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Minimizing precious metal loading into electrocatalysts for water splitting is vital to promoting hydrogen energy technology toward practical applications. Low-content loading of precious-metal electrocatalysts is achieved by decorating precious metal nanostructures on co-electrocatalysts typically via surface confinement. Here, an electrocatalyst of ultralow-content Pt nanodots (0.71 wt%)/Ni 3 Fe nanoparticles on reduced oxidation graphene (Pt/Ni 3 Fe/rGO) is constructed for overall water splitting by pyrolyzing a single-source precursor PtCl 6 3- guest-intercalated MgNiFe-layered double hydroxide (MgNiFe-LDH) host via a distinctive interlayer confinement. Consequently, Pt/Ni 3 Fe/rGO demonstrates attractive overpotentials of 240 and 76 mV at 10 mA cm -2 for the oxygen and hydrogen evolution reactions (OER and HER), respectively, outperforming those of its /Ni 3 Fe/rGO counterpart. Moreover, the Pt/Ni 3 Fe/rGO∥Pt/Ni 3 Fe/rGO electrolyzer generates a current density of 10 mA cm -2 at 1.55 V, with a retention of 92.4% after 50 h. Furthermore, the measured specific activity and low transfer resistance, as well as the density functional theory (DFT) calculations, indicate that the active Pt/Ni 3 Fe in Pt/Ni 3 Fe/rGO can optimize the adsorption/desorption of reaction intermediates and thus boost OER/HER kinetics, all of which lead to enhanced performance. The results demonstrate that such an interlayer confinement-based synthesis strategy can allow for the design of cost-effective precious nanodots as potential electrocatalysts.

O3-type layered oxide cathodes (Na x TMO 2 ) for sodium-ion batteries (SIBs) have attracted significant attention as one of the most promising potential candidates for practical energy storage applications. The poor Na + diffusion kinetics is, however, one of the major obstacles to advancing large-scale practical application. Herein, we report bismuth-doped O3-NaNi 0.5 Mn 0.5 O 2 (NMB) microspheres consisting of unique primary nanoplatelets with the radially oriented {010} active lattice facets. The NMB combines the advantages of the oriented and exposed electrochemical active planes for direct paths of Na + diffusion, and the thick primary nanoplatelets for less surface parasitic reactions with the electrolyte. Consequently, the NMB cathode exhibits a long-term stability with an excellent capacity retention of 72.5% at 1 C after 300 cycles and an enhanced rate capability at a 0.1 C to 10 C rate (1 C = 240 mA g -1 ). Furthermore, the enhancement is elucidated by the small volume change, thin cathode-electrolyte-interphase (CEI) layer, and rapid Na + diffusion kinetics. In particular, the radial orientation-based Bi-doping strategy is demonstrated to be effective at boosting electrochemical performance in other layered oxides (such as Bi-doped NaNi 0.45 Mn 0.45 Ti 0.1 O 2 and NaNi 1/3 Fe 1/3 Mn 1/3 O 2 ). The results provide a promising strategy of utilizing the advantages of the oriented active facets of primary platelets and secondary particles to develop high-rate layered oxide cathodes for SIBs.

Environmentally friendly P2-type layered iron manganese oxides appear to be one of the most potential cathode materials for sodium-ion batteries (SIBs). However, their practical application is hindered by the unfavorable phase transitions, dissolution of transition metals, and poor air stability. One effective strategy by either single-cation doping or high-cost Li involved co-doping is used to alleviate the problems. Here, low-cost Cu/Ti co-doping is introduced to boost P2-Na 0.7 Cu 0.2 Fe 0.2 Mn 0.5 Ti 0.1 O 2 as an air and electrochemical stable cathode material for SIBs. The resulting electrode delivers an initial capacity of 130 mAh g -1 at 0.1C within 2.0-4.2 V, a reversible discharge capacity of 61.0 mAh g -1 at a high rate of 5C and a capacity retention ratio exceeding 71.1% after 300 cycles. In particular, the co-doped crystal structure is well-maintained after 1 month of exposure to air, and even 3 days of soaking in water. Furthermore, the enhancement is elucidated by the effectively mitigated P2-Z and the completely suppressed P2-P'2 phase transitions, the decreased volume variation proved by in-situ X-ray diffraction (XRD), as well as the lowered transition-metal dissolution evidenced by inductively coupled plasma optical emission spectrometer (ICP-OES) and X-ray photoelectron spectroscopy (XPS). The low-lost Cu/Ti doping strategy could thus be effective for designing and preparing environmentally friendly and high-performance cathode materials for SIBs., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Optimizing charge transfer and alleviating volume expansion in electrode materials are critical to maximize electrochemical performance for energy-storage systems. Herein, an atomically thin soft-rigid Co 9 S 8 @MoS 2 core-shell heterostructure with dual cation vacancies at the atomic interface is constructed as a promising anode for high-performance sodium-ion batteries. The dual cation vacancies involving V Co and V Mo in the heterostructure and the soft MoS 2 shell afford ionic pathways for rapid charge transfer, as well as the rigid Co 9 S 8 core acting as the dominant active component and resisting structural deformation during charge-discharge. Electrochemical testing and theoretical calculations demonstrate both excellent Na + -transfer kinetics and pseudocapacitive behavior. Consequently, the soft-rigid heterostructure delivers extraordinary sodium-storage performance (389.7 mA h g -1 after 500 cycles at 5.0 A g -1 ), superior to those of the single-phase counterparts: the assembled Na 3 V 2 (PO 4 ) 3 ||d-Co 9 S 8 @MoS 2 /S-Gr full cell achieves an energy density of 235.5 Wh kg -1 at 0.5 C. This finding opens up a unique strategy of soft-rigid heterostructure and broadens the horizons of material design in energy storage and conversion., (© 2023 Wiley-VCH GmbH.)

In this paper, highly dispersed hierarchical coral spheres of CeO 2 /ZnO have been constructed through a facile template-free hydrothermal strategy, followed by an annealing treatment. The resulting coral spheres exhibit enhanced activity for acetone sensing compared with CeO 2 or ZnO as well as excellent cyclability and long-term stability. At the optimum working temperature of 245 °C, by controlling the ratio of Ce/Zn, the highest response of the coral spheres towards 100 ppm acetone is up to 145, which is about 5.5 times that of ZnO coral spheres. The significantly improved gas sensing activity may be ascribed to the well-dispersed and assembled CeO 2 nanoparticles on the surface of ZnO coral spheres and the heterojunctions between CeO 2 and ZnO, which produced abundant oxygen vacancies in the CeO 2 /ZnO coral spheres.

The development of high-efficiency multi-component composite anode nanomaterials for sodium-ion batteries (SIBs) is critical for advancing the further practical application. Numerous multi-component nanomaterials are constructed typically via confinement strategies of surface templating or three-dimensional encapsulation. Herein, a composite of heterostructural multiple sulfides (MoS 2 /SnS/CoS) well-dispersed on graphene is prepared as an anode nanomaterial for SIBs, via a distinctive lattice confinement effect of a ternary CoMoSn-layered double-hydroxide (CoMoSn-LDH) precursor. Electrochemical testing demonstrates that the composite delivers a high-reversible capacity (627.6 mA h g -1 after 100 cycles at 0.1 A g -1 ) and high rate capacity of 304.9 mA h g -1 after 1000 cycles at 5.0 A g -1 , outperforming those of the counterparts of single-, bi- and mixed sulfides. Furthermore, the enhancement is elucidated experimentally by the dominant capacitive contribution and low charge-transfer resistance. The precursor-based lattice confinement strategy could be effective for constructing uniform composites as anode nanomaterials for electrochemical energy storage.

Rational construction of low-cost and high-performance electrocatalysts for water splitting is crucial for the advancement of renewable hydrogen fuel. Hybridizing heterojunctions or noble metals is one typical strategy used to boost the electrocatalytic performance for either the oxygen evolution reaction (OER) or hydrogen evolution reaction (HER). Here, low-content CeO x (3.74 wt%) is introduced into Ni 3 Fe nanoparticle-encapsulated carbon nanotubes (Ni 3 Fe@CNTs/CeO x ), with both the OER and HER activities boosted, as a bifunctional electrocatalyst for overall water splitting. The composite is derived by pyrolyzing a mixture of melamine/ternary NiFeCe-layered double hydroxide. The composite electrocatalyst requires low overpotentials of 195 and 125 mV at 10 mA cm -2 in 1.0 M KOH, respectively, which are superior to those of Ni 3 Fe@CNTs/NF (313 and 139 mV) and CeO x /NF (345 and 129 mV), and in particular, OER overpotentials of 320 and 370 mV at 50 and 100 mA cm -2 , respectively. Moreover, the composite-assembled electrolyzer for overall water splitting requires a current density of 10 mA cm -2 at a decent cell voltage of 1.641 V. Furthermore, the enhancement is elucidated by the synergistic effect: the dual role of CeO x in boosting the OER and HER, the highly conductive carbonaceous CNTs, large electrochemically active surface area and low charge-transfer resistance. The results can offer an effective route for designing and preparing low-cost and high-efficiency electrocatalysts for electrocatalytic water splitting.

O3-type layered oxides with high initial sodium content are promising cathode candidates for Na-ion batteries. However, affected by the undesired transition metal slab sliding and reaction with H 2 O/CO 2 , their further application is typically hindered by unsatisfactory cycling stability upon charging to high voltage and poor storage stability under humid air. Herein, we demonstrate a Fe/Ti cosubstitution strategy to simultaneously enhance the electrochemical performance and storage stability of pristine O3-NaNi 0.5 Mn 0.5 O 2 cathode material, via employing high redox potential and inactive stabilized dopants. The resultant Fe/Ti cosubstituted Na 0.95 Ni 0.40 Fe 0.15 Mn 0.3 Ti 0.15 O 2 undergoes highly reversible O3-P3-OP2 phase transitions with a small cell volume change of 2.8%, instead of complex O3-O'3-P3-P'3-P3'-O1 phase transitions in NaNi 0.5 Mn 0.5 O 2 . Consequently, the cathode displays a high specific capacity of 161.6 mAh g -1 with an average working voltage of 3.28 V and 81.8% capacity retention after 200 cycles at 5 C . Furthermore, the cathode material remains very stable after exposure to air for 7 days and even after soaking in water for 1 h, owing to the prohibition of sodium losing by elevating redox potential and contracting sodium layer spacing. This work proposes an effective method to enhance the electrochemical performance and storage stability of O3-type layered oxide cathodes and promises advancing Na-ion batteries toward large-scale industrialization.

Rational construction of nanosized anode nanomaterials is crucial to enhance the electrochemical performance of lithium-/sodium-ion batteries (LIBs/SIBs). Various anode nanoparticles are created mainly via templating surface confinement, or encapsulation within precursors (such as metal-organic frameworks). Herein, low-content SnO 2 nanodots on N-doped reduced graphene oxide (SnO 2 @N-rGO) were prepared as anode nanomaterials for LIBs and SIBs, via a distinctive lattice confinement of a CoAlSn-layered double hydroxide (CoAlSn-LDH) precursor. The SnO 2 @N-rGO composite exhibits the advantagous features of low-content (17.9 wt%) and uniform SnO 2 nanodots (3.0 ± 0.5 nm) resulting from the lattice confinement of the Co and Al species to the surrounded Sn within the same crystalline layer, and high-content conductive rGO. The SnO 2 @N-rGO composite delivers a highly reversible capacity of 1146.2 mA h g -1 after 100 cycles at 0.1 A g -1 for LIBs, and 387 mA h g -1 after 100 cycles at 0.1 A g -1 for SIBs, outperforming N-rGO. Furthermore, the dominant capacitive contribution and the rapid electronic and ionic transfer, as well as small volume variation, all give rise to the enhancement. Precursor-based lattice confinement could thus be an effective strategy for designing and preparing uniform nanodots as anode nanomaterials for electrochemical energy storage.

Sodium ion batteries (SIBs) have recently been promising in the large-scale electric energy storage system, due to the low cost, abundant sodium resources. Mn-based layered oxide cathode materials have been widely investigated, because of the high theoretical specific capacity, low cost, and abundant reserves. However, their development is limited by the problems of Jahn-Teller distortion, Na + /vacancy ordering, complex phase transitions, and irreversible anionic redox during cycling. Ion substitution strategy is one simple and effective way to regulate the crystal structure and boost sodium-storage performances of Mn-based cathode materials. In this review, we summarize the progress and mechanism of ion-substituted Mn-based oxides, establish a composition-crystal structure-electrochemical performance relationship, and also offer perspectives for guiding the design of high-performance Mn-based oxides for SIBs., (© 2022 The Chemical Society of Japan & Wiley-VCH GmbH.)

Rational design of high-capacity nanosized composites as anode nanomaterials is crucial to boosting electrochemical performances towards large-scale application for lithium- and sodium-ion batteries (LIBs and SIBs). The small sizes and homogeneous dimensional size distributions are achieved typically by either the surface confinement on the underlying supports, or the encapsulation confinement within the precursors (such as metal-organic frameworks). Herein, we report the ultrasmall NiS 2 nanodots on reduced graphene oxide (NiS 2 /N,S-rGO) synthesized via interlayer confinement as anode nanomaterials for LIBs and SIBs. The composite is synthesized by pyrolyzing a host/guest precursor of sodium dodecyl sulfate ion/[NiEDTA] 2- anions co-intercalated MgAl-layered double hydroxide LDH host, without additional sulfur source. The host/guest-derived interlayer nanoconfinement enables the composite to integrate the advantageous features: low-content active NiS 2 nanodots (11.0 wt%) with a mean size of 3.8 ± 0.5 nm, high-content N,S-rGO (89.0 wt%), as well as a large specific surface area and mesopore size distribution. The composite used as anode nanomaterial exhibits reversible capacities of 801.2 mAh g -1 after 100 cycles at 100 mA g -1 for LIBs, and 207.7 mAh g -1 after 200 cycles at 0.1 A g -1 for SIBs, which are greatly higher than those of the pristine N,S-rGO without NiS 2 nanodots. The enhancement is experimentally supported by the low charge transfer resistance, high capacitive-controlled contribution, and good structural stability. Our guest/host-based interlayer nanoconfinement can promise an effective synthesis strategy for designing various nanosized anodes for electrochemical energy storage., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Sodium-ion batteries (SIBs) are currently the most promising candidates for large-scale energy storage devices owing to their low cost and abundant resources. Titanium-based layered oxides have attracted widespread attention as promising anode materials due to delivering a safe potential of about 0.7 V (vs Na + /Na) and a small volume contraction during cycles; P2-type Ti-based layered oxides are typically reported, due to the challenging synthesis of the O3-type counterpart resulting from the high percentage of unstable Ti 3+ . Herein, we report an anomalous O3-Na 2/3 Ni 1/3 Ti 2/3 O 2 layered oxide as an ultrastable and high-rate anode material for SIBs. The anode material delivers a reversible capacity of 112 mA h g -1 after 300 cycles at 0.1 C, a good capacity retention rate of 91% after 1400 cycles at 2 C, and, in particular, a capacity of 52 mA h g -1 even at a high rate of 20 C (1780 mA g -1 ). Furthermore, the in situ X-ray diffraction monitoring reveals no phase transitions and almost zero strain both underlie the good long-cycle stability. The measured high apparent Na + diffusion coefficient (2.06 × 10 -10 cm 2 s -1 ) and the low migration energy barrier (0.59 eV) from density functional theory calculations are responsible for the superior rate capability. Our results promise advanced high-performance O3-type Ti-based layered oxides as promising anode materials toward application for SIBs.

O3-type sodium-layered oxides (such as antimony-based O3 structures) have been suggested as one of the most fascinating cathode materials for sodium-ion batteries (SIBs). Honeycomb-ordered antimony-based O3 structures, however, unsatisfactorily exhibit complex phase transitions and sluggish Na + kinetics during cycling. Herein, we prepared a completely cationic-disordered O3-type Na 0.8 Ni 0.6 Sb 0.4 O 2 compound by composition regulation for SIBs. Surprisingly, the measured redox potentials for typical O3-P3 phase transition are located at 3.4 V. Operando X-ray diffraction confirms a reversible phase transition process from the O3 to P3 structure accompanied with a very small volume change (1.0%) upon sodium extraction and insertion. The low activation barrier energy of 400 meV and the fast Na + migration of 10 -11 cm 2 ·s -1 are further obtained by first-principles calculations and galvanostatic intermittent titration technique, respectively. As a result, the O3-Na 0.8 Ni 0.6 Sb 0.4 O 2 cathode displays a reversible capacity of 106 mA h g -1 at 0.1C (12 mA g -1 ), smooth charge-discharge curves, and a high average working voltage of 3.5 V during battery cycling. The results highlight the importance of searching for a new O3-type structure with cation-disordering and high working voltage for realizing high energy SIBs.

Low-cost and stable sodium-layered oxides (such as P2- and O3-phases) are suggested as highly promising cathode materials for Na-ion batteries (NIBs). Biphasic hybridization, mainly involving P2/O3 and P2/P3 biphases, is typically used to boost their electrochemical performances. Herein, a P3/O3 intergrown layered oxide (Na 2/3 Ni 1/3 Mn 1/3 Ti 1/3 O 2 ) as high-rate and long-life cathode for NIBs via tuning the amounts of Ti substitution in Na 2/3 Ni 1/3 Mn 2/3- x Ti x O 2 (x = 0, 1/6, 1/3, 2/3) is demonstrated. The X-ray diffraction (XRD) Rietveld refinement and aberration-corrected scanning transmission electron microscopy show the co-existence of P3 and O3 phases, and density functional theory calculation corroborates the appearance of the anomalous O3 phase at the Ti substitution amount of 1/3. The P3/O3 biphasic cathode delivers an unexpected rate capability (≈88.7% of the initial capacity at a high rate of 5 C) and cycling stability (≈68.7% capacity retention after 2000 cycles at 1 C), superior to those of the sing phases P3-Na 2/3 Ni 1/3 Mn 2/3 O 2 , P3-Na 2/3 Ni 1/3 Mn 1/2 Ti 1/6 O 2 , and O3-Na 2/3 Ni 1/3 Ti 2/3 O 2 . The highly reversible structural evolution of the P3/O3 integrated cathode observed by ex situ XRD, ex situ X-ray absorption spectra, and the rapid Na + diffusion kinetics, underpin the enhancement. These results show the important role of P3/O3 biphasic hybridization in designing and engineering layered oxide cathodes for NIBs., (© 2021 Wiley-VCH GmbH.)

Eco-environmental synthesis of non-expensive electrocatalysts such as transition-metal phosphides (TMPs) is critical to advancing renewable hydrogen fuel. TMP nanostructures prepared typically by introducing additional conventional phosphorus sources are suggested as promising durable and low-cost electrocatalysts. Herein, an eco-efficient guest/host precursor-based synthesis route is demonstrated to prepare doped Co 2 P scaffolded within echinus-like carbon ((M 0.2 Co 0.8 ) 2 P@C, M = Fe and Ni) as electrocatalysts for overall water splitting. (Fe 0.2 Co 0.8 ) 2 P@C is derived by directly pyrolyzing a precursor of sodium dodecyl phosphate-intercalated CoFe-layered double hydroxide (CoFe-LDH), without introducing any additional phosphorus source. Electrocatalytic testing shows that (Fe 0.2 Co 0.8 ) 2 P@C requires overpotentials of 290 and 130 mV at a current density of 10 mA cm -2 for oxygen and hydrogen evolution reactions (OER and HER) in an alkaline electrolyte, respectively. Furthermore, a different (Ni 0.2 Co 0.8 ) 2 P@C composite, obtained only by altering a NiCo-LDH host, exhibits better electrocatalytic activities than those of Fe-doped (Fe 0.2 Co 0.8 ) 2 P@C. In particular, the (No 0.2 Co 0.8 ) 2 P@C||(Ni 0.2 Co 0.8 ) 2 P@C electrolyzer affords a current density of 10 mA cm -2 at a decent voltage of 1.62 V for overall water splitting. Electron energy-loss spectroscopy (EELS) observations show the oxyhydroxide layer formed on the surface, and density functional theory (DFT) calculations reveal that Fe-/Ni-doping lowers the Gibbs free energy barrier for the OER and the HER, both underpinning the enhancements.

Designing efficient and low-cost electrocatalysts for the hydrogen evolution reaction (HER) is of great importance to advance water splitting technology towards practical applications. Herein, we report the preparation of IrCo nanoparticles supported on nitrogen-doped carbon (IrCo/NC) as a HER electrocatalyst in acidic and alkaline electrolytes. The IrCo/NC composite is obtained by pyrolyzing an Ir-doped Co(OH)2 precursor on g-C3N4, and is endowed with N-doped carbon and uniform IrCo alloy nanoparticles via a crystal confinement resulting from the Ir-doping into the Co(OH)2 layer. Electrocatalytic analysis shows that the IrCo/NC electrode requires low overpotentials of 32 mV at 10 mA cm-2 in 0.5 M H2SO4 and 33 mV in 1 M KOH, which are superior to those of the Co/NC and IrCo alloys that are free of Ir-doping or N-doped carbon. The results provide a strategy for designing and preparing active noble-transition bimetallic alloy electrocatalysts as efficient HER catalysts.

The development of highly efficient and stable cathodes for sodium-ion batteries (SIBs) is strategically critical to achieving large-scale electrical energy storage. Creating air-stable and high-voltage layered cathodes for sodium-ion full batteries still remains a challenge. Herein, we describe a rational design and preparation of a stable P3-Na 2/3 Ni 1/4 Mg 1/12 Mn 2/3 O 2 cathode. The cathode displays a satisfactory working voltage of 3.6 V and excellent cyclic stability over 100 cycles at a 1 C rate without obvious capacity fading. The results of ex situ X-ray diffraction (XRD) demonstrate that the P3-type structure is well retained even when charged to 4.4 V. Furthermore, the structural characterization by XRD Rietveld refinement, scanning electron microscopy, and electrochemical testing certifies that the cathode maintains its structure commendably even when soaked in water for 12 h. In particular, the P3- Na 2/3 Ni 1/4 Mg 1/12 Mn 2/3 O 2 ∥hard carbon full battery exhibits a desired competitively high voltage of 3.45 V and an attractive energy density of up to 412.2 W h kg -1 based on the cathode. The comprehensive results achieved by the specially designed strategy provide guidance toward the exploration of stable cathodes in the application of SIBs as modern energy-storage devices.

Correction for 'NiS 2 nanodotted carnation-like CoS 2 for enhanced electrocatalytic water splitting' by Weili Xin et al., Chem. Commun., 2019, 55, 3781-3784.

Combining ultrasmall NiS2 nanodots with three-dimensional carnation-like CoS2 microstructures is demonstrated to be able to enhance the electrocatalytic activities for both the oxygen and hydrogen evolution reactions, leading to efficient overall alkaline water splitting.

Bimetallic sulfide ((Ni0.3Co0.7)9S8) nanoparticles confined by dual-carbon nanostructures are prepared by pyrolyzing a mixture of surfactant-intercalated layered double hydroxide and melamine, and deliver a highly reversible capacity and decent rate capability as anode nanomaterials for lithium- and sodium-ion batteries.

Exploring highly efficient and stable oxygen evolution reaction (OER) electrocatalysts such as transition-metal phosphides (TMPs) is critical to advancing renewable hydrogen fuel. TMP nanostructures typically involving binary or ternary TMPs tuned by cation or anion doping are suggested to be promising low-cost and durable OER catalysts. Herein, the preparation of CoP/CoP 2 composite nanoparticles encapsulated within N,P-doped carbon nanotubes (CoP/CoP 2 @NPCNTs) is demonstrated as a synergistic electrocatalyst for OER via the calcination of a CoAl-layered double hydroxide/melamine mixture and subsequent phosphorization. Facile visualization by scanning electron microscopy in conjunction with electron backscatter diffraction demonstrates the encapsulation of the CoP/CoP 2 nanoparticles within the N,P-codoped CNTs. Electrocatalytic evaluation shows that the composite electrode requires a low overpotential of 300 mV for the OER at 10 mA cm -2 in a 1.0 m KOH solution and, in particular, exhibits an excellent long-term durability of ≈100 h, which is superior to that of the state-of-the-art RuO 2 electrocatalyst. Density functional theory calculations reveal that the synergistic effect of CoP and CoP 2 can enhance the electrocatalytic performance. In addition, molecular dynamics simulations demonstrate that the generated O 2 molecules can readily diffuse out of the CNTs. Both the effects give rise to the observed OER enhancement., (© 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

We present a high throughput crop physiology condition monitoring system and corresponding monitoring method. The monitoring system can perform large-area chlorophyll fluorescence imaging and multispectral imaging. The monitoring method can determine the crop current condition continuously and non-destructively. We choose chlorophyll fluorescence parameters and relative reflectance of multispectral as the indicators of crop physiological status. Using tomato as experiment subject, the typical crop physiological stress, such as drought, nutrition deficiency and plant disease can be distinguished by the monitoring method. Furthermore, we have studied the correlation between the physiological indicators and the degree of stress. Besides realizing the continuous monitoring of crop physiology, the monitoring system and method provide the possibility of machine automatic diagnosis of the plant physiology. Highlights: A newly designed high throughput crop physiology monitoring system and the corresponding monitoring method are described in this study. Different types of stress can induce distinct fluorescence and spectral characteristics, which can be used to evaluate the physiological status of plants.

Transition-metal sulfides (TMSs) are suggested as promising electrode materials for electrochemical pseudocapacitors and lithium- and sodium-ion batteries; however, they typically involve mixed composites or conventionally stoichiometric TMSs (such as NiCo 2 S 4 and Ni 2 CoS 4 ). Herein we demonstrate a preparation of solid-solution sulfide (Ni 0.7 Co 0.3 )S 2 supported on three-dimensional graphene aerogel (3DGA) via a sulfuration of NiCo-layered double hydroxide (NiCo-LDH) precursor/3DGA. The electrochemical tests show that the (Ni 0.7 Co 0.3 )S 2 /3DGA electrode exhibits a capacitance of 2165 F g -1 at 1 A g -1 , 2055 F g -1 at 2 A g -1 , and 1478 F g -1 at 10 A g -1 ; preserves 78.5% capacitance retention upon 1000 cycles for pseudocapacitors; and in particular, possesses a relatively high charge capacity of 388.7 mA h g -1 after 50 cycles at 100 mA g -1 as anode nanomaterials for sodium-ion batteries. Furthermore, the electrochemical performances are readily tuned by varying the cationic type of the tunable LDH precursors to prepare different solid-solution sulfides, such as (Ni 0.7 Fe 0.3 )S 2 /3DGA and (Co 0.7 Fe 0.3 )S 2 /3DGA. Our results show that engineering LDH precursors can offer an alternative for preparing diverse transition-metal sulfides for energy storage.

For both field and greenhouse crops, it is challenging to evaluate their growth information on a large area over a long time. In this work, we developed a chlorophyll fluorescence imaging-based system for crop population growth information detection. Modular design was used to make the system provide high-intensity uniform illumination. This system can perform modulated chlorophyll fluorescence induction kinetics measurement and chlorophyll fluorescence parameter imaging over a large area of up to 45  cm×34  cm. The system can provide different lighting intensity by modulating the duty cycle of its control signal. Results of continuous monitoring of cucumbers in nitrogen deficiency show the system can reduce the judge error of crop physiological status and improve monitoring efficiency. Meanwhile, the system is promising in high throughput application scenarios.

Transition metal phosphide (TMP) nanostructures have stimulated increasing interest for use in water splitting owing to their abundant natural sources and high activity for the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER). Typically, the preparation of hierarchical TMPs involves the utilization of expensive or dangerous phosphorus sources, and, in particular, the understanding of topotactic transformations of the precursors to crystalline phases-which could be utilized to enhance electrocatalytic performance-remains very limited. We, herein, report a controllable preparation of CoP/CoP 2 nanoparticles well dispersed in flower-like Al 2 O 3 scaffolds (f-CoP/CoP 2 /Al 2 O 3 ) as a bifunctional electrocatalyst for the HER and OER via the phosphorization of a flower-like CoAl layered double hydroxide precursor. Characterization by in situ X-ray diffraction (XRD) monitored the topotactic transformation underlying the controllable formation of CoP/CoP 2 via tuning the phosphorization time. Electrocatalytic tests showed that an f-CoP/CoP 2 /Al 2 O 3 electrode exhibited a lower onset potential and higher electrocatalytic activity for the HER and OER in the same alkaline electrolyte than electrodes of flower-like and powdered CoP/Al 2 O 3 . The enhanced electrochemical performance was experimentally supported by measuring the electrochemically active surface area. The f-CoP/CoP 2 /Al 2 O 3 composite further generated a current density of 10 mA cm -2 at 1.65 V when used as a bifunctional catalyst for overall water splitting. Our results demonstrate that the preparation route based on the LDH precursor may provide an alternative for investigating diverse TMPs as bifunctional electrocatalysts for water splitting.

Developing effective heterogeneous metal catalysts with high selectivity and satisfactory activity for chemoselective hydrogenation of alkyne to alkene is of great importance in the chemical industry. Herein, we report our efforts to fabricate TiO 2 -supported Pd catalysts by a photodeposition method at room temperature for phenylacetylene semihydrogenation to styrene. The resulting Pd/TiO 2 catalyst, possessing smaller Pd ensembles with ambiguous lattice fringes and more low coordination Pd sites, exhibits higher styrene selectivity compared to two contrastive Pd/TiO 2 samples with larger ensembles and well-organized crystal structure fabricated by deposition-precipitation or photodeposition with subsequent thermal treatment at 300 °C. The sample derived from photodeposition exhibits greatly slow styrene hydrogenation in kinetic evaluation because the disordered structure of Pd particles in photodeposited Pd/TiO 2 may prevent the formation of β-hydride phases and probably produce more surface H atoms, which may favor high styrene selectivity., Competing Interests: The authors declare no competing financial interests.

Layered double hydroxides (LDHs), also known as hydrotalcite-like anionic clay compounds, have attracted increasing interest in electrochemical energy storage, in the main form of LDH precursor-derived transition metal oxides (TMOs). One typical approach to improve cycling stability of the LDH-derived TMOs is to introduce one- and two-dimensional conductive carbonaceous supports, such as carbon nanotubes and graphene. We herein demonstrate an effective approach to improve the electrochemical performances of well-dispersed biactive NiCo 2 S 4 /Ni 0.96 S as anode nanomaterials for lithium-ion batteries (LIBs), by introducing a three-dimensional graphene aerogel (3DGA) support. The resultant 3DGA supported NiCo 2 S 4 /Ni 0.96 S (3DGA/NCS) composite, obtained by sulfuration of NiCo-layered double hydroxide (NiCo-LDH) precursor in situ grown on the 3DGA support (3DGA/NiCo-LDH). Electrochemical tests show that the 3DGA/NCS composite indeed delivers the greatly enhanced electrochemical performances compared with the NiCo 2 S 4 /Ni 0.96 S counterpart on two-dimensional graphene aerogel, i.e., a high reversible capacity of 965 mA h g -1 after 200 cycles at 100 mA g -1 and especially a superlong cycling stability of 620 mA h g -1 after 800 cycles at 1 A g -1 . The enhancements could be ascribed to the compositional and structural advantages of boosting electrochemical performances: (i) well-dispersed NiCo 2 S 4 /Ni 0.96 S nanoparticles with interfacial nanodomains resulting from both the dual surface confinements of the 3DGA support and the crystallographic confinement of NiCo-well-arranged LDH crystalline layer, (ii) an appropriate specific surface area and a wide pore size distribution of mesopores and macropores, and (iii) highly conductive 3DGA support that is measured experimentally by using electrochemical impedance spectra to underlie the enhancement. Our results demonstrate that the tunable LDH precursor-derived synthesis route may be extended to prepare various transition metal sulfides and even transition metal phosphides for energy storage with the aid of tunable cationic type and molar ratio.

High efficient and sustainable utilization of water-based lubricant is essential for saving energy. In this paper, a kind of layered double hydroxide (LDH) nanoplatelets is synthesized and well dispersed in water due to the surface modification with oleylamine. The excellent tribological properties of the oleylamine-modified Ni-Al LDH (NiAl-LDH/OAm) nanoplatelets as water-based lubricant additives are evaluated by the tribological tests in an aqueous environment. The modified LDH nanoplatelets are found to not only reduce the friction but also enhance the wear resistance, compared with the water-based cutting fluid and lubricants containing other particle additives. By adding 0.5 wt% LDH nanoplatelets, under 1.5 GPa initial contact pressure, the friction coefficient, scar diameter, depth and width of the wear track dramatically decrease by 83.1%, 43.2%, 88.5% and 59.5%, respectively. It is considered that the sufficiently small size and the excellent dispersion of NiAl-LDH/OAm nanoplatelets in water are the key factors, so as to make them enter the contact area, form a lubricating film and prevent direct collision of asperity peaks. Our investigations demonstrate that the LDH nanoplatelet as a water-based lubricant additive has a great potential value in industrial application.

Low-content ultrathin coating of non-active alumina (Al2O3) has been extensively utilized as one of the most effective strategies to improve electrochemical performances of electrodes for lithium-ion batteries (LIBs), however, typically by employing expensive atomic layer deposition equipment. We herein demonstrate a simple preparation of high-content and well-dispersed Al2O3 (24.33wt.%)-containing multi-component composite (CoO/Co3O4/N-C/Al2O3) by calcination of melamine/CoAl-layered double hydroxide (CoAl-LDH) mixture. The resulting composite bundles the advantages expected to improve electrochemical performances: (i) bi-active CoO/Co3O4, (ii) highly conductive N-doped carbon, and (iii) N-doped carbon and high-content non-active Al2O3 as buffering reagents, as well as (iv) good distribution of bi- and non-active components resulted from the lattice orientation and confinement effect of the LDH layers. Electrochemical evaluation shows that the composite electrode delivers a highly enhanced reversible capacity of 1078mAhg(-1) after 50cycles at 100mAg(-1), compared with the bi-active CoO/Co3O4 mixtures with and without non-active Al2O3. Transmission electron microscopy/scanning electron microscopy observations and electrochemical impedance spectra experimentally provide the information on the good distributions of multiple components and the improved conductivity underlying the enhancements, respectively. Our LDH precursor-based preparation route may be extended to design and prepare various multi-component transition metal oxides for efficient lithium storage., (Copyright © 2015 Elsevier Inc. All rights reserved.)

Thin films of nickel-aluminum-containing layered double hydroxide (NiAl-LDH) have been prepared on nickel foil and nickel foam substrates by secondary (seeded) growth of NiAl-LDH seed layer. The preparation procedure consists of deposition of LDH seeds from a colloidal suspension on the substrate by dip coating, followed by hydrothermal treatment of the nanocrystals to form the LDH film. The secondary grown film is found to provide a higher crystallinity and more uniform composition of metal cations in the film layer than the in situ grown film on seed-free substrate under identical hydrothermal conditions. A systematic investigation of the film evolution process reveals that the crystallite growth rate is relatively fast for the secondary grown film because of the presence of LDH nanocrystal seeds. Electrochemical performance of the resulting NiAl-LDH films as positive electrode material was further assessed as an example of their practical applications. The secondary grown film electrode delivers improved recharge-discharge capacity and cycling stability compared with that of the in situ grown film, which can be explained by the existence of a unique microstructure of the former. Our findings show an example for the effective fabrication of LDH film with controllable microstructure and enhanced application performance through a secondary (seeded) growth procedure.

Development of a simple, reproducible and cost-effective protocol for mass production of non-precious-metal electrocatalysts for oxygen reduction reaction (ORR) is still challenging but highly desirable for their practical applications in industry. Herein, we developed a facile and scalable method to directly produce graphene (G) supported CoFe-LDHs and successfully used them as a precursor for mass production of Co/CoO/CoFe2O4/G as a low-cost and Pt-free efficient electrocatalyst, which exhibits comparable electrocatalytic activity and much better durability for ORR in comparison with commercial Pt/C catalysts. The result may provide a way for cost-effective production of ORR electrocatalysts on a large scale for practical applications.

Layered double hydroxides (LDHs), also called hydrotalcites, have been widely investigated for degradation of dye molecules, in the forms of direct photocatalysts, supports or precursors to ZnO-containing photocatalysts. LDH precursor-derived ZnO/ZnAl2O4 photocatalytic nanostructures have hitherto been created, involving ZnO/ZnAl2O4 powder and templated hierarchical frameworks with laboratory-scale preparations. We herein report a scalable preparation of ZnO/ZnAl2O4 microsphere derived from ZnAl-LDH precursor spray-dried microsphere. Survey of textural properties shows that ZnO/ZnAl2O4 microspheres maintain the hierarchically spherical feature and the relatively large surface area. Photocatalytic evaluation under UV irradiation shows that the ZnO/ZnAl2O4 microspheres exhibit highly enhanced photodegradation performance to methylene blue (MB) in comparison with the commercial ZnO powder. A preferential photodegradation to methyl orange (MO) of the MO/MB mixture was also observed, which was illustrated experimentally in terms of the favorable interaction and distribution between basic MO molecules and the acidic-site ZnO/ZnAl2O4 photocatalyst. Our results may initiate large-scale production of microspheres with promising photocatalytic performances., (Copyright © 2013 Elsevier Inc. All rights reserved.)

Films of laurate (La) anion-intercalated zinc-aluminum layered double hydroxides (ZnAl-La-LDHs) with hollow hemispherical protrusions on the surface of the hybrid film have been conveniently prepared by an ion-exchange reaction of a nitrate-containing LDH film previously grown in situ on a porous anodic alumina/aluminum (PAO/Al) substrate. No template is required to form the hemispherical protrusions, thus avoiding a complicated template removal process. The dimensions, morphology, and resistance to bursting of the hollow hemispherical protrusions can be easily tuned by varying the experimental conditions such as sodium laurate concentration, reaction time, and reaction temperature. The evolution of the hollow protrusions was investigated by scanning electron microscopy (SEM), and a "bubble template-reconfiguration assembly" mechanism, in which air bubbles on the film surface act as a template, has been proposed to explain their formation. When the ion-exchange reaction was carried out on a film that had been treated by ultrasound to eliminate surface air bubbles, no hemispherical protrusions were formed, which is consistent with the proposed mechanism., (Copyright © 2012 Elsevier Inc. All rights reserved.)

Layered double hydroxides (LDHs), known as a type of multifunctional anionic layered clay, typically exhibit stability and intrinsic hydrophilicity at neutral and alkaline pH. We herein report a polymer bead-templated preparation of flower-like LDH shell microspheres with the LDH platelets tuned under different aging durations and temperatures. Thickness of LDH shell walls was tuned readily by varying preparation conditions such as aging durations and temperatures. After a simple chemical surface modification using fluorine-silane molecule, the flower-like LDH nano/microspheres show the distinctly different transitions from the intrinsic hydropholicity to the superhydrophobicity at pH 2 and neutral pH. In contrast, at alkaline condition of pH 12 small flower-like spheres were formed atop of the parent microspheres, which may be argued in terms of a process of desorption of silane molecule at the alkaline condition combined with dissolution and reassembly of LDH platelets. Our finding of the superhydrophobic LDH spheres may find useful applications in chemical and biosensors against harsh acidic conditions.

CoO/CoFe(2)O(4) nanocomposites, derived from scalably prepared CoFe-layered double hydroxide (CoFe-LDH) single-resource precursors, exhibit tunable cycle performances and rate capabilities, which are supported by the homogenous dispersion of bi-component active CoO and CoFe(2)O(4) phases., (This journal is © The Royal Society of Chemistry 2012)

Layered double hydroxides (LDHs), also known as hydrotalcite-like anionic clays, have been investigated widely as promising electrochemical active materials. Due to the inherently weak conductivity, the electrochemical properties of LDHs were improved typically by utilization of either functional molecules intercalated between LDH interlayer galleries, or proteins confined between exfoliated LDH nanosheets. Here, we report a facile protocol to prepare NiAl-LDH/graphene (NiAl-LDH/G) nanocomposites using a conventional coprecipitation process under low-temperature conditions and subsequent reduction of the supporting graphene oxide. Electrochemical tests showed that the NiAl-LDH/G modified electrode exhibited highly enhanced electrochemical performance of dopamine electrooxidation in comparison with the pristine NiAl-LDH modified electrode. Results of high-resolution transmission electron microscopy and Raman spectra provide convincing information on the nanostructure and composition underlying the enhancement. Our results of the NiAl-LDH/G modified electrodes with the enhanced electrochemical performance may allow designing a variety of promising hybrid sensors via a simple and feasible approach.

Layered double hydroxides (LDHs), also known as hydrotalcite-like layered clays, have previously been investigated as a potential solid alkaline catalyst. A necessary calcinations/rehydration procedure, however, is utilized to enhance surface area and catalytic activity of LDHs involved. Here we report on a scalable preparation of sodium alginate-templated MgAI-LDH (LDH/SA) mesoporous composites with high surface area and surface acidity. The powdery LDH/SA mesoporous composites are prepared using alginate as template by a scalable method of separate nucleation and aging steps (SNAS). Comparison with the pristine MgAl-LDH shows that the obtained LDH/SA composites exhibit the greatly enhanced surface area and surface activity of surface acid sites at the elevated high temperatures which have scarcely been reported previously. Our results may allow designing a variety of mesoporous LDH-containing composites with potential applications in specific catalysis and purification processes.

Layered double hydroxides (LDHs), also well-known as hydrotalcite-like layered clays, have been widely investigated in the fields of catalysts and catalyst support, anion exchanger, electrical and optical functional materials, flame retardants and nanoadditives. This feature article focuses on the progress in micro-/nanostructured LDHs in terms of morphology, and also on the preparations, applications, and perspectives of the LDHs with different morphologies.

The performance of solid catalysts and catalyst supports is generally believed to be dependent on their morphology, surface area, and architecture. In order to fully exploit their attractive properties in actual practical applications, layered zirconium phosphate materials should be fabricated into macroscopic form. Here, we report the fabrication of microscopic spheres of alpha-zirconium phosphate (alpha-ZrP) by a spray-drying process. The layered alpha-ZrP nanoparticles were originally obtained using a synthesis route involving separate nucleation and aging steps (SNAS). The resulting products are composed of nanosize alpha-ZrP particles aggregated into solid microspheres with a diameter of 5-45 microm and a sphericity of 0.80. After calcination at 573 K, surface area of 43.8 m(2)/g could be obtained for alpha-ZrP microspheres, which is larger than that of the alpha-ZrP powder after similar thermal treatment (36.2 m(2)/g). Furthermore, the number of acidic sites of the alpha-ZrP microspheres is greater than for the alpha-ZrP powder due to its unique textual properties and higher surface area. The acylation reaction of fatty acid methyl esters (methyl stearate) with ethanolamine to form monoethanolamides was chosen as a probe reaction to evaluate the catalytic activity of the resulting microspherical alpha-ZrP materials, which showed high activity compared to the sample in the form of powders, with about 92.9% methyl stearate conversion at 393 K for 12 h. The enhanced performance in the reaction is determined by the large surface area and the increased number of acidic sites in the multiple-scales porosity of alpha-ZrP microspheres., (Copyright 2010 Elsevier Inc. All rights reserved.)

The in situ crystallization technique has been utilized to fabricate zirconium phenylphosphonate (ZrPP) films with their hexagonal crystallite perpendicular to the copper substrate. The micro/nano roughness surface structure, as well as the intrinsic hydrophobic characteristic of the surface functional groups, affords ZrPP films excellent hydrophobicity with water contact angle (CA) ranging from 134 degrees to 151 degrees , without any low-surface-energy modification. Particularly, in the corrosive solutions such as acidic or basic solutions over a wide pH from 2 to 12, no obvious fluctuation in CA was observed for all the ZrPP film. The k values of the hydrophobic ZrPP films are in the low-k range (k < 3.0), meeting the development of ultra-large-scale integration (ULSI) circuits. The hydrophobicity feature is proposed to bear ZrPP film a more stable low-k value in an ambient atmosphere. Besides, the polarization current of ZrPP films is reduced by 2 orders of magnitude, compared to that of the untreated copper substrate. Even deposited in a vacuum oven for 30 days at room temperature, ZrPP films also show excellent corrosion resistance, indicating a stable anticorrosion property.

Highly ordered transparent composite films of CdS and layered double hydroxides (LDHs) have been fabricated using a template synthesis method; the size of the CdS particles in the LDH host can be controlled by adjusting the length of time of the reaction with H(2)S.

MgAl-Layered double hydroxide (LDH) films with different orientations on the two sides of a glass substrate, one of which was modified with poly(vinyl alcohol), have been obtained by a one-step in situ hydrothermal crystallization method, and the growth mechanisms of the two films are discussed.

A zinc-aluminum layered double hydroxide (ZnAl-LDH)/alumina bilayer film has been fabricated on an aluminum substrate by a one-step hydrothermal crystallization method. The LDH film was uniform and compact. XRD patterns and SEM images showed that the LDH film was highly oriented with the c-axis of the crystallites parallel to the substrate surface. The alumina layer existing between the LDH film and the substrate was formed prior to the LDH during the crystallization process. Polarization measurements showed that the bilayer film exhibited a low corrosion current density value of 10(-8) A/cm(2), which means that the LDH/alumina bilayer film can effectively protect aluminum from corrosion. Electrochemical impedance spectroscopy (EIS) showed that the impedance of the bilayer was 16 MOmega, meaning that the film served as a passive layer with a high charge transfer resistance. The adhesion between the film and the substrate was very strong which enhances its potential for practical application.

We report on the mechanical characterization of individual mature amyloid fibrils by atomic force microscopy (AFM) and AFM-based single-molecule force spectroscopy (SMFS). These self-assembling materials, formed from the 29-residue amphiphatic peptide hormone glucagon, were found to display a reversible elastic behaviour. Based on AFM morphology and SMFS studies, we suggest that the observed elasticity is due to a force-induced conformational transition which is reversible due to the β-helical conformation of protofibrils, allowing a high degree of extension. The elastic properties of such mature fibrils contribute to their high stability, suggesting that the internal hydrophobic interactions of amyloid fibrils are likely to be of fundamental importance in the assembly of amyloid fibrils and therefore for the understanding of the progression of their associated pathogenic disorders. In addition, such biological amyloid fibril structures with highly stable mechanical properties can potentially be used to produce nanofibres (nanowires) that may be suitable for nanotechnological applications.

The self-organization of supramolecular structures, in particular gold-containing hydrogen-bonded rosettes, on highly oriented pyrolytic graphite (HOPG) surfaces was investigated by tapping-mode atomic force microscopy (TM-AFM) and scanning tunneling microscopy (STM). TM-AFM and high-resolution STM results show that these hydrogen-bonded assemblies self-organize to form highly ordered domains on HOPG surfaces. We find that a subtle change in one of the building blocks induces two different orientations of the assembly with respect to the surface. These results provide information on the control over the construction of supramolecular nanoarchitectures in 2D with the potential for the manufacturing of functional materials based on structural manipulation of molecular components.

Information on the interaction strength between small interfering RNA (siRNA) and chitosan can contribute to the understanding of the formation and stability of chitosan/siRNA nanoparticles used as siRNA delivery systems for gene silencing. In this study, we utilize atomic force microscopy to obtain force spectroscopy results of the interaction strengths between siRNA and chitosan measured in physiological phosphate buffered saline buffer at different pH. The force measurements revealed that the adhesive interactions decreased in force strength and force frequency as the pH was increased from 4.1 to 6.1, 7.4, and 9.5, exhibiting distinct multimodal distributions of the interaction forces between siRNA and chitosan molecules at acidic pH and only negligible adhesive forces were observed at neutral or high pH. The strong pH dependence of siRNA-chitosan interactions can provide a convincing rationale for siRNA/chitosan complex formation and nanoparticle stability under low acidic conditions. These findings demonstrate that the use of force spectroscopy for the adhesive force measurements allows an evaluation of the complexing ability between siRNA and chitosan that can be utilized to predict nanoparticle stability.

The binding of soluble proteins to target surfaces is vital in triggering the immune response. However, structural insight into such processes is still lacking. Mannan-binding lectin (MBL) is a classic example of a pattern recognition molecule with important roles in innate immunity against microbial infections. By small angle x-ray scattering analysis we show that the large MBL complex in solution is folded into a ramified structure with a striking rotational symmetry and a structure permissive of elongation by unbending. Nevertheless, the structure in solution is found to be very stable. However, when the MBL molecule interacts with surface-immobilized ligands, the stable MBL structure is broken into a stretched state with separation of the ligand-binding domains as shown by high resolution atomic force microscopy. These studies provide a snapshot of the single molecule mechanics of MBL and the first direct evidence that the transition from the soluble state to surface-bound protein involves large conformational changes in the quaternary structure, thus highlighting the role of surface topography in immune recognition.

By means of scanning tunneling microscopy (STM), we have observed for the first time well-ordered supramolecular nanopatterns formed by mixing two complementary DNA bases: adenine (A) and thymine (T), respectively, at the liquid/solid interface. By mixing A and T at a specific mixing molar ratio, cyclic structures that were distinctly different from the structures observed by the individual base molecules separately were formed. From an interplay between the STM findings and self-consistent charge density-functional based tight-binding (SCC-DFTB) calculation method, we suggest formation of A-T-A-T quartets constructed on the basis of A-T base pairing. The formation of the A-T-A-T quartets opens new avenues to use DNA base pairing as a way to form nanoscale surface architecture and biocompatible patterned surfaces particularly via host-guest complexation that might be suitable for drug design, where the target can be trapped inside the cavities of the molecular containers.