Controllable fabrication of tendril-inspired hierarchical hybrid membrane for efficient recovering tellurium from photovoltaic waste

Fabrication of membrane-based adsorbent with outstanding functions for efficient recovering tellurium from photovoltaic waste has been intriguing but is still challenging. Inspired by the winding of tendrils, herein, a membrane-based adsorbent for tellurium separation has been fabricated via winding calcined micron-sized Mg-Al layer double hydroxides (LDHs) fibers with the acid of ultralong MnO2 nanowires (UL-MnO2-NWs). To obtain the calcined LDHs fibers, Al2O2 fibers was fabricated by template-directed synthesis employing cotton fibers as templates, and then the calcined LDHs fibers were prepared via crystal growth on Al2O3 fibers surface and subsequent calcination treatment. UL-MnO2-NWs were obtained by a hydrophobic route. The immobilized LDHs in the tendril-inspired membrane allow the tellurium to be adsorbed in matrix from the simulate leaching solution of CdTe photovoltaic waste with permeate flux of 34 m(3)/m(2)h. It is worth mentioning that the tendril-inspired membrane achieves ultrahigh removal efficiency up to 98.73%. The static soaking tests proved the excellent mechanical stability of the tendril-inspired membrane. More importantly, the tendril-inspired membrane can be regenerated via elution and calcination processes, which match well with the requirements for practical separation applications. Under the cyclic tests, the tendril-inspired membrane still maintains a high level of separation after 5 cycles. As a high-efficient, mechanically stable, and regenerated membrane-based adsorbent, tendrils-inspired membrane has tremendous potential to handle and recycle toxic tellurium containing compounds. (C) 2019 Elsevier Ltd. All rights reserved.