The bioanode is the defining feature of microbial fuel cell (MFC) technology and often limits its performance. In the current work, we report the engineering of a novel hierarchically porous architecture as an efficient bioanode, consisting of biocompatible chitosan and vacuum-stripped graphene (CHI/VSG). With the hierarchical pores and unique VSG, an optimized bioanode delivered a remarkable maximum power density of 1530 mW m(-2) in a mediator-less MFC, 78 times higher than a carbon cloth anode.

Covalent bonding of graphene oxide quantum dots (GOQDs) onto amino modified polyvinylidene fluoride (PVDF) membrane has generated a new type of nano-carbon functionalized membrane with significantly enhanced antibacterial and antibiofouling properties. A continuous filtration test using E. coli containing feedwater shows that the relative flux drop over GOQDs modified PVDF is 23%, which is significantly lower than those over pristine PVDF (86%) and GO-sheet modified PVDF (62%) after 10 h of filtration. The presence of GOQD coating layer effectively inactivates E. coli and S. aureus cells, and prevents the biofilm formation on the membrane surface, producing excellent antimicrobial activity and potentially antibiofouling capability, more superior than those of previously reported two-dimensional GO sheets and one-dimensional CNTs modified membranes. The distinctive antimicrobial and antibiofouling performances could be attributed to the unique structure and uniform dispersion of GOQDs, enabling the exposure of a larger fraction of active edges and facilitating the formation of oxidation stress. Furthermore, GOQDs modified membrane possesses satisfying long-term stability and durability due to the strong covalent interaction between PVDF and GOQDs. This study opens up a new synthetic avenue in the fabrication of efficient surface-functionalized polymer membranes for potential waste water treatment and biomolecules separation.

We present a one-step solvothermal approach to prepare uniform graphene-TiO(2) nanocomposites with delicately controlled TiO(2) nanostructures, including ultra-small 2 nm nanoparticles, 12 nm nanoparticles and nanorods. Using three composites as photoanode materials, the effect of nanostructure of graphene-composited TiO(2) on the performance of dye-sensitized solar cells was investigated, and results showed that the ultra-small 2 nm TiO(2)-graphene composite based photoanode exhibited the highest power conversion efficiency of 7.25%.

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conductivity in order to obtain low overpotential as well as to reduce the charge recombination. Fluorine-doped tin oxide (FTO) supported platinum (Pt) is widely used as standard DSSC CE, prepared by sputtering or thermal decomposition processes, owing to its excellent intrinsic properties, such as high catalytic activity, high conductivity, and good chemical stability. [ 3,4 ] However, it is critical to develop low-cost CE substitutes, since Pt is scarce, expensive, and highly demanded in many other industrial applications. Carbon-based materials, [5][6][7] conducting polymers, [8][9][10] transition metal chalcogenides, [11][12][13][14] and other composite materials [ 15,16 ] have demonstrated promising results as effective CEs. Among these materials, transition metal chalcogenides have shown exceptional catalytic activities in catalyzing I 3 − reduction. For instance, CoS electrodeposited on indium tin oxide/ polyethylene naphthalate (ITO/PEN) substrate, giving a higher conversion effi ciency than Pt attributed to its excellent electrocatalytic activity, was introduced as the CE of DSSC for the fi rst time in 2009. [ 11 ] Furthermore, MoS 2 and WS 2 showed comparable power conversion effi ciencies (PCEs) with Pt-FTO due to their pronounced catalytic performance and considerably lower charge transfer resistance. [ 17 ] Ternary chalcogenides offer rich redox reactions arising from the co-existence of two different cations in a single crystal structure, [ 18,19 ] and are promising in the scope of DSSC CE research. However, studies involving ternary transition metal sulfi de materials as DSSC CEs are rarely up-to-date. Some recent works report nanoparticulate CoMoS 4 , NiMoS 4 , and NiCo 2 S 4 deposited fi lms, which have shed new insights into their catalytic activities and demonstrated as effi cient DSSCs CE. [ 20,21 ] However, their synthesis involves multistep screen-printing techniques that are time-consuming and limit the possibility of precise nanoscale control on FTO substrates. Better interfacial properties, such as improved interfacial interaction and electrical contacts between the substrate and prepared material, can be achieved via an in situ preparation method, thus enhancing the performance of catalytic materials. [22][23][24] Chen et al. demonstrated that CoNi 2 S 4 CE-based fl exible DSSCs are prepared from in situ hydrothermal method on carbon fi ber with A one-step in situ tailoring of NiCo 2 S 4 nanostructures is demonstrated on fl uorine-doped tin oxide (FTO) as Pt-free counter electrodes (CEs) for dyesensitized solar cells (DSSCs) with performance surpassing that of a conventional Pt-sputtered CE. An interconnected NiCo 2 S 4 nanosheet network is successfully constructed on the FTO glass via a hydrothermal method, attributed to the synergistic effect of structure-directing hexamethylenetetramine and L-cysteine. A growth mechanism is proposed, and the effects of nanostructures and sulfur atomic percentages on the electrocatalytic performance are discussed in depth. A DSSC with the optimized int...