Efficient Solar Evaporation by [Ni(Phen)₃][V₁₄O₃₄Cl]Cl Hybrid Semiconductor Confined in Mesoporous Glass

Abstract

Efficient utilization of solar energy forw ater evaporation is an advanced and environmentally friendly technology to address the crisis of globald rinking water shortages. This study concerns an efficient solar vapor generator comprised of al ightabsorbing and photothermal hybrid compound [Ni(Phen) 3 ] [V 14 O 34 Cl]Cl (NiV 14 )c onfined in mesoporous andh ydrophilic glass (meso-glass). Theg eneratori sf loated in water by supporting it on ad omestic melamine-formaldehyde (MF) foam to ensure evaporation att he water-air interface. The porous structures and poor thermalc onductivities of the meso-glass and MF foam contribute to enabling ac onsistentw ater supply, strong solart hermal localization,a nd less heatd issipation and convection.A ssociated with the strong photothermal role of NiV 14 ,t heses ynergistic effects lead to aw ater evaporation rate of 14.38 kg m À2 h À1 with total water evaporation efficiency of 111.4% under 6suns and ad aily solar water purification yield of 42.00 Lm À2 under 1sun irradiation. This solar evaporation system shows great promise forh igh-efficiency water purification application.Solar energy is considered to be an inexhaustible, free, and green energy source in the world. [1,2] People use solar energy by converting it into chemical energy (photocatalysis and photosynthesis), [3] heat energy (photothermalc onversion), [4] and electricale nergy (photovoltaics). [5] Among such uses, photothermalc onversion has been intensively studied, especially for domestic heating, brine desalination, [6][7][8][9] and power generation. [10] Solar vapor generation provides ap romising approach for seawater desalination to address the issue of globalw ater scarcity. [11] In general, solar evaporation processes include the key steps of solar absorbance and subsequent conversion into heat on absorbers, water supply to illuminated absorbers, and vapor generation,a sw ell as vapor condensation and collection. The four predominant factors that determinet he performance of solar evaporation are the efficiency of solar-thermal conversion of the absorber,h eat management of the system,water supply,a nd the vapor evacuation system.T ypical solar absorber materials, such as graphene oxide (GO), [12] ultrablack absorbers, [13] plasmonic nanoparticles, [14] and thermalconcentrating ceramics, [15] have displayed excellent capability for enhancing the local heat concentrationb ys olar-thermal conversion.A sw ater evaporation is as urface processa tt he very thin water-air interface, minimizing the heat dissipation into the environmenta nd the parasitic heat loss into bulk water is critical for improving solare vaporation performance in terms of heat management. With the assistance of at wo-dimensional water supply path,t he solar evaporation efficiency under 1sun illumination reaches up to 80 %, owing to the minimized heat loss. [11] Integration of surface hydrophobicity and effective photothermal conversion properties onto meshbased membranes has led to significantly improved water evaporation rates, owing to...

Progress in interfacial solar steam generation using low-dimensional and biomass-derived materials

“…Semiconductor material, MoS2 has been reported several times in the field of solar steam generation application in nanosheet form [100][101][102]. Except that a NiV14 based hybrid semiconductor confined in a mesoporous glass has been reported to show water evaporation efficiency of 111.4% under 6 suns [103]. Sometimes to narrow the bandgap, semiconductor materials are doped with plasmonic metal nanoparticles as a plasmonic metal has its own heating effect and can reduce the bandgap of semiconductor materials effectively [96].…”

Efficient Photo‐Thermo‐Electric Conversion Using Polyoxovanadate in Ionic Liquid for Low‐Grade Heat Utilization

“…We have previously reported the hybrid ionic compound of NiV 14 and its application for solar vapor generation owing to its excellent photothermal effect [20] . NiV 14 comprises a [Ni(phen) 3 ] 2+ cation, a spherical cage‐like anion of [V 14 O 34 Cl] − ([V 12 5+ V 2 4+ O 34 Cl] − ) with a Cl − located in the center and another Cl − for charge balance (Figure 1a).…”

Microvessel‐Assisted Environmental Thermal Energy Extraction Enabling 24‐Hour Continuous Interfacial Vapor Generation

“…Concentrations of main cationic ions existed in seawater, i. e., Na + , Mg 2 + , K + and Ca 2 + were significantly reduced to the level far below the drinking water standards established by the World Health Organization, indicating that the collected water is safe for use ( Figure 5b). [37,38] The collected water from wastewater samples were also examined, individually (Figure 5c and d). As presented in Figure 5c, collected water owns an average concentration of 0.01 mg L À 1 of heavy metals (HMs), which is far below the corresponding required concentration for effluent discharge (the stipulated upper Pb 2 + , Cu 2 + , Zn 2 + and Ni 2 + concentrations are 1, 0.5, 2 and 1 mg L À 1 , respectively).…”