Mechanistic insights into the selective photocatalytic degradation of dyes over TiO_(2)/ZSM-11

Photocatalytic degradation is a promising way to eliminate dye contaminants.In this work,a series of TiO2/ZSM-11(TZ)nanocomposites were prepared using a facile solid state dispersion method.Methyl orange(MO),methylene blue(MB),and rhodamine B(RhB)were intentionally chosen as target substrates in the photocatalytic degradation reactions.Compared to pristine TiO2,negative effect was observed on MO degradation while promoted kinetics were collected on MB and RhB over TZ composites.Moreover,a much higher photocatalytic rate was interestingly achieved on RhB than MB,which indicated that a new factor has to be included other than the widely accepted electrostatic interaction mechanism to fully understand the selective photodegradation reactions.Systematic characterizations showed that TiO2 and ZSM-11 physically mixed and maintained both the whole framework and local structure without chemical interaction.The different trends observed in surface area and the photo-absorption ability of TZ composites with reaction performance further excluded both as the promotion mechanism.Instead,adsorption energies predicted by molecular dynamics simulations suggested that differences in the adsorption strength played a critical role.This work provided a deep mechanistic understanding of the selective photocatalytic degradation of dyes reactions,which helps to rationally design highly efficient photocatalysts.

Optimized Bio-inspired Micro-pillar Dry Adhesive and Its Application for an Unmanned Aerial Vehicle Adhering on and Detaching from a Ceiling

Various bio-inspired dry adhesive materials have been investigated.In this work,lithography and silicon deep etching method were used to fabricate bio-inspired micro-pillar dry adhesive materials of which the parameters,such as side length,Height to Side length Aspect Ratio(HSAR),and inter-pillar Distance to Side length Aspect Ratio(DSAR)were comprehensively studied to obtain a dry adhesive with high adhesion.An orthogonal array method was designed and a series of fabrication experiments were conducted to identify optimum parameters,which resulted in a high normal adhesion of 2.98 N·cm^-2 and a shear adhesion of 9.59 N·cm^-2.An adhesion and desorption device was further designed on basis of the optimum dry adhesive,which enables an Unmanned Aerial Vehicle(UAV)to successfully adhere on and detach from a ceiling.This would allow an UAV to stay aloft for prolonged time,which could be invaluable to many applications,such as energy conservation and aerial detection.

The square rod-shaped ionic polymer-metal composite and its application in interventional surgical guide device

Ionic polymer-metal composite(IPMC)is an electro-active polymer material,which has many advantages such as small size,light weight,low driving voltage,large strain,and good biocompatibility.However,the conventional sheet IPMC has the shortcoming of only bending in the two-dimensional plane,which greatly limits the application of IPMC in the field of interventional surgery.In this work,a square rodshaped IPMC with multi-degree-of-freedom motion was fabricated,and the displacement and blocking force of the square rod-shaped IPMC in different directions are measured and analyzed under the DC voltage signal.An interventional catheter was designed using the square rod-shaped IPMC in order to achieve active guidance,and a simulation experiment platform and a model of human aorta were built to successfully complete the in vitro simulation experiment of interventional surgery,which preliminarily verified the feasibility of the square rod-shaped IPMC in the field of interventional surgery.