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A cellulose‐based photocatalytic membrane was fabricated by in situ growth of the NH2‐MIL‐125 nanoparticles onto the surfaces of the ultrathin titania (TiO2) gel layers pre‐coated cellulose nanofibres of natural cellulose substance (commercial laboratory filter paper). The NH2‐MIL‐125 nanoparticles were grown on the surface of the titania gel coated cellulose nanofibres via a one‐step solvothermal method. The resultant composite membranes maintained the initial hierarchical network structures of the bulk cellulose substance, consisting titania gel layer coated cellulose nanofibres with NH2‐MIL‐125 nanoparticles anchored on the surfaces. Owing to the hierarchical porous structure of the cellulose substrates as well as the effective heterostructure formation between the NH2‐MIL‐125 particles and the TiO2 layers, the composites showed enhanced photocatalytic performances. The NH2‐MIL‐125/TiO2/cellulose composite composed of 15.82 wt% NH2‐MIL‐125 content with nanoparticles sizes of 100–200 nm showed an apparent rate constant of 0.032 min−1 in photocatalytic degradation of Rhodamine B (RhB), which was higher than those of the NH2‐MIL‐125/cellulose composite and the TiO2/cellulose composite. It was demonstrated that pre‐coating of the cellulose nanofibres with ultrathin titania gel layers was essential for the growth of the NH2‐MIL‐125 nanoparticles thereon. [ABSTRACT FROM AUTHOR]

A novel cellulose substance (ordinary laboratory filter paper) derived hierarchical carbon/tin-oxide/molybdenum-dioxide (carbon@SnO2@MoO2) ternary nanoarchitectonic was fabricated by the self-assembly process and subsequent carbonization treatment. The resultant nanocomposite was composed of thin tin oxide layer sandwiched between the porous carbon nanofibers and the external molybdenum dioxide coating layer, where the thickness of the molybdenum dioxide coating layer was controlled facilely. As being utilized as an anodic material for lithium-ion batteries, the nanocomposite displayed high reversible capacity and good rate performance that are superior to those of the carbon@MoO2 hybrid without SnO2. The good electrochemical performance of the anode was benefited from the sophisticated multi-level structures of the composite, small sizes of the tin oxide (ca. 5 nm) and molybdenum dioxide (ca. 6 nm) nanocrystallites contained therein, and the synergistic interactions between the tin oxide layer, the outer molybdenum dioxide coating layers, as well as the porous carbon buffering matrix. For such a composite with MoO2 and SnO2 contents of 20 and 10%, respectively, by weight, it delivered a specific capacity of 608.1 mAh g−1 after 100 discharge/charge cycles at the current rate of 100 mA g−1. The current work presents a facile and cost-effective pathway to synthesize bio-substance derived nanocomposite materials for energy applications. [ABSTRACT FROM AUTHOR]

A hierarchical CoS–nanoparticle/carbon nanofibrous composite composed of CoS nanoparticles conformably anchored on the carbon fibres was fabricated by using a natural cellulose substance (e.g., ordinary laboratory filter paper) as the scaffold as well as the carbon source, and was applied as a high-performance anodic material for lithium-ion batteries. The initial cellulose substance (filter paper) was first carbonized at 450 °C, and then treated by KOH at 800 °C to acquire the activated carbon fibres; thereafter, the CoS nanoparticles were deposited onto the activated carbon fibres through a hydrothermal process. Such a porous three-dimensional network structure of the resultant CoS/carbon nanofibrous material inherited from the original cellulose substance resulted in high lithium ion diffusion coefficient, fast electronic transport and fine pseudo-capacitive effect. The composite with 37.0 wt% of cobalt sulfide displayed a high initial specific capacity of 1137.3 mA h g−1 and a stable reversible capacity of 576.7 mA h g−1 after 200 cycles at a current density of 100 mA g−1. Owing to the high specific surface area and porous structure of the CoS–nanoparticle/carbon nanofibrous composite, it delivered superior electrochemical performance during the lithiation/delithiation progress when used as an anodic material for lithium-ion batteries. [ABSTRACT FROM AUTHOR]

Introducing the sophisticated morphologies and structures of natural substances into artificial materials provides a promising strategy for the fabrication of functional materials with tailored structures and functionalities. Herein, our recent advances achieved in the fabrication of hierarchically structured functional materials derived from natural cellulose substances (e.g., ordinary laboratory filter paper) for lithium-ion batteries are reviewed. The surface sol–gel process was employed to fabricate metal oxides (Sn, Ti, Fe, etc.), silica and silicon based nanocomposites by using the corresponding metal alkoxides as the precursors, which faithfully inherited the unique porous network structures of the initial cellulose substances. However, the nanomaterials synthesized as such are limited to the above-mentioned species due to the limitation of specific metal alkoxide precursors used. To break this limitation, specific polyoxometalate clusters were employed as the building blocks to be assembled onto the surfaces of cellulose nanofibres and eventually to obtain the corresponding molybdenum based nanomaterials with three-dimensional porous network structures and specific properties. These cellulose derived nanocomposites exhibit improved lithium storage capacities and cycling stabilities when applied as anodic materials for lithium-ion batteries, resulting from the unique hierarchically porous network structures inherited from the initial cellulose substance and the strong synergistic interactions among the components contained therein. [ABSTRACT FROM AUTHOR]

A bio-inspired nanofibrous MnO2-TiO2-carbon composite was prepared by utilizing natural cellulosic substances (e.g., ordinary quantitative ashless filter paper) as both the carbon source and structural matrix. Mesoporous MnO2 nanosheets were densely immobilized on an ultrathin titania film precoated with cellulose-derived carbon nanofibers, which gave a hierarchical MnO2-TiO2-carbon nanoarchitecture and exhibited excellent electrochemical performances when used as an anodic material for lithium-ion batteries. The MnO2-TiO2-carbon composite with a MnO2 content of 47.28 wt % exhibited a specific discharge capacity of 677 mAh g−1 after 130 repeated charge/discharge cycles at a current rate of 100 mA g−1. The contribution percentage of MnO2 in the composite material is equivalent to 95.1% of the theoretical capacity of MnO2 (1230 mAh g−1). The ultrathin TiO2 precoating layer with a thickness ca. 2 nm acts as a crucial interlayer that facilitates the growth of well-organized MnO2 nanosheets onto the surface of the titania-carbon nanofibers. Due to the interweaved network structures of the carbon nanofibers and the increased content of the immobilized MnO2, the exfoliation and aggregation, as well as the large volume change of the MnO2 nanosheets, are significantly inhibited; thus, the MnO2-TiO2-carbon electrodes displayed outstanding cycling performance and a reversible rate capability during the Li+ insertion/extraction processes. [ABSTRACT FROM AUTHOR]

A hierarchical H 3 PW 12 O 40 /TiO 2 nanocomposite as well as a H 3 PW 12 O 40 /TiO 2 /cellulose composite membrane were fabricated with cellulose substance (e.g. , ordinary laboratory filter paper) as scaffold, showing significant photocatalytic performances towards the photocatalytic degradation of organic dyes under UV irradiation and outdoor sunlight, respectively. [Display omitted] • Nanotubular H 3 PW 12 O 40 /TiO 2 composites were prepared with cellulose as scaffold. • The impregnation and layer-by-layer methods were employed and compared. • The nanocomposites showed enhanced photocatalytic degradation performances. • A H 3 PW 12 O 40 /TiO 2 /cellulose composite sheet was used as a photocatalytic membrane. • The composite sheet showed excellent performances directly under outdoor sunlight. By applying the natural cellulose substance (e.g. , ordinary laboratory filter paper) scaffold as the structural template, a series of nanotubular H 3 PW 12 O 40 /TiO 2 (HPW/TiO 2) composites with various contents of the H 3 PW 12 O 40 component were fabricated, which perfectly inherited the hierarchically porous network structure of the original cellulose substance. The optimal HPW/TiO 2 nanocomposite with a H 3 PW 12 O 40 content of 15.6 wt% delivered an apparent rate constant of 0.54 min−1 towards the photocatalytic degradation of methylene blue (initial concentration: 10.0 mg L−1) under UV light, revealing an increment of 1.9 times in comparison with the pure TiO 2 nanotubes sample. Moreover, when the cellulose scaffold was served as a support, the obtained HPW/TiO 2 /cellulose composite sheet exhibited excellent photocatalytic performance as a photocatalytic membrane for the photocatalytic degradation of organic pollutants directly under outdoor sunlight. Thanks to the three-dimensionally interwoven structures and the compact contact in-between the H 3 PW 12 O 40 and TiO 2 phases, the hierarchical HPW/TiO 2 nanocomposites and the HPW/TiO 2 /cellulose composite sheet represented outstanding and recyclable photocatalytic performances. The possible photocatalytic mechanism was investigated to demonstrate that the photo-induced holes dominated the photocatalytic reaction. [ABSTRACT FROM AUTHOR]

A train of bio-inspired nanotubular Na2MoO4/TiO2 composites were synthesized by using a natural cellulose substance (e.g., commercial ordinary filter paper) as the structural template. The TiO2 gel films were coated on the cellulose nanofiber surfaces via a sol-gel method firstly, followed with the deposition of the poly(diallyldimethylammonium chloride)/Na2MoO4 (PDDA/Na2MoO4) bi-layers several times, through the layer-by-layer self-assembly route, yielding the (PDDA/Na2MoO4)n/TiO2-gel/cellulose composite, which was calcined in air to give various Na2MoO4/TiO2 nanocomposites containing different Na2MoO4 contents (15.4, 24.1, and 41.4%). The resultant nanocomposites all inherited the three-dimensionally porous network structure of the premier cellulose substance, which were formed by hierarchical TiO2 nanotubes anchored with the Na2MoO4 layers. When employed as anodic materials for lithium-ion batteries, those Na2MoO4/TiO2 nanocomposites exhibited promoted electrochemical performances in comparison with the Na2MoO4 powder and pure TiO2 nanotubes, which was resulted from the high capacity of the Na2MoO4 component and the buffering effects of the TiO2 nanotubes. Among all the nanotubular Na2MoO4/TiO2 composites, the one with a Na2MoO4 content of 41.4% showed the best electrochemical properties, such as the cycling stability with a capacity of 180.22 mAh g−1 after 200 charge/discharge cycles (current density: 100 mA g−1) and the optimal rate capability. [ABSTRACT FROM AUTHOR]

A filter-paper-derived nanofibrous silica–carbon composite composed of thin silica layer conformally coated on carbon nanofibers is synthesized by employing natural cellulose substance (ordinary laboratory filter paper) as both scaffold and carbon source. When the nanocomposite is employed as an anode material for lithium-ion batteries, it displays improved lithium-ion storage performance compared with the bare silica and carbon counter materials, due to the unique three-dimensional porous network structures of the carbon fiber scaffold and the thin silica layer. For the silica–carbon nanocomposite with 31.2 wt% of silica content and the silica layer with a thickness of ca. 60 nm, it delivers a stable discharge capacity of ca. 400 mAh g −1 after 200 discharge/charge cycles at a current density of 100 mA g −1 . Moreover, improved electrochemical performances are achieved by coverage of an additional carbon layer or deposition of silver nanoparticles onto the silica–carbon nanofibers, which exhibits specific capacities of 488.7 and 477.5 mAh g −1 after 100 discharge/charge cycles, respectively. The current synthetic method provides a facile and low-cost strategy for the large-scale production of nanofibrous silica–carbon based composites as anodic materials for lithium-ion batteries. [ABSTRACT FROM AUTHOR]

Nanoarchitectures based on the layer-by-layer self-assembly technique hold great potential for the availability and applicability of bio-inspired functional materials. The introduction of various specific functional building blocks onto the nanofibers of natural cellulose substances (e.g., commercial filter paper, cotton, etc.) through the self-assembly approach provides a facile strategy for the fabrication of artificial nanomaterials. This review summarizes a series of cellulose-based catalytic materials fabricated by utilizing the natural cellulose substance as the structural scaffolds or templates through the LbL self-assembly process. The unique three-dimensional network porous structures and high surface areas of the cellulose substances were maintained by the resultant cellulose-derived catalysts, while the excellent mechanical strength of the cellulose-based membrane catalysts was inherited from the initial cellulose substrates. When employed for the photodegradation of organic dyes, the photocatalytic hydrogen production from water splitting, and the antibiosis, these cellulose-based catalysts exhibited high activities and excellent cycling stabilities. [Display omitted] • The layer-by-layer self-assembly method is utilized for the fabrication of natural cellulose-based catalysts. • The unique structural features of the natural cellulose substances lead to improved catalytic activities. • The self-assembly approach holds great potential for the development of high-performance catalysts. [ABSTRACT FROM AUTHOR]

A bio-inspired nanofibrous Co 3 O 4 /TiO 2 /carbon composite was fabricated using natural cellulose substrate (laboratory filter paper) as both the carbon source and the structural scaffold. Employing a surface sol–gel process to form a thin TiO 2 gel layer coating on each cellulose nanofiber of the filter paper, the resulted composite sheet was successively carbonized in inert atmosphere to give a nanofibrous TiO 2 /carbon composite; afterwards, nano-sized Co 3 O 4 particles (10–30 nm) were uniformly deposited onto the yielded composite fibers via a simple hydrothermal method, resulting in the Co 3 O 4 /TiO 2 /carbon hybrid. The ternary composite possessed a unique hierarchically three-dimensional porous structure which inherited precisely from the initial filter paper. This special structure with the internal conductive carbon fiber and the external nano-sized Co 3 O 4 particles offered the nanocomposite with an excellent electrochemical performance as anodic material for lithium-ion batteries. The optimal sample with a Co 3 O 4 mass content of 50.6% delivered an initial discharge capacity of 1239 mAh g−1 at a current density of 100 mA g−1, which was far exceeded the theoretical capacity of Co 3 O 4. The extra capacity is ascribed to the additional lithium storage sites provided by the large specific surface area of the composite, and the formation of the solid electrolyte interface (SEI) layer in the initial discharge process causing a large consumption of Li+ which results in some irreversible capacity. And after 200 discharge/charge cycles, a high reversible capacity of 764 mAh g−1 was maintained, which is higher than most of the Co 3 O 4 /carbon hybrid materials reported. This work provided a simple and efficient strategy for designing and preparing nanoscale metal-oxide/carbon composite material with considerable potential in energy storage and conversion. Nanofibrous Co 3 O 4 /TiO 2 /carbon composite derived from cellulose substance was fabricated, showing enhanced electrochemical performances as an anodic material for lithium-ion batteries. Image 1 • A cellulose derived nanofibrous Co 3 O 4 /TiO 2 /carbon composite was fabricated. • Nanosized Co 3 O 4 particles were coated uniformly on the nanofiber surfaces. • The composite possessed a unique hierarchically porous net work structure. • It exhibited superior electrochemical performances as anodic material for LIBs. [ABSTRACT FROM AUTHOR]

• A bio-inspired nanofibrous activated-carbon/sulfur composite was fabricated. • The sublimed sulfur was uniformly impregnated in the micro/mesopores of the activated carbon. • The nanocomposite showed enhanced electrochemical performances as a cathodic material. A nanofibrous activated carbon with high surface area was fabricated via the alkali activation process by using the natural cellulose substance (i.e. common laboratory filter paper) as both the structural support and carbon source. The obtained nanofibrous activated carbon was used as a host to further impregnated with sulfur to form the activated-carbon/sulfur composites for lithium-sulfur (Li-S) batteries. The activated-carbon/sulfur composite with a sulfur content of 49.4 wt% exhibited an initial discharge capacity of 1393 mA h g−1 and stabilized at 576 mA h g−1 at a current rate of 0.1 C after 100 cycles. And a good rate capability with a reversible capacity of 789 mA h g−1 was obtained at 0.1 C after 100 charge/discharge cycles. The improvements of the cycling stability and rate capability of the activated-carbon/sulfur composites are attributed to the unique three-dimensional conductive network structures and the high surface area of the nanofibrous activated carbon scaffolds, which not only effectively restrain the dissolution and diffusion of the polysulfide during the discharge process, as well as accommodate the large volume expansion in the formation process of S to Li 2 S in the lithium-sulfur batteries. [ABSTRACT FROM AUTHOR]