Studies On Preparation And Adsorption Of Free-standing MoO₃/Carbon Cloth Composites

In recent years,rapid industrial expansion has led to a sharp increase in the wastewater discharge.In particular,organic pollution has become an alarming environmental issue due to its high toxicity and strong damage.Compared to other water purification technologies,adsorption strategy has the advantages of low cost,fast removal speed,no condition required and good adaption,which can serve as a promising and efficient scavenger for pollutants.However,multiple tedious preparation,difficult separation process and narrow pH work range of adsorbents seriously limited their actual use.Herein,novel free-standing MoO₃/carbon cloth was developed via one-step hydrothermal method,and its adsorption toward organic pollutants was studied.To tackle the complicated separation of powdery adsorbents,free-standing h-MoO₃@carbon cloth core-shell structure through hydrothermal process was fabricated,where the carbon fiber in the core was covered with h-MoO₃ micro-rods as shell.The obtained sample possessed high adsorption efficiency and uptake for several dyes（RhB,MB and CV）.Nearly 92%RhB,100%MB and 100%CV were adsorbed while flowing through the h-MoO₃@carbon cloth-based filtration device.The adsorption capacity of h-MoO₃@carbon cloth for RhB and CV reached up to 5335 and 3665 mg/m²,respectively.Moreover,h-MoO₃@carbon cloth core-shell structure was free-standing and flexible,which realized the adsorptive filtration and its facile separation after adsorption.Further,highly free-standing and flexibleα-MoO₃ flowers/carbon cloth was obtained.The flowers consisted of denseα-MoO₃ microfibers in radial orientation.More and bigger flowers with radiatedα-MoO₃ microfibers not only guaranteed high specific surface area and abundant micro-channels,but also remarkably shortened the pollutant diffusion path and further lowered its transporting resistance,thus contributing to good adsorption for dyes（100%RhB,100%MB,100%CV and 73%MO）and drugs（55.4%noroxin and 49.4%tetracycline hydrochloride）after one-cycle adsorption.The adsorption capacity ofα-MoO₃flowers for RhB,MB,and CV achieved 4974,6217,and 3886 mg/m²,respectively.Additionally,this novel adsorbent can adapt to a wide pH range,maintaining the excellent capacity of 4774 and 4473 mg/m² toward RhB at pH of 2.0 and 12.0.α-MoO₃ flowers on a carbon cloth realized the adsorptive filtration for organics removal and simple separation,which required no conditions and no energy consumption during adsorption as compared to the powdery adsorbents.