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[Display omitted] • Introducing pore on 3D anode enhanced system bio-electrochemical performance. • System start-up time negatively correlated with external surface area of 3D anode. • The abundance of Geobacter inside the pore decreased with the increased pore size. • Increased pore size reduced acidification and improved substrate supply inside the pore. • G-800 3D bio-anode achieved the highest power density of 4593.3 ± 78.2 mW/m3. Microbial electrochemical systems (MESs) are widely studied as a promising technology for recovering bioenergy from wastewater. The anode has a great impact on the performance of the MES and more and more three-dimensional (3D) porous anodes are constructed to improve the bioenergy recovery and the system performance. However, the establishment of suitable pore sizes for MES 3D anodes and the effect of different micron-pore sizes on system performance has not been thoroughly studied. Here, we found the change in pore size affected the start-up time and bio-electrochemical performance by affecting the physical characteristics (surface area and porosity) and mass transfer of the 3D anode. The introduction of pore size on 3D anodes led to the mass transfer limitation of substrate and buffer species, and this phenomenon was severe as pore size decreased. The mass transfer limitation of substrate supply inside the pore imposed a selective pressure to enrich Geobacter from 18.45% to 72.96% when the pore size decreased from 800 μm to 100 μm. However, the acidification brought by the mass transfer limitation of the buffer species affected the activity of microorganisms and played a more important role leading to the 3D anode with 800 μm pore size achieving higher power densities (4593.3 ± 78.2 mW/m3), 1.7 times that of the 3D anode with 100 μm pore size (2782.6 ± 79.2 mW/m3). The present research provides a reference for the construction of high-performance 3D structured anodes and an in-depth understanding of the effect of pore size on system performance. [ABSTRACT FROM AUTHOR]

[Display omitted] • A controlled prelithiated strategy is designed to enhance the ICE of siloxene. • Prelithiated siloxene anodes show high ICE and stable SEI. • The effects of prelithiated condition on physical and electrochemical performance are probed. • Stable 5V full cells is obtained with prelithiated siloxene anodes. Two-dimensional siloxene nanosheet has attracted great attention as an advanced anode for lithium-ion batteries (LIBs) due to its special characters. However, the high surface area leads to a low initial Coulombic efficiency (ICE) and large irreversible capacity, impeding the further application of siloxene. In this work, controlled chemical prelithiation is designed to overcome the issue. The influences of prelithiated conditions on physical and electrochemical performance are researched. Uniform SEI film and high coulombic efficiency is obtained with a 15 min prelithiation process. The prelithiated siloxene anode shows high ICE, superior rate performance and stable cycling performance. When coupled with 5 V-class LiNi 0.5 Mn 1.5 O 4 cathodes, an enhanced capacity retention of 94.3 % is achieved after 200 cycles. This work may be useful for designing advanced anodes for rechargeable batteries. [ABSTRACT FROM AUTHOR]