Synergy of photocatalysis and photothermal effect in integrated 0D perovskite oxide/2D MXene heterostructures for simultaneous water purification and solar steam generation

Inspired by the transpiration and natural photosynthesis of plants, bifunctional properties of mixed-dimensional Ti3C2Tx (MXene)/La0.5Sr0.5CoO3 (LSC) nanohetero-structures to degrade pollutants via photochemical reactions and simultaneously produce fresh water through photothermal effect were explored. Zero-dimensional (0D) LSC in the nanohybrid can absorb short-wave photons to generate active oxidative species for photocatalytic degradation, while photothermal components can convert long-wave photons into heat to evaporate water. More importantly, the hybrid hydrogels are developed by integrating MXene/LSC nanohybrids with polyvinyl alcohol (PVA) and chitosan (CS), which offers excellent thermal insulation, fluent water transport and low water vaporization enthalpy to accelerate water evaporation. Benefiting from the materials selection and design, the assembled MXene/LSC hydrogels (MLH) achieve a light-to-heat conversion efficiency of 92.3 %, and acquire a superior photodegradation efficiency of 97.2 % toward the removal of tetracycline hydrochloride (TC). The MLH evaporator also possesses a significant capacity in the purification of brine and wastewater.

Automated summary

Inspired by plant transpiration and natural photosynthesis, bifunctional properties of mixed-dimensional Ti3C2Tx/MXene and La0.5Sr0.5CoO3/LSC nanohetero-structures were explored for degrading pollutants and producing fresh water simultaneously. Through the assembly of MXene/LSC hydrogels, high light-to-heat conversion efficiency and photodegradation efficiency were achieved, along with excellent water evaporation capacity for purifying brine and wastewater.