Porous Metal–Organic Framework CUK-1 for Adsorption Heat Allocation toward Green Applications of Natural Refrigerant Water

Abstract

The development of new water adsorbents that are hydrothermally stable and can operate more efficiently than existing materials is essential for the advancement of water adsorption-driven chillers. Most of the existing benchmark materials and related systems in this field suffer from clear limitations that must be overcome to meet global requirements for sustainable and green energy production and utilization. Here, we report the energy-efficient water sorption properties of three isostructural metal-organic frameworks (MOFs) based on the simple ligand pyridine-2,4-dicarboxylate, named M-CUK-1 [M3(3-OH)2(2,4-pdc)2] (where M = Co 2+ , Ni 2+ or Mg 2+). The highly hydrothermally-stable CUK-1 series feature step-like water adsorption isotherms, relatively high H2O sorption capacities between P/P0 = 0.10-0.25, stable cycling, facile regeneration, and most importantly, benchmark coefficient of performance (COP) values for cooling and heating at low driving temperature. Furthermore, these MOFs are prepared under green hydrothermal conditions in aqueous solutions. Our joint experimental-computational approach revealed that M-CUK-1 integrates several optimal features, resulting in promising materials as advanced water adsorbents for adsorption-driven cooling and heating applications.

Rational design of a robust aluminum metal-organic framework for multi-purpose water-sorption-driven heat allocations

“…Among them, adsorption-based heat transfer (AHT) devices like adsorptiondriven cooling/chiller (AC) and adsorption-driven heat pump (AHP) systems actually emerge as cutting-edge alternatives 4,8 . They target a drastic reduction of energy consumption for cooling and heating owing to the potential use of natural solar or waste heat from industrial plants 4,[9][10][11][12][13][14] . Moreover, water is an environmental-friendly natural refrigerant, non-flammable, abundant, cost-free, and has substantial latent heat of evaporation (40.7 kJ mol −1 ) 11,14 .…”

“…They target a drastic reduction of energy consumption for cooling and heating owing to the potential use of natural solar or waste heat from industrial plants 4,[9][10][11][12][13][14] . Moreover, water is an environmental-friendly natural refrigerant, non-flammable, abundant, cost-free, and has substantial latent heat of evaporation (40.7 kJ mol −1 ) 11,14 . The use of water as working fluid in AHT devices has thus attracted tremendous interest in recent years 4,[9][10][11][14][15][16][17][18][19][20][21][22][23][24] .…”

“…Moreover, water is an environmental-friendly natural refrigerant, non-flammable, abundant, cost-free, and has substantial latent heat of evaporation (40.7 kJ mol −1 ) 11,14 . The use of water as working fluid in AHT devices has thus attracted tremendous interest in recent years 4,[9][10][11][14][15][16][17][18][19][20][21][22][23][24] . AHT system typically operates under a full cycle of water adsorption/desorption ( Supplementary Fig.…”

“…AHT system typically operates under a full cycle of water adsorption/desorption ( Supplementary Fig. 1a) 11,14 . During the adsorption step, heat is taken up from the evaporator (Q ev ), leading to a decrease in temperature enabling AC use, whereas when adsorption is exothermic, heat (Q ads ) is released to cooling water of the adsorbent bed.…”

Systematic Analysis of Materials for Coated Adsorbers for Application in Adsorption Heat Pumps or Refrigeration Systems

“…Activated carbon, zeolite, and silica gel are 2 of 16 mostly used [5,6]. New potential adsorbent materials include silico-alumino-phosphates (SAPO) and alumino-phosphates (ALPO) [7][8][9], in addition to MOFs (metal organic frameworks), such as 101-MIL, which have high net water uptakes [10,11]. Among the new adsorbates, extensive research on salt hydrates has been carried out for possible use in thermal storage processes.…”