Over the past decade, structural DNA nanotechnology has been well developed to be a promising and powerful technique to generate various nanostructures with programmability, spatial organization and biocompatibility. With the advent of computer-aided tools, framework nucleic acids have been employed in a series of biomedical applications, ranging from biosensing, bioimaging, diagnosis, to therapeutics. In this review, we summarized recent advances in the construction of precisely assembled DNA nanostructures, and DNA-engineered biomimetics. We also outlined the challenges and opportunities for the translational applications of framework nucleic acids.

With the increased energy demand, developing renewable and clean energy technologies becomes more and more significant to mitigate climate warming and alleviate the environmental pollution. The key point is design and synthesis of low cost and efficient materials for a wide variety of electrochemical reactions. Over the past ten years, two-dimensional(2D) nanomaterials that graphene represents have been paid much attention as a class of the most promising candidates for heterogeneous electrocatalysts in electrochemical storage and conversion. Their unique properties, such as good chemical stability, good flexibility, and good electronic properties, along with their nano-sized thickness and large specific area, make them exhibit comprehensively good performances for energy storage and conversion. Here, we present an overview on the recent advances in electrochemical applications of graphene, graphdiyne, transition metal dichalcogenides(TMDs), and MXenes for supercapacitors(SCs), oxygen reduction reaction (ORR), and hydrogen evolution reaction(HER).

The pressing demand for high-energy/power lithium-ion batteries requires the deployment of cathode materials with higher capacity and output voltage. Despite more than ten years of research, high-voltage cathode materials, such as high-voltage layered oxides, spinel LiNi_0.5Mn_1.5O₄, and high-voltage polyanionic compounds still cannot be commercially viable due to the instabilities of standard electrolytes, cathode materials, and cathode electrolyte interphases under high-voltage operation. This paper summarizes the recent advances in addressing the surface and interface issues haunting the application of high-voltage cathode materials. The understanding of the limitations and advantages of different modification protocols will direct the future endeavours on advancing high-energy/power lithium-ion batteries.

Atmospheric water harvesting based on vapor adsorption is a newly emerged and potential technology to supply portable water for arid areas. To efficiently harvest vapor from the air, sorbents are required to have considerable adsorption capacity, easy regeneration and high stability. With the advantages of porous structure, tunable pore size and tailorable hydrophilicity, metal-organic frameworks (MOFs) have demonstrated excellent performance in vapor adsorption and water generation. In this review, we first discuss the degradation mechanisms of MOFs exposed to water and summarize the structure-stability relationship; by centering on the adsorption isotherms, the connection between the structure of MOFs and the water adsorption property is illuminated; finally, some prospects are suggested in order to push forward the progress of this technology.

Polymeric devices are the workhorses of modern technologies. As one of the cutting-edge technology leveraging polymeric materials, nanogenerator that could convert micro-/nano-scale mechanical energy into electricity based on the mechanism of piezoelectricity and triboelectricity exhibited great promise for biomedical applications, owning to the simple configuration, high efficiency, decent electrical output, biomimetic property as well as excellent biocompatibility. In this manuscript, the recent representative developments of NGs in biomedical applications are reviewed. Fundamentals, such as working mechanisms underneath different NG prototypes are discussed, which is followed by innovative strategies endowing NG with biomimetic mechanical properties. Intriguing attempts to implement NG in specific biomedical fields(e.g., power source for implantable medical devices, therapeutic electric stimulator, etc.) are introduced and analyzed. This manuscript ends up with subsection summarizing existed challenges while providing potential solutions for future NG developments in biomedical engineering.

Energy storage will witness a leap of understanding of new battery chemistries. Considering the safety that cannot be compromised, new aqueous batteries may surface as the solutions to meet the immense market needs, where the growth of renewables is no longer limited by the lack of storage. Aqueous Zn-metal batteries are intriguing candidates to deliver the desirable properties and exhibit competitive levelized energy cost. However, the fact that most commercial Zn batteries are primary batteries states the difficulty of reversibility for the reactions of electrodes in such batteries. This article will highlight the practical needs that guide the development of storage batteries. The causes of irreversibility for both cathode and zinc metal anode are discussed, and the potential solutions for these challenges are summarized. Zn metal batteries may one day address the storage needs, and there exists a vast potential to further improve the properties of reactions in this battery.

Planarized intramolecular charge transfer(PLICT) state can facilitate the fluorescence process thanks to the relative excellent planarity. Recently, we have discovered that the excited state quinone-conformation induced planarization(ESQIP) occurring on tetraphenylpyrazine(TPP) based derivatives could furnish them with PLICT feature. Unlike to the well-known intramolecular charge transfer, strengthening the electron-donating nature on the donor(D) moiety did not impair the PLICT. The calculation results showed that planarization of the TPP based compounds scarcely accompanied with energy wastage while amount of energy was required for the torsion on geometries. In the polar solvents, the energy consumption for planarization could further decrease, but that for twisting structure would increase. To take advantage of the transformation of the frontier orbitals’ distribution, the PLICT type materials would perform a potential application on organic light-emitting diodes(OLEDs).

Hollow multishelled structures(HoMSs) Co₃O₄ with specially appointed shell number(double-, triple- and quadruple-) were accurately prepared by a sequential templating approach. Due to the superiorities of inimitable porous multishelled structure, triple-HoMSs Co₃O₄ achieved the best performance among all the samples with a specific capacitance of 1028.9 F/g at 10 mV/s and 688.2 F/g at 0.5 A/g, respectively. Furthermore, the electrode delivered a high rate performance(89.8% retention at 10 A/g) and excellent cycle stability(6.8% loss over 2000 cycles), showing a great promise for practical application in the future.

By employing an electron-rich tricarboxytriphenyl amine as donor ligand and electron-deficient 2,4,6-tris(pyridin-4-yl)-1,3,5-triazine as acceptor ligand to assemble with Zn²⁺ ions, three new coordination polymers were successfully synthesized and characterized systematically. Three compounds with different structures were obtained by regulating the reaction solvent, and the effect of the reaction solvent on the synthesis of crystals was explored. Furthermore, the photophysical properties of the compounds were investigated.

Self-assembled supramolecular networks are promising spacer layer for electronic decoupling from the metal substrate. However, the mechanism behind of how the intrinsic electronic structure of spacer layers affects the adsorbate is still unclear. Here a hydrogen bonded network composed of n-type semiconducting molecules 3,4,9,10-perylene-tetracarboxylic-dianhydride(PTCDA) is prepared under ultra-high vacuum to serve as a spacer layer for functional organics C₆₀ on Au(111). The geometric and electronic information of C₆₀ was investigated by scanning tunneling microscopy and scanning tunneling spectroscopy(STM/STS) at 5 K. Effective decoupling from the metal surface yields an energy gap of 3.67 eV for C₆₀ ^2nd, merely considering the HOMO-LUMO peak separation. The broadening of resonance peaks in STS measurements however indicates unneglected interlayer interactions in this hetero-organic system. Moreover, we scrutinize the nucleation sites of C₆₀ on PTCDA layer and attribute this to the decreased diffusion capability on a less dense molecular arrangement possessing inhomogeneous spatial distribution of unoccupied molecular orbitals.

Two new alkaline metal borates containing 1D {B₅}/{B₆} oxoboron helical chains, namely Na_0.5[B₅O₈(OH)₂]_0.5[B₅O₆(OH)₂]_0.5·0.5H₃O(1) and NaKCs[B₆O₉(OH) ₃](2) were synthesized under solvothermal conditions. Compound 1 contains the interesting alternative left- and right-handed helical {[B₅O₈(OH)₂][B₅O₆(OH)₂]}²⁻ ({B₅}-1 and {B₅}-2) 1D chains and compound 2 possesses the similar [B₆O₁₁(OH)₃]⁷⁻({B₆}) chains. Their 1D chains are further assembled into 2D layers and 3D supramolecular frameworks through O-H⋯O hydrogen bonds. In addition, the UV cutoff edge of compounds 1 and 2 is both below 190 nm.

Metal selenides as anode materials for sodium-ion batteries have attracted considerable attention owing to their high theoretical specific capacities and variable composition and structures. However, the achievement of long cycle life and superior rate performance is challenging for these selenide materials due to the volume variation upon cycling. Herein, a composite composed of a new binary-metal selenide[Cu₂SnSe₃(CSS)] and carbon nanotubes(CNTs) was constructed via a hydrothermal process followed by calcination at 600 °C. Benefited from the unique structure of binary-metal selenide and the conductive network of CNTs, the Cu₂SnSe₃/carbon nanotubes(CSS/CNT) composite exhibits excellent electrochemical performance when used as an anode material for sodium-ion batteries. A reversible specific capacity of 399 mA·h/g can be maintained at a current density of 100 mA/g even after 100 cycles. This work provides a promising strategy for rational design of binary-metal selenides upon delicate crystal phase control as electrode materials.

Flexible asymmetric supercapacitor is fabricated with three dimensional(3D) Fe₂O₃/Ni(OH)₂ composite brush anode and Ni(OH)₂/MoO₂ honeycomb cathode. Particularly for 3D composite brush anode, a layer of thin Fe₂O₃ film is firmly adhered on a 3D Ni brush current collector with the assist of Ni(OH)₂, functioning as both adherence layer and pseudocapacitive active material. The unique 3D Ni brush current collector possesses large surface area and stretching architecture, which facilitate to achieve the composite anode with high gravimetric capacitance of 2158 F/g. In terms of cathode, Ni(OH)₂ and MoO₂ have a synergistic effect to improve the specific capacitance, and the resulting Ni(OH)₂/MoO₂ honeycomb cathode shows a very high gravimetric capacitance up to 3264 F/g. The asymmetric supercapacitor(ASC) has balanced cathode and anode, and exhibits an ultrahigh gravimetric capacitance of 1427 F/g and an energy density of 476 Wh/kg. The energy density of ASC is 3–4 times higher than those of other reported aqueous electrolyte-based supercapacitors and even comparable to that of commercial lithium ion batteries. The device also shows marginal capacitance degradation after 1000 cycles’ bending test, demonstrating its potency in the application of flexible energy storage devices.

Developing high activity catalysts for hydrogen oxidation reaction(HOR) under alkaline condition remains a challenge in the exchange membrane fuel cell(AEMFC). Herein, we report that the activity of carbon-supported platinum(Pt/C) towards the hydrogen oxidation reaction(HOR) in alkaline media can be remarkably enhanced by simple immersion of Pt/C in nickel chloride solution. The adsorption of hydrogen on the catalyst surface is weakened by modification of nickel. The HOR activity on the Pt/C after immersion possesses an excellent mass current density of 33.4 A/g_metal, which is 18% higher than that(28.3 A/g_metal) on Pt/C.

Copper/oxalic diamide-promoted dimerization of tetrachlorinated perylene bisimide to construct highly-fused diperylene bisimides through Ullmann coupling and zipper-mode double C-H activation has been developed in this study. This one-step reaction combining homocoupling with C-H activation proceeded smoothly under the action of inexpensive metal-ligand system. This protocol is expected to expand the available synthetic tools for condensed ring systems of perylene bisimide(PBIs).

Recently, sodium-ion batteries gradually become the promising alternative to lithium-ion batteries because of cost considerations. In this work, a kind of Bi₂MoO₆ nanosheets@N,S codoped graphene composite is designed and fabricated for sodium storage applications. Detailed characterizations are employed to investigate its morphology, structure and chemical compositions. When evaluated as an anode material for sodium-ion batteries, the as-prepared composite is able to display a specific capacity of 254 mA·h/g after 50 cycles at a current density of 0.2 A/g, and 186 mA·h/g at 1.6 A/g during the rate capability test. As a result, the further morphology and structure optimization is still required for high performance sodium-ion batteries.

BiVO₄, a promising visible-light responding photocatalyst, has aroused extensive research interest because of inexpensiveness and excellent chemical stability. However, its main drawback is the poor photoinduced charge-transfer dynamics. Building nanostructures is an effective way to tackle this problem. Herein, we put forward a new method to prepare nanostructured BiVO₄ from Bi-based metal-organic frameworks[Bi-MOF(CAU-17)] precursor. The as-prepared material has a rod-like morphology inherited from the Bi-MOF sacrificial template and consists of small nanoparticle as building blocks. Compared with its counterparts prepared by conventional methods, MOF-derived nanostructured BiVO₄ shows better light absorption ability, narrower bandgap, and improved electrical conductivity as well as reduced recombination. Consequently, BiVO₄ nanostructure demonstrates high photocatalytic activity under visible light towards the degradation of methylene blue. Methylene blue can be degraded up to 90% within 30 min with a reaction rate constant of 0.058 min⁻¹. Moreover, the cycling stability of the catalyst is excellent to withstand unchanged degradation efficiency for at least 5 cycles.

Photocatalytic reduction of CO₂(CO₂PR) to valuable solar fuels is considered as a promising route to the amelioration of fossil fuel conundrum and the mitigation of greenhouse gases. Although progress has been made to enhance CO₂PR performance, the available method that can promote the selectivity of CO₂PR products remains to be a challenge. In this work, we synthesized NO₃ ⁻ or CO₃ ²⁻ intercalated NiAl-layered double hydroxide(NiAl-LDH) photocatalysts and investigated the performance of CO₂PR in the presence of an electron donor and a photosensitizer. Compared with Ni2Al-CO₃ ²⁻, Ni2Al-NO₃ ⁻ exhibited superior catalytic performance in the CO₂PR, and the resulted selectivity of CH₄ in Ni2Al-NO₃ ⁻(6.1%) was 12.2 times that of Ni2Al-CO₃ ²⁻(0.5%) under visible light irradiation. X-Ray absorption fine structure(XAFS) result reveals a relative abundance of defects in Ni2Al-NO₃ ⁻, which played as active sites and promoted charge transfer in CO₂PR for the efficient CH₄ evolution.

Protein delivery is of central importance for both diagnostic and therapeutic applications. However, protein delivery faces challenges including poor endosomal escape and thus limited efficiency. Here, we report the facile construction and screening of a small library of cationic helical polypeptides for cytosolic protein delivery. The library is based on a random copolymer poly(γ-{2-[2-(2-methoxyethoxy)ethoxy]ethoxy}esteryl-L-glutamate)-randompoly(γ-6-chlorohexyl-L-glutamate)[P(EG₃-r-ClC₆)Glu], which is then modified with various pyridine derivatives and alkyl thiols. Flow Cytometry, confocal laser scanning microscopy, and viability assay collaboratively identify two leading polymers, showing efficient delivery of enhanced green fluorescent protein(eGFP) and low cytotoxicity. This finding is further validated by the cytosolic delivery of RNase A and cytochrome C(Cyt C) to HeLa cells in the viability assay. Together, this work demonstrates that high-throughput screening is an effective and viable approach to the selection of cationic helical polypeptides for the cytosolic delivery of functional proteins.

In this study, the disposable facial tissues derived carbon aerogels(DFTs-CAs) were synthesized using disposable facial tissues as the raw material for fabricating a sensitive amperometric ascorbic acid(AA) sensor. The experimental results indicated that compared to glassy carbon electrode(GCE) and the popular carbon nanotubes modified GCE(CNTs/GCE), DFTs-CAs modified GCE(DFTs-CAs/GCE) exhibited better electrocatalytic activity(i.e., lower peak potential and higher peak current) for AA electrooxidation and higher analytical performance for AA determination(i.e., wider linear range, higher sensitivity and lower detection limit), which could be most likely due to the high density of defective sites and large specific surface area of DFTs-CAs. Especially, the DFTs-CAs/GCE was used for evaluating the AA level in real samples(i.e., medical injection dose, vitamin C tablets, fresh orange juice and human urine) and the results are satisfactory.

Break junction technique allows researchers to probe charge transport properties in a single Perovskite quantum dot(QD) with an Ångstrom scale resolution, and observe signatures of quantum interference effects at room temperature.

Prof. Zhai Tianyou and co-workers introduce the concept of 2D inorganic molecular crystals, which are different from traditional 2D atomic crystals, such as graphene, MoS₂, black phosphorus, MXene, etc. The materials system is unique, and completely new to the community. Another research boom on 2D molecular materials may thus be drawn in the scope of electronics, energy and environment. This work has been published online in the Nature Communications in October 17, 2019.

To achieve the stereoselective and regioselective diamination of alkenes, Xu et al. developed an electro-chemical protocol for the diamination of aryl alkenes with sulfamides by using triarylamine as a redox mediator. The chemistry proceeded in an undivided cell under constant current conditions, featuring not only wide scope of substrates and reasonable yields, but also excellent diastereoselectivity(>20:1 dr) and regioselectivity. This work has been published in the Nature Communications and can be reached at https://doi.org/10.1038/s41467-019-13024-5.