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Active compounds based on LDH (ternary layered double hydroxide) are considered the perfect supercapacitor electrode materials on account of their superior electrochemical qualities and distinct structural characteristics, and flexible supercapacitors are an ideal option as an energy source for wearable electronics. However, the prevalent aggregation effect of LDH materials results in significantly compromised actual specific capacitance, which limits its broad practical applications. In this research, a 3D eggshell-like interconnected porous carbon (IPC) framework with confinement and isolation capability is designed and synthesized by using glucose as the carbon source to disperse the LDH active material and enhance the conductivity of the composite material. Second, by constructing NiCoMn-LDH nanocage structure based on ZIF-67 (zeolitic imidazolate framework-67) at the nanometer scale the obtained IPC/NiCoMn-LDH electrode material can expose more active sites, which allows to achieve excellent specific capacitance (2236 F g -1 / 310.6 mAh g -1 at 1 A g -1 ), good rate as well as the desired cycle stability (85.9% of the initial capacitance upon 5000 cycles test). The constructed IPC/NiCoMn-LDH//IPC ASC (asymmetric supercapacitor) exhibits superior capacitive property (135 F g -1 /60.1 mAh g -1 at 0.5 A g -1 ) as well as desired energy density (40 Wh kg -1 at 800 W kg -1 )., (© 2023 Wiley‐VCH GmbH.)

Real-time telemedicine detection can solve the problem of the shortage of public medical resources caused by the coming aging society. However, the development of such an integrated monitoring system is hampered by the need for high-performance sensors and the strict-requirement of long-distance signal transmission and reproduction. Here, a bionic crack-spring fiber sensor (CSFS) inspired by spider leg and cirrus whiskers for stretchable and weavable electronics is reported. Trans-scale conductive percolation networks of multilayer graphene around the surface of outer spring-like Polyethylene terephthalate (PET) fibers and printing Ag enable a high sensitivity of 28475.6 and broad sensing range over 250%. The electromechanical changes in different stretching stages are simulated by Comsol to explain the response mechanism. The CSFS is incorporated into the fabric and realized the human-machine interactions (HMIs) for robot control. Furthermore, the 5G Narrowband Internet of Things (NB-IoT) system is developed for human healthcare data collection, transmission, and reproduction together with the integration of the CSFS, illustrating the huge potential of the approach in human-machine communication interfaces and intelligent telemedicine rehabilitation and diagnosis monitoring., (© 2024 The Authors. Advanced Science published by Wiley‐VCH GmbH.)

Clever and rational design of structural hierarchy, along with precise component adjustment, holds profound significance for the construction of high-performance supercapacitor electrode materials. In this study, a binder-free self-supported CCO@N 0.5 C 0.5 OH/NF cathode material is constructed with hierarchical hetero-core-shell honeycomb nanostructure by first growing CuCo 2 O 4 (CCO) nanopin arrays uniformly on highly conductive nickel foam (NF) substrate, and then anchoring Ni 0.5 Co 0.5 (OH) 2 (N 0.5 C 0.5 OH) bimetallic hydroxide nanosheet arrays on the CCO nanopin arrays by adjusting the molar ratio of Ni(OH) 2 and Co(OH) 2 . The constructed CCO@N 0.5 C 0.5 OH/NF electrode material showcases a wealth of multivalent metal ions and mesopores, along with good electrical conductivity, excellent electrochemical reaction rates, and robust long-term performance (capacitance retention rate of 87.2%). The CCO@N 0.5 C 0.5 OH/NF electrode, benefiting from the hierarchical structure of the material and the exceptional synergy between multiple components, demonstrates an excellent specific capacitance (2553.6 F g -1 at 1 A g -1 ). Furthermore, the assembled asymmetric CCO@N 0.5 C 0.5 OH/NF//AC/NF supercapacitor demonstrates a high energy density (70.1 Wh kg -1 at 850 W kg -1 ), and maintains robust capacitance cycling stability performance (83.7%) after undergoing 10 000 successive charges and discharges. It is noteworthy that the assembled supercapacitor exhibits an operating voltage (1.7 V) that is well above the theoretical value (1.5 V)., (© 2023 Wiley-VCH GmbH.)

Flexible energy storage device is one of the most critical components as power source for wearable electronics. The emergence of MXenes, a growing family of 2D nanomaterials, has demonstrated a brand-new possibility for flexible energy storage. However, the fabrication of MXene films with satisfactory mechanical, electrical, and electrochemical reliabilities remains challenging due to the weak interlayer interactions and self-restacking of MXene sheets. Sequential bridging of polydopamine/polyethyleneimine-functionalized (PDA/PEI)-coated MXene sheets to induce synergistically covalent and hydrogen binding connections of MXene-based films is demonstrated here. By interrupting self-hydrogen bonding and π-π stacking interactions, the introduction of long-chain PEI can not only inhibit the massive aggregation of PDA, but also improve the continuity of the interconnection network of PDA/PEI between MXene layers. Hence, the as-prepared MXene/PDA/PEI composite film displays high mechanical strength (≈366 MPa) which achieves 12-fold improvement compared with pure MXene film, as well as superior energy storage capability (≈454 F g -1  at 5 mV s -1 ) and rate performance of ≈48% at 10 000 mV s -1 . This modulation of inserted polymer between MXene layers can provide an avenue for assembling high performance MXene films, and can even be extended to the fabrication of other 2D platelets for varied applications., (© 2023 Wiley-VCH GmbH.)

The ambient electrochemical N 2 reduction reaction (NRR) is a future approach for the artificial NH 3 synthesis to overcome the problems of high-energy consumption and environmental pollution by Haber-Bosch technology. However, the challenge of N 2 activation on a catalyst surface and the competitive hydrogen evolution reaction make the current NRR unsatisfied. Herein, this work demonstrates that NbB 2 nanoflakes (NFs) exhibit excellent selectivity and durability in NRR, which produces NH 3 with a production rate of 30.5 µg h -1 mg cat -1 and a super-high Faraday efficiency (FE) of 40.2%. The high-selective NH 3 production is attributed to the large amount of active B vacancies on the surface of NbB 2 NFs. Density functional theory calculations suggest that the multiple atomic adsorption of N 2 on both unsaturated Nb and B atoms results in a significantly stretched N 2 molecule. The weakened NN triple bonds are easier to be broken for a biased NH 3 production. The diatomic catalysis is a future approach for NRR as it shows a special N 2 adsorption mode that can be well engineered., (© 2023 Wiley-VCH GmbH.)

Herein, the fabrication of reduced graphene oxide (RGO)-templated polymer composites for chemical removal of gaseous formaldehyde under ambient conditions is presented. The chemical removal of formaldehyde is achieved by a nucleophilic addition reaction between formaldehyde and aminooxy groups on the polymer chain ends to form the oxime bonds with the only byproduct of H 2 O. RGO is essential since it not only has an ultralarge surface area but also can act as a perfect template for immobilizing pyrene-terminated and aminooxy-functionalized polymers via strong π-π stacking interactions, while melamine foam provides a three-dimensional skeleton for loading RGO/polymer composites to afford a porous 3D structure for efficient formaldehyde removal. Since the oxime bond can be cleaved into aminooxy group in acidic media, the RGO/polymer composite can be regenerated for repeatable usage, which shows an excellent performance of adsorbing 14 mg of formaldehyde by 100 mg of the polymer at ambient condition., (© 2022 Wiley-VCH GmbH.)

Combining the self-sacrifice of a highly crystalline substance to design a multistep chain reaction towards ultrathin active-layer construction for high-performance water splitting with atmospheric-temperature conditions and an environmentally benign aqueous environment is extremely intriguing and full of challenges. Here, taking cobalt carbonate hydroxides (CCHs) as the initial crystalline material, we choose the Lewis acid metal salt of Fe(NO 3 ) 3 to induce an aqueous-phase chain reaction generating free CO 3 2- ions with subsequent instant FeCO 3 hydrolysis. The resultant ultrathin (∼5 nm) amorphous Fe-based hydroxide layer on CCH results in considerable activity in catalyzing the oxygen evolution reaction (OER) and hydrogen evolution reaction (HER), yielding 10/50 mA ⋅ cm -2 at overpotentials of 230/266.5 mV for OER and 72.5/197.5 mV for HER. The catalysts can operate constantly in 1.0 M KOH over 48 and 45 h for the OER and HER, respectively. For bifunctional catalysis for alkaline electrolyzer assembly, a cell voltage as low as 1.53 V was necessary to yield 10 mA cm -2 (1.7 V at 50 mA cm -2 ). This work rationally builds high-efficiency electrochemical bifunctional water-splitting catalysts and offers a trial in establishing a controllable nanolevel ultrathin lattice disorder layer through an atmospheric-temperature chemical route., (© 2022 Wiley-VCH GmbH.)

Piezoelectric arterial pulse wave dynamics are traditionally considered to be similar to those of typical blood pressure waves. However, achieving accurate continuous blood pressure wave monitoring based on arterial pulse waves remains challenging, because the correlation between piezoelectric pulse waves and their related blood pressure waves is unclear. To address this, the correlation between piezoelectric pulse waves and blood pressure waves is first elucidated via theoretical, simulation, and experimental analysis of these dynamics. Based on this correlation, the authors develop a wireless wearable continuous blood pressure monitoring system, with better portability than conventional systems that are based on the pulse wave velocity between multiple sensors. They explore the feasibility of achieving wearable continuous blood pressure monitoring without motion artifacts, using a single piezoelectric sensor. These findings eliminate the controversy over the arterial pulse wave piezoelectric response, and can potentially be used to develop a portable wearable continuous blood pressure monitoring device for the early prevention and daily control of hypertension., (© 2022 Wiley-VCH GmbH.)

The excellent electrical conductivity of graphene is due to its highly-conjugated structures. Manipulation of the electronic and mechanical properties of graphene can be achieved by controlling the destruction of its in-sheet conjugation system. Herein, we report the preparation of CoCeS x -SA@BPMW@RGO through π-π stacking interactions at the molecular level. In this study, sodium alginate was reacted with Co 2+ and Ce 3+ , and the composite was loaded onto a graphene surface. The graphene sheets were prepared using a bi-pyrene terminated molecular wire (BPMW) to avoid re-stacking of the grapheme sheets, thereby forming nanoscale spaces between sheets. The angle between the BPMW coplanar pyrene group and the phenyl group was 33.2°, and the graphene layer is supported in an oblique direction. Finally, a three-dimensional porous composite was obtained after annealing and vulcanization. The obtained CoCeS x -SA@BPMW@RGO exhibited excellent electrical conductivity and remarkable cycle stability. When the current density was 1 A g -1 , its specific capacitance was as high as 1004 F g -1 . BPMW modifies graphene through the synergistic effect of π-π stacking interaction and special structure to obtain excellent electrochemical performance. Moreover, a solid-state asymmetric supercapacitor device was fabricated based on the synthesized CoCeS x -SA@BPMW@RGO hybrid, which exhibited a power density of 979 W kg -1 at an energy density of 23.96 Wh kg -1 ., (© 2021 Wiley-VCH GmbH.)

From typical electrical appliances to thriving intelligent robots, the exchange of information between humans and machines has mainly relied on the contact sensor medium. However, this kind of contact interaction can cause severe problems, such as inevitable mechanical wear and cross-infection of bacteria or viruses between the users, especially during the COVID-19 pandemic. Therefore, revolutionary noncontact human-machine interaction (HMI) is highly desired in remote online detection and noncontact control systems. In this study, a flexible high-sensitivity humidity sensor and array are presented, fabricated by anchoring multilayer graphene (MG) into electrospun polyamide (PA) 66. The sensor works in noncontact mode for asthma detection, via monitoring the respiration rate in real time, and remote alarm systems and provides touchless interfaces in medicine delivery for bedridden patients. The physical structure of the large specific surface area and the chemical structure of the abundant water-absorbing functional groups of the PA66 nanofiber networks contribute to the high performance synergistically. This work can lead to a new era of noncontact HMI without the risk of contagiousness and provide a general and effective strategy for the development of smart electronics that require noncontact interaction., (© 2021 Wiley-VCH GmbH.)

Interface engineering has proven an effective strategy for designing high-performance water-oxidation catalysts. Interface construction combining the respective advantages of amorphous and crystalline phases, especially embedding amorphous phases in crystalline lattices, has been the focus of intensive research. This study concerns the construction of an amorphous-crystalline FeOOH phase boundary (a-c-FeOOH) by structural evolution of iron oxyhydroxide-isolated Fe(OH) 3 precursors from one-step hydrothermal synthesis. a-c-FeOOH demonstrates superb electrocatalytic activity for the oxygen evolution reaction (OER) with overpotential of 330 mV to drive a current density of 300 mA cm -2 in 1.0 m KOH, which is among the best OER catalysts and much better than the pristine amorphous or crystalline FeOOH alone. Density functional theory calculations reveal that the high-density a-c phase boundaries play a critical role in determining high OER activity., (© 2020 Wiley-VCH GmbH.)

Electrochemical water splitting is a clean and sustainable process for hydrogen production on a large scale as the electrical power required can be obtained from various renewable energy resources. The key challenge in electrochemical water splitting process is to develop low-cost electrocatalysts with high catalytic activity for the hydrogen evolution reaction (HER) on the cathode and the oxygen evolution reaction (OER) on the anode. OER is the most important half-reaction involved in water splitting, which has been extensively studied since the last century and a large amount of electrocatalysts including noble and non-noble metal-based materials have been developed. Among them, transition metal borides and borates (TMBs)-based compounds with various structures have attracted increasing attention owing to their excellent OER performance. In recent years, many efforts have been devoted to exploring the OER mechanism of TMBs and to improving the OER activity and stability of TMBs. In this review, recent research progress made in TMBs as efficient electrocatalysts for OER is summarized. The chemical properties, synthetic methodologies, catalytic performance evaluation, and improvement strategy of TMBs as OER electrocatalysts are discussed. The electrochemistry fundamentals of OER are first introduced in brief, followed by a summary of the preparation and performance of TMBs-based OER electrocatalysts. Finally, current challenges and future directions for TMBs-based OER electrocatalysts are discussed., (© 2020 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Free-standing films that display high strength and high electrical conductivity are critical for flexible electronics, such as electromagnetic interference (EMI) shielding coatings and current collectors for batteries and supercapacitors. 2D Ti 3 C 2 T x flakes are ideal candidates for making conductive films due to their high strength and metallic conductivity. It is, however, challenging to transfer those outstanding properties of single MXene flakes to macroscale films as a result of the small flake size and relatively poor flake alignment that occurs during solution-based processing. Here, a scalable method is shown for the fabrication of strong and highly conducting pure MXene films containing highly aligned large MXene flakes. These films demonstrate record tensile strength up to ≈570 MPa for a 940 nm thick film and electrical conductivity of ≈15 100 S cm -1 for a 214 nm thick film, which are both the highest values compared to previously reported pure Ti 3 C 2 T x films. These films also exhibit outstanding EMI shielding performance (≈50 dB for a 940 nm thick film) that exceeds other synthetic materials with comparable thickness. MXene films with aligned flakes provide an effective route for producing large-area, high-strength, and high-electrical-conductivity MXene-based films for future electronic applications., (© 2020 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Novel nanomaterials and advanced nanotechnology continuously push forward the rapid development of sustainable energy conversion and storage equipment. An emerging family of two-dimensional transition-metal carbides, nitrides and carbonitrides, also known as MXenes, have attracted increasing attention and in depth investigation. Benefitting from their unique intrinsic properties, MXenes have attracted significant attention and they have been considered as promising candidate materials for the development of environmentally friendly energy resources. A large number of studies show that MXenes have great potential in energy conversion and storage fields. Despite of their exceptional properties, MXenes also have some inherent characteristics, such as low capacities and unstable retention performances, which severely hinder their prospect applications in energy conversion and storage fields. In this Minireview, the latest progress on MXenes and their hybrid composites with small molecules, polymers, carbon or metal ions, and their applications in energy conversion and storage fields is highlighted, including their use in different types of batteries, supercapacitors, hydrogen/oxygen evolution reactions, electromagnetic interference absorption/shielding and solar steam generation. In addition, the critical challenges and further development prospects of MXene-based materials are also introduced., (© 2020 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Supercapacitors have attracted tremendous research interest, since they are expected to achieve battery-level energy density, while having a long calendar life and short charging time. Herein, a novel asymmetric supercapacitor has been successfully assembled from NiCo 2 S 4 nanosheets and spinous Fe 2 O 3 nanowire modified hollow melamine foam decorated with polypyrrole as positive and negative electrodes, respectively. Owing to the well-designed nanostructure and suitable matching of electrode materials, the assembled asymmetric supercapacitor (ASC) exhibits an extended operation voltage window of 1.6 V with an energy density of 20.1 Wh kg -1 at a power density of 159.4 kW kg -1 . Moreover, the ASC shows stable cycling stability, with 81.3 % retention after 4000 cycles and a low internal resistance of 1.03 Ω. Additionally, a 2.5 V light-emitting diode indicator can be lit up by three ASCs connected in series; this provides evidence of the practical application potential of the assembled energy-storage system. The excellent electrochemical performances should be credited to the significant enhancement of the specific surface area, charge transport, and mechanical stability resulting from the unique 3D morphology., (© 2020 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Conventional pressure sensing devices are well developed for either indirect evaluation or internal measuring of fluid pressure over millimeter scale. Whereas, specialized pressure sensors that can directly work in various liquid environments at micrometer scale remain challenging and rarely explored, but are of great importance in many biomedical applications. Here, pressure sensor technology that utilizes capillary action to self-assemble the pressure-sensitive element is introduced. Sophisticated control of capillary flow, tunable sensitivity to liquid pressure in various mediums, and multiple transduction modes are realized in a polymer device, which is also flexible (thickness of 8 µm), ultraminiature (effective volume of 18 × 100 × 580 µm 3 ), and transparent, enabling the sensor to work in some extreme situations, such as in narrow inner spaces (e.g., a microchannel of 220 µm in width and 100 µm in height), or on the surface of small objects (e.g., a 380 µm diameter needle). Potential applications of this sensor include disposables for in vivo and short-term measurements., (© 2019 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Snowflake-like MnO 2 @NiCo 2 O 4 composites were successfully fabricated by employing crossed snowflake-like MnO 2 nanorods as cores and one-dimensional (1D) NiCo 2 O 4 nanoneedles as shells. Impressively, the MnO 2 @NiCo 2 O 4 composites exhibited a highly efficient electromagnetic wave (EMW) absorbing capability, and the minimum reflection loss (RL) value reached -58.4 dB at 6.8 GHz for a thickness of 4.0 mm. The reasons for the improved EMW absorption capability of snowflake-like MnO 2 @NiCo 2 O 4 composites were analyzed. The unique core-shell structure, good impedance matching, and high dielectric loss were all found to be important contributors. Moreover, the interfacial polarization mainly stemmed from the heterostructure, a microcurrent generated from the 1D MnO 2 nanorods and NiCo 2 O 4 nanoneedles under alternating electromagnetic fields, and the synergistic effect from the different components were all beneficial to improve the EMW absorption performance. These results demonstrated that snowflake-like MnO 2 @NiCo 2 O 4 composites could be utilized as promising materials for practical EMW absorbing applications., (© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

MXenes are a new family of 2 D transition metal carbides and nitrides, which have attracted enormous attention in electrochemical energy storage, sensing technology, and catalysis owing to their good conductivity, high specific surface area, and excellent electrochemical properties. In this work, a series of Co 3 O 4 -doped 3 D MXene/RGO hybrid porous aerogels is designed and prepared through a facile in situ reduction and thermal annealing process, in which the reduced graphene oxide (RGO) conductive network can electrically link the separated Co 3 O 4 -MXene composite nanosheets, leading to enhanced electronic conductivity. It is found that upon using the Co 3 O 4 -MXene/RGO hybrid porous aerogel prepared with a mass ratio of Co 3 O 4 -MXene/RGO of 3:1 (CMR31) as an electrode for a supercapacitor, a superior specific capacitance of 345 F g -1 at the current density of 1 A g -1 is achieved, which is significantly higher than those of Ti 3 C 2 T x MXene, RGO, and MXene/RGO electrodes. In addition, a high capacitance retention (85 % of the initial capacitance after 10 000 cycles at a high current density of 3 A g -1 ) and a low internal resistance R s (0.44 Ω) can be achieved. An all-solid-state asymmetric supercapacitor (ASC) device is assembled using CMR31, and it has the ability to light up a blue LED indicator for 5 min if four ASCs are connected in series. Therefore, these novel Co 3 O 4 -MXene/RGO hybrid porous aerogels have potential practical applications in high-energy storage devices., (© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Fiber-shaped supercapacitors (FSCs) are promising energy storage solutions for powering miniaturized or wearable electronics. However, the scalable fabrication of fiber electrodes with high electrical conductivity and excellent energy storage performance for use in FSCs remains a challenge. Here, an easily scalable one-step wet-spinning approach is reported to fabricate highly conductive fibers using hybrid formulations of Ti 3 C 2 T x MXene nanosheets and poly(3,4-ethylenedioxythiophene):polystyrene sulfonate. This approach produces fibers with a record conductivity of ≈1489 S cm -1 , which is about five times higher than other reported Ti 3 C 2 T x MXene-based fibers (up to ≈290 S cm -1 ). The hybrid fiber at ≈70 wt% MXene shows a high volumetric capacitance (≈614.5 F cm -3 at 5 mV s -1 ) and an excellent rate performance (≈375.2 F cm -3 at 1000 mV s -1 ). When assembled into a free-standing FSC, the energy and power densities of the device reach ≈7.13 Wh cm -3 and ≈8249 mW cm -3 , respectively. The excellent strength and flexibility of the hybrid fibers allow them to be wrapped on a silicone elastomer fiber to achieve an elastic FSC with 96% capacitance retention when cyclically stretched to 100% strain. This work demonstrates the potential of MXene-based fiber electrodes and their scalable production for fiber-based energy storage applications., (© 2019 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

In this review, we focus on recent advances in the synthesis of polymer-functionalized transition-metal-based nanomaterials and follow this up by discussing their applications in bioimaging diagnosis and cancer therapy. Transition-metal-based nanomaterials show great potential in cancer therapy owing to their intensive near-IR absorption, excellent photothermal conversion efficiency, strong X-ray attenuation, and magnetic properties. Functional polymers are usually introduced by a one-step or multistep method to further endow these nanomaterials with great biocompatibility and physiological stability. Polymer-decorated transition-metal nanomaterials show great potential in multimodal imaging diagnosis (photoacoustic imaging, computed tomography, photoluminescence imaging, positron emission tomography, etc.) and cancer therapy (chemotherapy, photothermal therapy, microwave therapy, radiotherapy, photodynamic therapy). At the end of this review, the prospects of these polymer-decorated transition-metal-based nanomaterials are also discussed., (© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Novel nanomaterials and advanced nanotechnologies continue to promote the fast development of new approaches for efficient tumor therapy. As an alternative choice to various traditional therapies, non-invasive photothermal therapy (PTT) has attracted significant attention mainly due to its low cost, highly localizing, specific tumor treatment and minimal side effects on healthy tissues. PTT induced by photo-absorbing agents which can absorb and convert the external NIR laser into heat to ablate tumors. Plenty of studies have shown the significant potential of PTT to treat tumors in future practical applications. However, PTT alone usually could not eradicate tumors considering the intensity of laser gradual attenuates in biological tissues and the heat generated tends to distribute inhomogeneous within tumors tissues. Combination of chemotherapy with photothermal therapy into one system for tumor therapy is an effective strategy to further improve the therapy efficiency. In this Minireview, we focus on the recent advances in constructing PTT therapeutic and multi-model combination therapeutic via integrating nanomaterials and functional polymers., (© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Concavo-convex micelles with controllable sizes and nanostructures are prepared via self-assembling polymer-enzyme (e.g., shellac enzyme) conjugates with heterogeneous polymer chains, which exhibit higher enzyme stability (300%) and bioactivity (760%) comparing with the well-defined ones. The applied amphiphilic and negatively charged copolymer, poly (methyl methacrylate)-block-poly (sodium p-styrene sulfonate), is synthesized via reversible addition-fragmentation chain transfer polymerization to modify shellac enzyme and immobilize the enzyme bioactivity inducer by covalent conjugation and electrostatic attraction, respectively. The degradation test of catechol confirms the application potential of as-prepared micelles as an efficient and economical decontaminant., (© 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Molybdenum disulfide (MoS 2 ) nanosheets have attracted significant attention due to their photothermal properties, but the poor solubility and colloidal stability limited their further application in biomedical field. Here, we report a targeted photothermal controllable nanocarrier consisting of MoS 2 nanosheets modified with block copolymer P(OEG-A)-b-P(VBA-co-KH570) and targeting ligand transferrin. P(OEG-A)-b-P(VBA-co-KH570) is synthesized by RAFT polymerization and utilized not only to improve the solubility of MoS 2 nanosheets but also efficiently load the anti-cancer drug doxorubicin (DOX) through an acid-cleavable Schiff base linker. Thiol-functionalized transferrin (Tf-SH) is anchored onto the surface of MoS 2 nanosheets by the formation of disulfide bonds, which could further enhance the cellular uptake of DOX and MoS 2 to HepG2 cells for high-efficiency synergetic therapy. The drug release experiments exhibited the minimal release of DOX at room temperature and neutral pH, and the maximal drug release of 53 % at acidic tumor pH and hyperthermia condition after 48 h. In addition, the DOX-loaded, Tf-SH and P(OEG-A)-b-P(VBA-co-KH570) modified MoS 2 (DOX-POVK-MoS 2 -Tf) showed better a therapeutic effect than DOX-POVK-MoS 2 and POVK-MoS 2 , probably owing to the combined effects of target-directed uptake, acid-triggered drug release, and NIR induced localized heating, which suggest the designed MoS 2 nanocarriers are promising for applications in multi-modal cancer therapy., (© 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Developing earth-abundant electrocatalysts for efficient and stable water oxidation under near neutral conditions is of great importance but still remains a key challenge. Herein, we demonstrate the development of an interconnected network of core-shell CoP@CoBiPi through anodic polarization of a CoP nanoarray in potassium borate aqueous electrolyte (KBi). This 3 D CoP@CoBiPi exhibits high catalytic activity for water oxidation at pH 9.2 and needs an overpotential (η) of only 410 mV to drive a geometrical catalytic current density of 10 mA cm -2 , with a high turnover frequency of 819 h -1 at an overpotential of 610 mV. Remarkably, this catalyst also demonstrates high long-term electrochemical stability with its activity being maintained for at least 27 h in KBi. This study provides us an attractive earth-abundant 3 D catalyst electrode for water-splitting devices toward efficient and stable water oxidation under benign conditions., (© 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Tungsten oxide (WO 3- x ), a new alternative to conventional semiconductor material, has attracted numerous attentions owning to its widespread potential applications. Various methods have been reported for the synthesis of WO 3- x nanostructures such as nanowires or nanodots. However, templates or surfactants are often required for the synthesis, which significantly complicate the process and hinder the broad applications. Herein, one-pot template/surfactant-free solvothermal method is proposed to synthesize the WO 3- x nanostructures including fluorescent quantum dots (QDs) and bundle-like nanowires simultaneously. The as-prepared WO 3- x QDs can be well dispersed in aqueous medium, exhibit excellent photoluminescent properties, and show an average size of 3.25 ± 0.25 nm as evidenced by transmission electron microscopy. Meanwhile, the diameter of the WO 3- x nanowires is found to be about 27.5 nm as manifested by the scanning electron microscope images. The generation mechanism for these two WO 3- x nanostructures are systematically studied and proposed. The WO 3- x QDs have been successfully applied in efficient fluorescent staining and specific ferric ion detection. Moreover, the WO 3- x nanowires can be utilized as effective dielectric materials for electromagnetic wave absorption., (© 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

The controlled spatial organization or compartmentalization of multi-enzyme cascade reactions to transfer a substrate from one enzyme to another for substrate channeling on scaffolds has sparked increasing interest in recent years. Here, we use graphene oxides to study the dependence of the activity of cascade reactions in a closely packed, randomly immobilized enzyme system on a 2 D scaffold. We first observe that the hydrophobicity of graphene oxides and various enzyme architectures for co-immobilized systems are important attributes for achieving high product-conversion rates. A transient time close to 0 s can be achieved if enzymes are randomly immobilized close to one another, owing to direct molecular channeling. This contributes to overcoming complications regarding control of the spatial arrangement of the enzymes. Furthermore, a fabricated bienzyme paper can be used for glucose detection with high stability, reusability, and enhanced substrate channeling. Our findings provide new guidance for enzyme orientation on 2 D scaffolds, which may be extrapolated to other multienzyme cascade systems., (© 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

The determination of oxygenous groups, conjugated area ratio, and reduction efficiency of graphene oxide (GO) is a difficult task because of its heterogeneous structure. Herein, a novel approach is described for a detailed understanding of the surface chemistry of GO by using pyrene as a fluorescent probe through π-π stacking interactions., (© 2016 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Herein, a conceptually new and straightforward aqueous route is described for the synthesis of hydroxyl- and amino-functionalized boron nitride quantum dots (BNQDs) with quantum yields (QY) as high as 18.3 % by using a facile bottom-up approach, in which a mixture of boric acid and ammonia solution was hydrothermally treated in one pot at 200 °C for 12 h. The functionalized BNQDs, with excellent photoluminescence properties, could be easily dispersed in an aqueous medium and applied as fluorescent probes for the detection of ferrous (Fe 2+ ) and ferric (Fe 3+ ) ions with excellent selectivity and low detection limits. The mechanisms for the hydrothermal reaction and fluorescence quenching were also simulated by using density functional theory (DFT), which confirmed the feasibility and advantages of this strategy. It provides a scalable and eco-friendly method for preparation of BNQDs with good dispersability and could also be generalized to the synthesis of other 2D quantum dots and nanoplates., (© 2016 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

In this work, for the first time, a cobalt carbonate hydroxide (Co(CO 3 ) 0.5 (OH)⋅0.11 H 2 O) nanowire array on Ti mesh (CHNA/Ti) was applied to drive the dehydrogenation of alkaline NaBH 4 solution for on-demand hydrogen production. Compared with other nanostructured Co-based catalyst systems, CHNA/Ti can be activated more quickly and separated easily from fuel solutions. This self-supported cobalt salt nanowire array catalyst works as an efficient and robust 3D catalyst for the hydrolysis reaction of NaBH 4 with a hydrogen generation rate of 4000 mL min -1  g Co -1 and a low apparent activation energy of 39.78 kJ mol -1 and offers an attractive system for on-demand hydrogen generation., (© 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Graphene has been regarded as a promising candidate for a new generation of transparent electrodes (TEs) due to its prominent characteristics including high optical transmittance, exceptional electronic transport, outstanding mechanical strength, and environmental stability. Comprehensive and critical insights into the latest advances in graphene-based TEs (GTEs) since, but not limited to 2013, are provided, with an emphasis on fabrication, modification, and versatile applications. Several emerging application areas not previously summarized, including electrochromic devices, supercapacitors, electrochemical and electrochemiluminescent sensors, are discussed in detail. The challenges and prospects in these fields are also addressed., (© 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

The preparation of thermoresponsive drug carriers with a self-destruction property is presented. These drug carriers were fabricated by incorporation of drug molecules and thermoresponsive copolymer, poly(N-isopropylacrylamide-co-acrylamide), into silica nanoparticles in a one-pot preparation process. The enhanced drug release was primarily attributed to faster molecule diffusion resulting from the particle decomposition triggered by phase transformation of the copolymer upon the temperature change. The decomposition of the drug carriers into small fragments should benefit their fast excretion from the body. In addition, the resulting drug-loaded nanoparticles showed faster drug release in an acidic environment (pH 5) than in a neutral one. The controlled drug release of methylene blue and doxorubicin hydrochloride and the self-decomposition of the drug carriers were successfully characterized by using TEM, UV/Vis spectroscopy, and confocal microscopy. Together with the nontoxicity and excellent biocompatibility of the copolymer/SiO2 composite, the features of controlled drug release and simultaneous carrier self-destruction provided a promising opportunity for designing various novel drug-delivery systems., (© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)