sun, visible steam can be observed on the CNT-SC surface with the efficiency of 95.8%, demonstrating the fast evaporation of water.…”

“…With these in mind, absorbers using biomass such as wood, [21,30] mushroom, [22] sugarcane, [31,32] bamboo, [33,34] and daikon [35] have been considered due to their abundance, low cost, renewability, and biodegradability. Different from the traditional biomass carbon materials, which are created by pyrolysis, the recently reported biomass-based materials are used directly as the templet/structural portion in their original state without macroscopic damage of structure.…”

“…[32] Li's group demonstrated a fabrication of polypyrrole-modified sugarcane as an efficient solar thermal material for solar steam generation with an efficiency of 90.6% under 1 sun. [31] The light absorption/solar steam generation performance is enhanced by surface modification. Although much of the previous research has improved the efficiency of sugarcane to a certain extent, it is necessary to find a more efficient absorption layer to enhance the efficiency, especially under low solar flux (<1 sun) conforming to real conditions.…”