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[Display omitted] • An ultra-fast humidity sensor based on C 60 -OH/PDDA/SiO 2 composite is proposed. • A human-machine interface based on an ultra-fast humidity sensor is presented for assisting aphasia patients with semantic expressions. • This interface is particularly suitable for aphasic patients with limited physical mobility. Communication between aphasic patients and health care professionals (HCPs) is often difficult, which is even more complex for aphasic patients with limited physical mobility. In this study, we have proposed a C 60 -OH/PDDA/SiO 2 -based humidity sensor with an extremely short response/recovery time (13 ms/30 ms). This is closely related to the electrostatic adsorption of PDDA which effectively alleviates the aggregation of C 60 -OH and the introduction of SiO 2 microspheres which increases the diffusion space of water molecules. The fast response and recovery rates gave the sensor good respiratory monitoring capability, which can be used to develop a human–machine interface (HMI) to assist aphasic patients for semantic expression. In this HMI, aphasia patients can generate different respiratory signals through the ultrafast humidity sensors to express specific semantics (such as thirst, hunger, etc.). In contrast to traditional semantic expression devices, this interface does not require the user to have vocal or physical movement, and therefore is extremely friendly to aphasic patients with limited mobility. [ABSTRACT FROM AUTHOR]

• We develop a novel chemical method for the surface encapsulation of hydrogel with elastic coating that can prevent hydrogel from de/hydration in air and water. • Our mothed shows multiple applicability, which is applicable not only for flat surface of hydrogels, but also various irregular shapes including tubes, spheres, and wrinkles of hydrogels. • Our mothed can improve the functionality of hydrogel sensors, making them capable of long-term sensitivity in both air and water systems. De/hydration is unavoidable for unencapsulated hydrogels, which would weaken their physical performance during applications. Herein, we report a surface-encapsulating method that can chemically make an elastic coating at the surface of hydrogel to prevent it from de/hydration in air and water. The water loss is less than 6 wt% in weight by keeping the surface-encapsulated hydrogel in air at 28 °C for 20 days, and its weight doesn't increase by immersing it in water for 60 days. The adhesion energy between hydrogel and the coating reaches 2000 J/m2, so that it can keep the structural integrity in response to repeated stretching, compression, bending, twisting, and knotting. This method doesn't require any templates and special devices, which can make surface encapsulation for hydrogels that have irregular shapes such as tubes, spheres, and wrinkles. The encapsulated elastic coating is of long-term (180 days) stability without interfacial failure in air, and in acidic, alkaline, and salt solutions, which enables the hydrogel capable of long-term sensitivity as a strain sensor in air and water systems, showing great potential for signal transmission under water. [ABSTRACT FROM AUTHOR]

[Display omitted] • Unclonable plasmonic security labels with multiscale random features are designed for high encoding capacity. • A robotic wet-chemical system is invented for mass-produced fabrication. • Plasmonic nanostructures and random features are variously modulated by in situ substrate growth. Plasmonic physical unclonable function (PUF) labels have been proven to be an effective anti-counterfeiting strategy, but their high tunability and multi-encoded capabilities remain to be explored for higher encoding capacity (EC). Herein, the PUF labels with high security level are prepared, which are constructed by the micro-domains of plasmonic nanostructures. The micro-domains are formed by mask-assisted ultraviolet (UV) exposure and 50 nm gold nanoparticles (Au NPs) electrostatic adsorbed on the unexposed area. And a robotic wet-chemical system is invented to modulate the in situ epitaxial growth of Au NPs by programming the growth conditions for human-free preparation and mass production. Three random processes, including mask-assisted UV photochemical reaction, electrostatic self-assembly, and in situ epitaxial growth, make sure multiscale random features. Thus, two-dimensional views with different resolutions can be obtained by three random optical imaging signals-bright field (BF), Raman imaging (RI), and dark field (DF), and the random signals will change with the modulation methods, leading to higher EC. Through analyzing the random features, a robust image authentication system is built, and the EC is calculated as 1.8 × 104966 in a 50 × 50 μm2 domain for each modulation method. [ABSTRACT FROM AUTHOR]

• Ultrathin separator (15 µm) was fabricated via solution-phase inversion technique. • The separator exhibited higher tensile strength (74.5 MPa) and porosity (66.7%). • The separator showed superior electrochemical performance to commercial separators. The thickness of separators has a great influence on electrochemical performance and battery safety. However, the solution for the inevitable trade-off between separators thickness and their performance still remains a great challenge. Herein, we report novel strategy for manufacturing ultrathin cellulose membrane as separator for high-performance supercapacitors (SCs) via a low-cost and scalable solution-phase inversion technique. The ultrathin cellulose separator with a thickness of 15 µm possessed excellent physical performances, including higher tensile strength (74.5 MPa) and porosity (66.7%), ensuring safety during assembly and operation of the device. Simultaneously benefiting from the substantial polar hydroxyl groups (–OH) and inter- and intra-molecular hydrogen bonds in the cellulose structure, cellulose separator directly realized better electrolyte affinity, thermal stability, and chemical stability in contrast with commercial separators. The ultrathin construction of the separator shortened ion transport pathways, reduced the internal resistance and increased the ion conductivity, which would facilitate fast ion transport for the practical application of separator. Our methods provided a much-needed strategy for fabrication of ultrathin separators and might promote the development of portable energy storage devices. [ABSTRACT FROM AUTHOR]

[Display omitted] • Introduction of Cu loading to the conventional lean NO x trap catalyst. • Poor performance of Cu-loaded one-body catalysts owing to Pt-Cu complex formation. • Highest performance for the physical mixture of Pt catalyst and Cu-loaded adsorbent. • Improved NO x storage and reduction performance at 150 ℃ using the new LNT catalyst. Lean NO x trap (LNT) used in diesel-powered vehicles exhibit poor NO x storage and reduction (NSR) performance during low-temperature operation, particularly under cold-start conditions. To overcome this limitation, Cu was added to a conventional LNT catalyst (Pt-Ba/γ-Al 2 O 3 , PBA) to improve the NO x storage and regeneration performance of the Cu-loaded Ba adsorbent (Cu-Ba/γ-Al 2 O 3) during low-temperature operation. However, a Pt-Cu complex was formed when Pt and Cu were used together as a one-body catalyst (Pt-Cu-Ba/γ-Al 2 O 3 , PCBA), leading to decreased catalytic performance. Physical mixing was investigated as a method to prevent the catalytic performance degradation caused by the Pt-Cu complex. The physical mixture of Pt/γ-Al 2 O 3 and Cu-Ba/γ-Al 2 O 3 (PA + CBA) could prevent the formation of Pt-Cu complex and yielded the highest NSR performance at 150 ℃ among the synthesized LNT catalysts. PA + CBA maintained a significantly improved NSR performance in lean-rich cycling tests using CO or H 2 as a reducing agent. [ABSTRACT FROM AUTHOR]

[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]

[Display omitted] • Structural color-based PUF labels (SCPLs) labels fabricated by colloidal crystals for anti-counterfeiting. • SCPLs exhibit low optical loss and accomplish the safety and practicability of optical PUF labels. • Hiding function of SCPLs prevent the information of SCPL from being leaked. • A high-security mutual authentication system for supply chain realized by SCPLs. Optical physical unclonable functions (PUFs) have been considered to be one of the powerful tools to curb counterfeiting due to the unpredictable preparation process and identifiable information content. Responsive colloidal photonic crystals capable of controlling and manipulating light propagation exhibit low optical loss, stability and hiding function, which are more suitable to accomplish the safety and practicability of optical PUF labels. Herein, structural color-based PUF labels (SCPLs) prepared by injection-casting colloidal crystals propose a highly efficient and stable PUF authentication. With the decimal encode of the reflection intensity level at each pixel, the SCPL can achieve a theoretical encoding capacity of 102500 at 50 × 50 pixels. Utilizing the responsiveness of SCPLs, the PUF features can be switched between invisible and visible states to hide PUF information. Moreover, authentication experiments confirmed that the robustness of SCPL reached 0.994 and 0.960 in tensile test and wetting–drying cycle test, respectively, indicating that SCPL with hiding function, low optical loss and stability can be authenticated multiple times in practical applications. Interestingly, a high-security mutual authentication system for supply chain based on digital storage secret keys is proposed to showcase the strong application potential of SCPLs for various fields such as confidentiality of materials/technologies, dynamic anti-counterfeiting/camouflage, etc. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel phosphine oxide-containing hyperbranched polyol was synthesized. • RPUF containing POCHP and EG exhibit excellent fire safety and physical properties. • The production of CO and NO x during combustion of RPUF are significantly decreased by combination of POCHP and EG. In this work, a novel phosphine oxide-containing hyperbranched polyol (POCHP) was synthesized. Then POCHP and/or expandable graphite (EG) were incorporated into rigid polyurethane foam (RPUF). EG increases foam density and deteriorates compressive strength and thermal conductivity, but POCHP has opposite effects. A 12.8% improvement of compressive strength and slightly decreased density and thermal conductivity are achieved by ERPUF50 containing POCHP and EG. And it reaches a limited oxygen index of 30.0% and UL-94 V-0 rating with immediate self-extinguishing behavior after removing flame. The peak heat release rate, total heat release and total smoke production of ERPUF50 are reduced by 71.1%, 52.2% and 71.1% respectively via bi-phase flame retardant mechanisms. Interesting phenomena were observed that POCHP promotes the intumescence of EG after combustion. The results of combustion gas analysis reveal that single POCHP or EG reduces the production of CO but increases the generation of NO x. ERPUF50 exhibits a 52% decrement of CO and an unexpected 40% diminishment of NO x. ERPUF50 with excellent comprehensive properties can not only be used as fire safe thermal insulation material with high physical performances, but also significantly reduce the release of contaminative smoke, CO and NO x in fires and waste RPUF disposal by combustion. [ABSTRACT FROM AUTHOR]

• The exploration of MXenes-like WO 3 architecture with perfectly multilayer features. • Deeply understanding on the growth mechanism of MXenes-like WO 3 architecture. • The overall excellent photoelectrochemical performance of WO 3 architecture. Currently, the multilayer architecture is recognized as one of shining stars with exciting applications in environment and catalysis, energy storage/conversion, optoelectronics and so forth. However, different to the typical MXenes, the fabrication of layered transition metal oxides is still a grand challenge, since they are highly difficult to be exfoliated into multilayered structures, owing to their intrinsically strong covalent bond. Here, we report the controlled growth of MXenes-like WO 3 architecture in the families of transition metal oxides with perfectly multilayered features, by tailoring the formation of precursor WO 3 ·H 2 O based on the competition between the concentrations of WO 4 2− and anions (NO 3 –, Cl−) within the solution. The as-built multilayer WO 3 architecture has overall superior physical performance to conventional solid counterparts, and exhibits a remarkable photocurrent density of 2.3 mA cm−2 at 1.23 vs. RHE under AM 1.5G illumination, which is the highest one among those of WO 3 photoanodes without cocatalysts/dopants in neutral solution ever reported. [ABSTRACT FROM AUTHOR]

[Display omitted] • We report intrinsically stretchable, self-healable, photodegradable supercapacitor. • The supercapacitor is fabricated with a supramolecular Azo-PAM/α-CDP composite. • The supercapacitor is mechanically stable when stretched by 50% over 500 times. • Self-healing efficiency of the supercapacitor is ≈90% after 5 self-healing cycles. • The supercapacitor photodegrades and dissolves in water by 365 nm UV light irradiation. We report on the fabrication of a high performance multi-functional supercapacitor which is intrinsically stretchable, self-healable, and photodegradable. A repeatedly stretchable (500 times), photodegradable hydrogel that self-heals quickly at room temperature without any trigger is synthesized by crosslinking of azobenzeno-polyacrylamide (Azo-PAM) and water-soluble α-cyclodextrin polymer (α-CDP) via dynamic host-guest interaction. With the Azo-PAM/α-CDP/LiCl hydrogel as polyelectrolyte, the stretchable, self-healable, and photodegradable supercapacitor is fabricated. After complete bisection, the supercapacitor recovers its electrochemical performance by physical contact in air-ambient conditions and maintains its performance upon multiple cycles of self-healing at a single bisected location. It also maintains elastic performance even after repeated stretching and self-healing. Finally, the supercapacitor exhibits photodegrading performance, dissolving in water upon UV-irradiation after use. This work demonstrates the superior performance and high potential of our newly devised stretchable, self-healable, and photodegradable supercapacitor as a smart energy storage device for next-generation durable and eco-friendly wearable electronics. [ABSTRACT FROM AUTHOR]

[Display omitted] • Thermal-acidic-modified kaolin (TAMK) is an inorganic coagulant. • TAMK acts as a physical-chemical conditioner in sludge dewatering. • SiO 2 and Al3+ are the main elements of TAMK in sludge dewatering. • TAMK is competitively priced for inorganic coagulant. In this study, the effect of thermal-acidic-modified kaolin (TAMK) on waste activated sludge (WAS) conditioning and dewatering was investigated for the first time. Using analyses of XRD, XRF, FT-IR, porosity and specific surface area, structural changes of kaolin were evaluated before and after modification. Conditioning with TAMK reduced the specific resistance to filterability (SRF) and time to filter (TTF), capillary suction time (CST) of WAS to 91.2%, 73.1% and 70.8% respectively. WAS conditioning with TAMK resulted in reducing compressibility and increasing filtration yield, the porosity of WAS, that indicating its function as a physical conditioner (skeleton builder). TAMK increased the WAS particle size significantly (from 47.8 μm to 451 μm) and improved their resistance against shear force. TAMK decreased the bound water (58.1%), negative zeta potential (from −31.4 mV to −7.2 mV) and EPS (extracellular polymeric substances) of WAS, indicating its function as a chemical conditioner. This study showed that TAMK acts as a physical-chemical conditioner. Also, the estimated costs of WAS conditioning with TAMK is 35.22 $/ton dry solids (DS). In general, TAMK is an affordable, inexpensive and effective option for sludge conditioning and dewatering. [ABSTRACT FROM AUTHOR]

• A MultiFunctional Geoengineering material (MFG) was developed to tackle eutrophication. • Capping treatment by MFG turns sediment from a nutrient (P and N) source to a sink. • O 2 nanobubbles delivered from MFG reverses hypoxia and reduces nutrient loads. • MFG functions as physical capping, nutrient absorber, and delivers O 2. • Contribution of each function on control of internal nutrient loads was quantified. An effective approach for control of internal nutrient loading and sediment hypoxia remains a longstanding challenge to the restoration of aquatic ecosystems. In order to simultaneously tackle these issues, a MultiFunction Geoengineering material (MFG) was developed for sediment remediation through the synergistic functions of physical capping, nutrient adsorption and delivery of O 2 nanobubbles. The MFG, derived from natural zeolite, exhibited superior (1.5–4 times higher) adsorption capabilities for both phosphate (PO 4 3−-P) and ammonium (NH 4 +-N), than pristine zeolite. The O 2 adsorption capacity was also enhanced from 46, observed in the natural zeolite, to 121 mg O 2 /g for the MFG. An in-situ sediment capping experiment in a eutrophic lake demonstrated that the application of MFG dramatically reversed sediment hypoxia (ORP −200 mV) to an aerobic status (ORP 175 mV) and, furthermore, stimulated sediment microbial activity, particularly nitrifying bacteria. The MFG treatment resulted the sediment changing from a nutrient source to a sink through decreasing the cumulative PO 4 3−-P and NH 4 +-N fluxes from the sediment by 124.6% and 131.1%, respectively. Moreover, the comprehensive functionalities of the material have been, for the first time, quantified, from which data O 2 nanobubble delivery was determined to be the largest contributor, reducing the fluxes of PO 4 3−-P and NH 4 +-N by 57.3% and 56.1% of, respectively. Our findings highlight the viability of such multifunctional material for the remediation of internal nutrient loads in lacustrine environments, towards sustainable eutrophication control. [ABSTRACT FROM AUTHOR]