Facile fabrication of reusable starch sponge with adjustable crosslinked networks for efficient nest-trap and in situ photodegrade methylene blue

Bingbing Gao; Congyun Zhang; Ran Dong; Yukun Chen; Shuidong Zhang

doi:10.1016/j.carbpol.2023.121342

Facile fabrication of reusable starch sponge with adjustable crosslinked networks for efficient nest-trap and in situ photodegrade methylene blue

Carbohydr Polym. 2023 Dec 15:322:121342. doi: 10.1016/j.carbpol.2023.121342. Epub 2023 Aug 29.

Authors

Bingbing Gao¹, Congyun Zhang², Ran Dong¹, Yukun Chen¹, Shuidong Zhang³

Affiliations

¹ School of Mechanical and Automotive Engineering, South China University of Technology, No. 381 Wushan Road, Tianhe District, Guangzhou 510640, China.
² School of Environmental Science and Engineering, State Key Laboratory of Bio-fibers and Eco-textiles, Shandong Collaborative Innovation Center of Marine Biobased Fibers and Ecological Textiles, Qingdao University, Qingdao 266071, China.
³ School of Mechanical and Automotive Engineering, South China University of Technology, No. 381 Wushan Road, Tianhe District, Guangzhou 510640, China; Guangdong Key Laboratory of Technique and Equipment for Macromolecular Advanced Manufacturing, South China University of Technology, Guangzhou 510640, China; State Key Laboratory of Pulp and Paper Engineering, South China University of Technology, Guangzhou 510640, China. Electronic address: starch@scut.edu.cn.

PMID: 37839847
DOI: 10.1016/j.carbpol.2023.121342

Abstract

The fabrication of reusable natural polysaccharide sponges with nanoscale dispersed photocatalysts to achieve robust photocatalytic efficiency is desirable yet challenging. Herein, inspired by the nesting behavior when fishing, we designed reusable starch sponge with chemically anchored nano-ZnO into carboxylated starch matrix by thermoplastic interfacial reactions and solvent replacement for absorbing and photodegrading methylene blue (MB) in situ. The plasticization and interfacial reactions promoted a simultaneous increase in the reactivity of the starch hydroxyl/carboxyl groups and the specific surface area of ZnO. Meanwhile, the crosslinked networks of starch sponge could be adjusted by varying the ZnO and carboxylic groups contents. The results of photodegradation experiments revealed the recyclable closed-loop process of attraction-trapping-photodegradation of MB was successfully realized, achieving the effect of killing three birds with one stone. The reusable starch sponge with homogeneous dispersion of nano-ZnO by constructing three-dimensional porous channels possessed the high enrichment capacity and the remarkable photocatalysis efficiency with 150 mg/L ZnO. Under UV irradiation, the starch sponge degraded 97 % of MB with 1.67 × 10^-3 min^-1 photodegradation rate constant even after five cycles, which exceeded most existing photocatalytic systems. Overall, the reusable starch sponge with adjustable structure provided new insights for multifunctional bio-based photocatalyst loading systems.

Keywords: Adjustable crosslinked networks; Attraction-trapping-photodegradation; Interfacial thermal-reactions; Recyclable closed-loop process; Reusable starch sponge.