Enhanced salinity gradient energy harvesting with oppositely charged bacterial cellulose-based composite membranes. (October 2022)

• Record Type: Journal Article
• Authors: Sheng, Nan; Zhang, Minghao; Song, Qun; Zhang, Hua; Chen, Shiyan; Wang, Huaping; Zhang, Kai
• Is Part Of: Nano energy. Volume 101(2022)
• Publication Date: 2022-10
• Subjects: Bacterial cellulose -- Composite -- Osmotic energy -- Membrane -- Nanomaterial; Nanoscience -- Periodicals; Nanotechnology -- Periodicals; Nanostructured materials -- Periodicals; Power resources -- Technological innovations -- Periodicals; Nanoscience; Nanostructured materials; Nanotechnology; Power resources -- Technological innovations; Periodicals; 621.042
• DOI: 10.1016/j.nanoen.2022.107548
• Languages: English
• ISSNs: 2211-2855

Abstract

Abstract: Restricted by the inherent properties of the materials, the membranes used for harvesting the salinity gradient energy generally suffer from low ion selectivity, weak permeability or high internal resistance, which heavily limit the output power density. In this work, the integration of one-dimensional bacterial nanofibers and two-dimensional nanosheets is projected to be an effective novel strategy for composite membranes with strongly enhanced output power density by balancing ion selectivity and permeability. Composite membranes as negatively charged bacterial cellulose/graphene oxide and positively charged bacterial cellulose/layered double hydroxide were used as osmotic power generators. For a pair of energy harvesting systems, superposed electrochemical potential difference and ionic flux were created by complementing the diffusion of oppositely charged ions, which achieved an output power density of up to 0.70 W m −2 using artificial sea water and river water. The maximum output power density of single negatively charged membrane reached 4.86 W m −2 . This work demonstrates the practical feasibility and viability of ion-pair laminar membranes as essential platforms for high-performance osmotic power generators by combining nanoconfined coupling surface charge and size effect. Graphical Abstract: ga1 Highlights: This paper first reports a novel osmotic energy harvesting device using bacterial cellulose-based composite membranes. The membranes contain nanofluidic channels and achieve a perfect balance between ion selectivity and ion permeability. This study first uses layered double hydroxide as a suitable platform to study and utilize nanofluidic ion transport.