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Cellulose aerogels are plagued by intermolecular hydrogen bond-induced structural plasticity, otherwise rely on chemicals modification to extend service life. Here, we demonstrate a petrochemical-free strategy to fabricate superelastic cellulose aerogels by designing hierarchical structures at multi scales. Oriented channels consolidate the whole architecture. Porous walls of dehydrated cellulose derived from thermal etching not only exhibit decreased rigidity and stickiness, but also guide the microscopic deformation and mitigate localized large strain, preventing structural collapse. The aerogels show exceptional stability, including temperature-invariant elasticity, fatigue resistance (∼5 % plastic deformation after 10

The oriented pore structure of wood endows it with a variety of outstanding properties, among which the low thermal conductivity has attracted researchers to develop wood-like aerogels as excellent thermal insulation materials. However, the increasing demands of environmental protection have put forward new and strict requirements for the sustainability of aerogels. Here, we report an all-natural wood-inspired aerogel consisting of all-natural ingredients and develop a method to activate the surface-inert wood particles to construct the aerogel. The obtained wood-inspired aerogel has channel structure similar to that of natural wood, endowing it with superior thermal insulation properties to most existing commercial sponges. In addition, remarkable fire retardancy and complete biodegradability are integrated. With the above outstanding performances, this sustainable wood-inspired aerogel will be an ideal substitute for the existing commercial thermal insulation materials.

Soft matter catalyst system allowing controllable manipulation of the organized nanostructure and surface property holds the potential for renewable energy. Here we demonstrate the construction of a continuously regenerative hydrogel photocatalyst that confines the metal-thiolate coordination induced nanocavity into robust micro-sized spongy network for water splitting. Thanks to low vaporization enthalpy and fast proton mobility of water molecules confining in nanocavities, the composite delivers outstanding photocatalytic H

We report that continuous MOF films with highly controlled thickness (from 44 to 5100 nm) can be deposited over length scales greater than 80 centimeters by a facile, fast, and cost-effective spray-coating method. Such success relies on our discovery of unprecedented perfectly dispersed colloidal solutions consisting of amorphous MOF nanoparticles, which we adopted as precursors that readily converted to the crystalline films upon low-temperature in situ heating. The colloidal solutions allow for the fabrication of compact and uniform MOF films on a great deal of substrates such as fluorine-doped tin oxide, glass, SiO2 , Al2 O3 , Si, Cu, and even flexible polycarbonate, widening their technological applications where substrates are essential. Despite the present work focuses on the fabrication of uniform cobalt-(2-methylimidazole)2 and zinc-(2-methylimidazole)2 films, our findings mark a great possibility in producing other high-quality MOF thin films on a large scale.

The anode oxygen evolution reaction (OER) is known to largely limit the efficiency of electrolyzers owing to its sluggish kinetics. While crystalline metal oxides are promising as OER catalysts, their amorphous phases also show high activities. Efforts to produce amorphous metal oxides have progressed slowly, and how an amorphous structure benefits the catalytic performances remains elusive. Now the first scalable synthesis of amorphous NiFeMo oxide (up to 515 g in one batch) is presented with homogeneous elemental distribution via a facile supersaturated co-precipitation method. In contrast to its crystalline counterpart, amorphous NiFeMo oxide undergoes a faster surface self-reconstruction process during OER, forming a metal oxy(hydroxide) active layer with rich oxygen vacancies, leading to superior OER activity (280 mV overpotential at 10 mA cm-2 in 0.1 m KOH). This opens up the potential of fast, facile, and scale-up production of amorphous metal oxides for high-performance OER catalysts.

Energy efficient buildings require materials with a low thermal conductivity and a high fire resistance. Traditional organic insulation materials are limited by their poor fire resistance and inorganic insulation materials are either brittle or display a high thermal conductivity. Herein we report a mechanically resilient organic/inorganic composite aerogel with a thermal conductivity significantly lower than expanded polystyrene and excellent fire resistance. Co-polymerization and nanoscale phase separation of the phenol-formaldehyde-resin (PFR) and silica generate a binary network with domain sizes below 20 nm. The PFR/SiO2 aerogel can resist a high-temperature flame without disintegration and prevents the temperature on the non-exposed side from increasing above the temperature critical for the collapse of reinforced concrete structures.

Nanostructured metal sulfide-amine hybrid materials have attracted attention because of their unique properties and versatility as precursors for functional inorganic nanomaterials. However, large-scale synthesis of metal sulfide-amine hybrid nanomaterials is limited by hydrothermal and solvothermal preparative reaction conditions; consequently, incorporation of such materials into functional nanomaterials is hindered. An amine molecule-assisted refluxing method was used to synthesize highly uniform zinc sulfide⋅(diethylenetriamine)0.5 (ZnS⋅(DETA)0.5 ) hybrid nanosheets and nanobelts in a large scale. The obtained ZnS⋅(DETA)0.5 hybrid nanomaterials can be used as efficient precursors to fabricate functional ZnS nanomaterials and carbon encapsulated sulfur (S@C) nanocomposite cathodes for Li-S batteries.

Co-based nanomaterials have been intensively explored as promising noble metal free oxygen evolution reaction (OER) electrocatalysts. Herein, we first report phase selective synthesis of novel hierarchical CoTe2 and CoTe nanofleeces for efficient OER catalyst. The CoTe2 nanofleeces exhibited excellent electrocatalytic activity and stablity for OER in alkaline media. It has been discovered that the CoTe2 catalyst exhibited superior OER activity to the CoTe catalyst and comparable to the state-of-the-art RuO2 catalyst. Density functional theory calculations showed that the binding strength and lateral interaction of the reaction intermediates on CoTe2 and CoTe are essential for the order of their overpotential and the trend variation at different condition. This study provides value insights for rational design of noble metal free OER catalysts with high performance and low cost by use of Co-based chalcogenides.

Improving the efficiency of electron-hole separation and charge-carrier utilization plays a central role in photocatalysis. Herein, Pt nanoparticles of ca. 3 nm are incorporated inside or supported on a representative metal-organic framework (MOF), UiO-66-NH2 , denoted as Pt@UiO-66-NH2 and Pt/UiO-66-NH2 , respectively, for photocatalytic hydrogen production via water splitting. Compared with the pristine MOF, both Pt-decorated MOF nanocomposites exhibit significantly improved yet distinctly different hydrogen-production activities, highlighting that the photocatalytic efficiency strongly correlates with the Pt location relative to the MOF. The Pt@UiO-66-NH2 greatly shortens the electron-transport distance, which favors the electron-hole separation and thereby yields much higher efficiency than Pt/UiO-66-NH2 . The involved mechanism has been further unveiled by means of ultrafast transient absorption and photoluminescence spectroscopy.

All-inorganic cesium lead-halide perovskite nanocrystals have emerged as attractive optoelectronic nanomaterials owing to their stabilities and highly efficient photoluminescence. Herein we report a new type of highly luminescent perovskite-related CsPb2 Br5 nanoplatelets synthesized by a facile precipitation reaction. The layered crystal structure of CsPb2 Br5 promoted an anisotropic two-dimensional (2D) crystal growth during the precipitation process, thus enabling the large-scale synthesis of CsPb2 Br5 nanoplatelets. Fast anion exchange has also been demonstrated in as-synthesized CsPb2 Br5 nanoplatelets to extend their photoluminescence spectra to the entire visible spectral region. The large-scale synthesis and optical tunability of CsPb2 Br5 nanoplatelets will be advantageous in future applications of optoelectronic devices.

Resorcinol-formaldehyde (RF) and graphene oxide (GO) aerogels have found a variety of applications owing to their excellent properties and remarkable flexibility. However, the macroscopic and controllable synthesis of their composite gels is still a great challenge. By using GO sheets as template skeletons and metal ions (Co(2+), Ni(2+), or Ca(2+)) as catalysts and linkers, the first low-temperature scalable strategy for the synthesis of a new kind of RF-GO composite gel with tunable densities and mechanical properties was developed. The aerogels can tolerate a strain as high as 80% and quickly recover their original morphology after the compression has been released. Owing to their high compressibility, the gels might find applications in various areas, for example, as adsorbents for the removal of dye pollutants and in oil-spill cleanup.

Recently, porous hydrophobic/oleophilic materials (PHOMs) have been shown to be the most promising candidates for cleaning up oil spills; however, due to their limited absorption capacity, a large quantity of PHOMs would be consumed in oil spill remediation, causing serious economic problems. In addition, the complicated and time-consuming process of oil recovery from these sorbents is also an obstacle to their practical application. To solve the above problems, we apply external pumping on PHOMs to realize the continuous collection of oil spills in situ from the water surface with high speed and efficiency. Based on this novel design, oil/water separation and oil collection can be simultaneously achieved in the remediation of oil spills, and the oil sorption capacity is no longer limited to the volume and weight of the sorption material. This novel external pumping technique may bring PHOMs a step closer to practical application in oil spill remediation.

Ultrathin and ultralong: Highly uniform, ultrathin (diameter 5-7 nm), and ultralong (aspect ratio >10(4)) PtPdTe nanowires (NWs) were synthesized by using a facile method employing Te NWs as both sacrificial templates and reducing agents. Fine-tuning of the molar ratios of Pt and Pd precursors afforded PtPdTe NWs with different compositions and enhanced electroactivity in the methanol oxidation reaction in comparison with a commercial Pt/C catalyst.

Playing six-a-side: Complex hexagonal prism Cu(1.94)S-ZnS heteronanostructures were synthesized by a colloidal route. Cu(1.94)S-ZnS, Cu(1.94)S-ZnS-Cu(1.94)S, and Cu(1.94)S-ZnS-Cu(1.94)S-ZnS-Cu(1.94)S structures are formed with screw-, dumbbell-, and sandwich-like shapes by using CuI and [Zn(S(2)CNEt(2))(2)] as precursors in oleylamine.

Hydrogels and aerogels are two typical families of gels, classified according to the medium they encompass, that is, water and air, respectively. Hydrogels have not only pervaded our everyday life in a variety of forms (e.g., fruit jellies, toothpaste, contact lenses, and hair gel), but have also been extensively explored as functional soft materials for use in various scientific fields. Replacing the liquid solvent in hydrogels or other wet gels by air without collapsing the network structure can lead to a new type of porous materials, namely, aerogels. Particularly, 3D nanoscale networks with open pores in the gels allow access and fast diffusion of ions and molecules, and thus hydrogels/aerogels have exhibited excellent performance as super adsorbents, electrode materials for batteries and supercapacitors, catalyst supports, and chemical and biological sensors. Despite their outstanding potential, several challenges in aerogel synthesis still must be addressed prior to their extensive practical application. The major problem associated with conventional aerogels is poor mechanical stability. The mechanical strength of aerogels could be enhanced by nanocasting conformal polymer coatings on preformed 3D networks, but this was accompanied by dramatic decreases in their porosity. Furthermore, to prevent the network from collapsing in a gel, supercritical drying is the most widely used technique for solvent removal. It is difficult to prepare low-cost aerogels on a large scale due to the limitations of industrial supercritical drying. Although several nanomaterials including carbon nanotubes, cellulose nanofibers, and the newly discovered graphene have been recently used as building blocks and assembled into monolithic gels, there is a lack of precise control of their physicochemical properties, particularly the size of building blocks, the porosity, and their surface chemistry, which are crucial in the further design and functionalization of aerogels for various applications. Here we report a new class of monolithic hydrogels/aerogels consisting of highly uniform carbonaceous nanofibers (CNFs), based on the recent, well-developed templatedirected hydrothermal carbonization (HTC) process. Compared with the conventional process for aerogel preparation, our synthetic method has some significant advantages: 1) Direct scaleup from 30 mL to 12 L just by using a large autoclave and without changing reactant concentrations and reaction time; 2) Easy and precise control of the structural parameters and mechanical strength of the CNF hydrogels/ aerogels over a wide range; and 3) Extraordinary flexibility and high chemical reactivity of the CNF gels give them great application potential. The synthesis of CNF gels is illustrated in Figure 1a. Ultrathin Te nanowire (TeNWs) templates are first dispersed in glucose solution to form a homogenous mixture (step 1 in Figure 1a). Hydrothermal treatment of the mixture at 180 8C for 12–48 h results in a mechanically robust monolithic gel-like product, which occupies the whole Teflon container and can be taken out directly without any damage (step 2 in Figure 1a; see also Supporting Information Figure S1a). The as-prepared wet gel can be easily cut into the desired shape (Supporting Information Figure S1b). After washing and chemical etching to remove TeNWs (Supporting Information Figure S2), the CNF hydrogel is formed (step 3 in Figure 1a). To obtain the CNF aerogel, water in the hydrogel is removed by freeze-drying (step 4 in Figure 1a and Supporting Information Figure S1c). A low-magnification SEM image of the aerogel reveals a highly porous network structure consisting of disordered nanofibers with uniform size (Figure 1c, left). There is no apparent difference in CNF size and distribution over the whole monolithic gel (Supporting Information Figure S3), that is, the network structure is homogeneous. Further SEM observations indicate that these highly uniform nanofibers interconnect with each other to a high degree through numerous junctions (Figure 1c, right). We hypothesize that these junctions are responsible for the outstanding mechanical properties of the gels. Formation of junctions between CNFs is not difficult to understand. In the original mixture before hydrothermal treatment, it was unavoidable that the TeNWs physically contacted or approached each other if their concentration reached a critical [*] Dr. H. W. Liang, Q. F. Guan, L. F. Chen, Z. Zhu, W. J. Zhang, Prof. S. H. Yu Division of Nanomaterials and Chemistry, Hefei National Laboratory for Physical Sciences at Microscale, Department of Chemistry, National Synchrotron Radiation Laboratory, University of Science and Technology of China Hefei, Anhui 230026 (China) E-mail: shyu@ustc.edu.cn Homepage: http://staff.ustc.edu.cn/~ yulab/

A Pd-Au/CuO@Cu heterostructured nanoparticle tube catalyst is synthesized by a one-step electrodeposition route onto an anodic aluminium oxide template in anhydrous DMSO, and characterized by powder XRD, SEM, TEM, XPS, and cyclic voltammetry.