Green Photothermal Ink for 0D to 3D Solar‐Driven Devices

Abstract

Semiconductors such as TiO 2 can improve the local temperature via nonradiative relaxation induced by intrinsic bandgap absorption. [24] Carbon materials, including graphene, carbon nanotubes, carbonized materials, and so on, can generate heat via the thermal vibration of molecules. [25,26] Compared with plasmonic materials and semiconductors, carbon materials exhibit broad absorption spectra, wide sources, and high light-to-heat conversion efficiency. Therefore, carbon materials are regarded as the most promising candidate for large-scale applications.On the other hand, the performance of a solar-driven device also depends on the material forms and structures. For example, the evaporation performance of a solar-driven evaporator is not only determined by the light-to-heat conversion of the photothermal material, but also affected by the heat and mass transfer processes. Salt accumulation (i.e., scaling) is another critical problem that needs to be considered for practical long-term operation. These problems are related to the surface properties and structure parameters. To name a few examples, an enlarged evaporation area in a certain space could enhance the evaporation, resulting in a lower surface temperature to reduce the heat loss. Zhang et al. fabricated a vertically aligned graphene pillar array with an enlarged evaporation area, providing additional space for vapor escape. [27] Wang et al. prepared a tree-shaped evaporator inspired by Monstera to increase the evaporation area and reduce the surface temperature, which displayed a high evaporation rate of 2.3 kg m −2 h −1 . [28] Wang and co-workers reported an origami-based solar evaporator with a periodic array of mountain-valley folds, enhancing the capture of incident light and recovery of the convective and radiative heat loss. [29] Besides, large pores with low tortuosity can also facilitate the mass transfer process, which is beneficial to reduce heat loss and avoid salt accumulation. Bai and co-workers fabricated a radially, hierarchically structured aerogel, which could reduce heat transfer to bulk water by facilitating water transport from bottom to surface. [30] Zhang et al. designed a self-desalting evaporator system based on a vertically oriented porous foam. [31] The porous structure allows the salt transfer from the surface to the bulk water due to the highly efficient water transport. To address the scaling problem, Zhang et al. developed an aligned Janus MXene-based aerogel, in which the hydrophobic layer could resist the salt crystallization on the surface. [32] Liu et al. achieved continuous production of clean water and avoidance of salt accumulation by hanging photothermal Photothermal materials as well as their forms and structures play a crucial role in the performance and applications of solar-driven devices. There is a growing demand for low-cost, easy-to-shape, and eco-friendly photothermal materials to meet sustainable development. Therefore, a green photothermal ink with excellent photothermal capacity and highly accessible via Ch...

Solar-Driven Evaporators with Thin-Film-Composite Architecture Inspired by Plant Roots for Treating Concentrated Nano-/Submicrometer Emulsions

“…The residual Ca 2+ within the sponge diffuses to the surface and cross-links the alginate network to encapsulate the carbon nanoparticles in Chinese ink (Figure S1). , The appearance of the sponge becomes smooth although the hydrogel layer is transparent (Figures a and S2). As shown in Figure b, the hydrogel layer with a thickness of several tens of micrometers is composited on the sponge surface without significant intrusion, resulting in a typical TFC structure.…”

“…In this work, the carbon nanoparticles in Chinese ink serve as the photothermal agent. Our previous work indicates that both graphite and amorphous carbon nanoparticles are included in Chinese ink, displaying wide absorption of solar irradiation and excellent light-to-heat conversion. , We selected Chinese ink as the photothermal agent because it could be well dispersed in the aqueous solution. As shown in Figure a, the pristine melamine sponge shows a relatively low light absorbance of 29.14% from ultraviolet (UV) to near-infrared (NIR) regions.…”

Effect of reduced graphene oxide hybridization on ZnO nanoparticles sensitivity to NO2 gas: A DFT study

“…The literature of using rGO/ZnO in sensing NO 2 gas is limited to a few articles [12,[35][36][37][38]. All the literature is after 2018.…”

Magnetic‐controllable Janus fibrous membranes with wind‐resistant floatability for airflow‐enhanced solar evaporation

“…In the past decade, many efforts have been devoted to improving the energy conversion efficiency of solar steam evaporators. [8][9][10][11] Up to now, it is generally believed that the evaporation rate is determined by two steps, phase transition of water and subsequent water vapor diffusion. 12,13 To facilitate the phase transition, Janus membranes (JMs) have been considered as the ideal materials due to their unique asymmetric wettability.…”

“…The development of high‐performance evaporators is the core issue in the field of solar steam seawater desalination. In the past decade, many efforts have been devoted to improving the energy conversion efficiency of solar steam evaporators 8–11 . Up to now, it is generally believed that the evaporation rate is determined by two steps, phase transition of water and subsequent water vapor diffusion 12,13 .…”