Metallic lithium (Li) is a promising anode material for next‐generation rechargeable batteries. However, the dendrite growth of Li and repeated formation of solid electrolyte interface during Li ...plating and stripping result in low Coulombic efficiency, internal short circuits, and capacity decay, hampering its practical application. In the development of stable Li metal anode, the current collector is recognized as a critical component to regulate Li plating. In this work, a lithiophilic Cu‐CuO‐Ni hybrid structure is synthesized as a current collector for Li metal anodes. The low overpotential of CuO for Li nucleation and the uniform Li+ ion flux induced by the formation of Cu nanowire arrays enable effective suppression of the growth of Li dendrites. Moreover, the surface Cu layer can act as a protective layer to enhance structural durability of the hybrid structure in long‐term running. As a result, the Cu‐CuO‐Ni hybrid structure achieves a Coulombic efficiency above 95% for more than 250 cycles at a current density of 1 mA cm−2 and 580 h (290 cycles) stable repeated Li plating and stripping in a symmetric cell.
A lithiophilic Cu‐CuO‐Ni hybrid structure is synthesized on a Ni foam substrate as a current collector for lithium (Li) metal anodes. The collective effects of low overpotential of the Cu‐CuO‐Ni hybrid structure for Li nucleation, nanowire array configuration, and the Cu buffer layer are demonstrated to be keys for achieving an outstanding overall performance of the current collector.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Using a mixed-method approach, this present study examined the roles of calling and the relation between life goals and spiritual values among early childhood professionals in New Zealand. Among the ...102 participants who completed the surveys, 24 participated in the follow-up individual interviews. In line with previous research, results showed that the five spiritual values—conformity, universalism, tradition, benevolence, and security—positively correlated with at least three intrinsic life goals, but showed a negative correlation with at least three of the four extrinsic goals. In addition, all non-spiritual values—self-direction, stimulation, hedonism, achievement, and power—correlated negatively with at least three of the intrinsic life goals. A similar pattern was found between the correlation between all non-spiritual values and extrinsic life goals. Interview data showed that participants who self-identified as having experienced a call to work with young children actively engaged with their calling
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They also affirmed that their calling was experienced at a deeply personal and emotional level. Participants also recognized the important impact of life goals, personal and spiritual values on their work. This paper concludes with implications for future research and practice.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
It is a challenge to synthesize all-in-one molecular networks that are autonomously self-healable over a wide temperature range (from subzero to high), transparent, stretchable, and conductive. Here ...we demonstrate the fabrication of self-healing, transparent, conductive, and highly stretchable elastomers by a photoinitiated copolymerization of two polymerizable deep eutectic solvent (PDES) monomers, acrylic amide (AAm)/choline chloride (ChCl) and maleic acid (MA)/ChCl type PDESs. Hydrogen bonds between binary building blocks of the poly(AAm/ChCl-co-MA/ChCl) system can readily break and reform, allowing such all organic designed elastomers to self-heal over a wide temperature ranging from −23 to 60 °C while keep a highly transparent appearance. The hypermolecular network elastomers showed a fast self-healing property (within 2 s) without any other external stimuli and excellent self-healing efficiency (up to 94%). The elastomers were highly transparent (an average transmittance of 95.1%), intrinsically conductive (an ionic conductivity of 4.0 × 10–4 S cm–1), and stretchable (strains up to 450%) at room temperature. We hypothesize that this behavior will find their potential use in display and/or optically related fields of stretchable electronics in harsh environments.
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IJS, KILJ, NUK, PNG, UL, UM
Scaling up to a large number of qubits with high-precision control is essential in the demonstrations of quantum computational advantage to exponentially outpace the classical hardware and ...algorithmic improvements. Here, we develop a two-dimensional programmable superconducting quantum processor, Zuchongzhi, which is composed of 66 functional qubits in a tunable coupling architecture. To characterize the performance of the whole system, we perform random quantum circuits sampling for benchmarking, up to a system size of 56 qubits and 20 cycles. The computational cost of the classical simulation of this task is estimated to be 2–3 orders of magnitude higher than the previous work on 53-qubit Sycamore processor Nature 574, 505 (2019). We estimate that the sampling task finished by Zuchongzhi in about 1.2 h will take the most powerful supercomputer at least 8 yr. Our work establishes an unambiguous quantum computational advantage that is infeasible for classical computation in a reasonable amount of time. The high-precision and programmable quantum computing platform opens a new door to explore novel many-body phenomena and implement complex quantum algorithms.
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CMK, CTK, FMFMET, IJS, NUK, PNG, UL, UM
This paper establishes the performance characteristics of convective–radiative longitudinal fins of rectangular, trapezoidal and concave parabolic profiles with simultaneous variation of thermal ...conductivity, heat transfer coefficient and surface emissivity with temperature. The convection and radiation sink temperatures were assumed to be non-zero. The calculations are carried out using the differential transformation method (DTM). The accuracy of the DTM is confirmed by comparing its predictions with the results from an analytical solution and a well-tested numerical procedure. A new idea of volume adjusted fin heat transfer rate, fin effectiveness, and fin efficiency is introduced to compare the performances of trapezoidal and concave parabolic fins with the rectangular fin. Results presented illustrate the effects of thermal conductivity parameter, emissivity parameter, convection–conduction parameter, radiation–conduction parameter, and dimensionless convection and radiation sink temperatures on the performance of fins.
► The paper investigates the performance characteristics of convective–radiative longitudinal fins with different profiles. ► The calculations are carried out using the differential transformation method which is a well-tested analytical technique. ► The comparison is based on a new idea of volume adjusted fin heat transfer rate, efficiency, and effectiveness. ► Volume adjusted results show that the concave parabolic fin provides the highest fin efficiency and fin effectiveness. ► There is an inverse relationship between the taper ratio of the fin and its local temperature.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
C-lignin is a homo-biopolymer, being made up of caffeyl alcohol exclusively. There is significant interest in developing efficient and selective catalyst for depolymerization of C-lignin, as it ...represents an ideal feedstock for producing catechol derivatives. Here we report an atomically dispersed Ru catalyst, which can serve as an efficient catalyst for the hydrogenolysis of C-lignin via the cleavage of C-O bonds in benzodioxane linkages, giving catechols in high yields with TONs up to 345. A unique selectivity to propenylcatechol (77%) is obtained, which is otherwise hard to achieve, because this catalyst is capable of hydrogenolysis rather than hydrogenation. This catalyst also demonstrates good reusability in C-lignin depolymerization. Detailed investigations by model compounds concluded that the pathways involving dehydration and/or dehydrogenation reactions are incompatible routes; we deduced that caffeyl alcohol generated via concurrent C-O bonds cleavage of benzodioxane unit may act as an intermediate in the C-lignin hydrogenolysis. Current demonstration validates that atomically dispersed metals can not only catalyze small molecules reactions, but also drive the transformation of abundant and renewable biopolymer.
Mixed transition metal oxides with hierarchical, porous structures, constructed from interconnected nano-building blocks, are considered promising positive electrodes for high-performance hybrid ...supercapacitors. Here we report our findings in design, fabrication, and characterization of 3D hierarchical, porous quaternary zinc-nickel-aluminum-cobalt oxide (ZNACO) architectures assembled from well-aligned nanosheets grown directly on nickel foam using a facile and scalable chemical bath deposition process followed by calcination. When tested as a binder-free electrode in a 3-electrode configuration, the ZNACO display high specific capacity (839.2Cg−1 at 1Ag−1) and outstanding rate capability (~82% capacity retention from 1Ag−1 to 20Ag−1), superior to those of binary-component NiCo2O4 and ZnCo2O4 as well as single-component Co3O4 electrode. More remarkably, a hybrid supercapacitor consisting of an as-fabricated ZNACO positive electrode and an activated carbon negative electrode exhibits a high energy density of 72.4Whkg−1 at a power density of 533Wkg−1 while maintaining excellent cycling stability (~90% capacitance retention after 10,000 cycles at 10Ag−1), demonstrating a promising potential for development of high-performance hybrid supercapacitors. Further, the unique electrode architecture is also applicable to other electrochemical systems such as batteries, fuel cells, and membrane reactors.
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•3D hierarchical porous Zn-Ni-Al-Co oxide (ZNACO) nanosheets grown directly on Ni foam is constructed for the first time.•The resultant binder-free electrodes manifest outstanding electrochemical performances with high capacity, excellent rate capability and cycling stability.•The synergetic contribution and advantageously structural features contribute to outstanding capacitive performance.•The assembled ZNACO//AC hybrid supercapacitor achieved a remarkable energy density of 72.4Whkg−1 at a power density of 533Wkg−1.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
Herein, we propose an effective strategy to enhance the electrochemical activity of a metal organic framework-based (MOF) electrode material for electrochemical capacitors. The fabrication involves ...the synthesis of CuO nanowires on a Cu substrate through a facile solution-free dry oxidation route followed by the deposition of an oriented Ni-Co-zeolitic imidazolate framework (Ni-Co-ZIF) on 1D CuO. This synthesis strategy benefitted from the highly exposed redox active sites of the aligned Ni-Co-ZIF, an "ion and electrolyte repository", to assist the diffusion of electrolyte ions, and a p-n heterojunction between CuO and the Ni-Co-ZIF. ZIFs represent an emerging and unique class of MOFs. The oriented pseudocapacitive Ni-Co-ZIF@CuO composite electrode yielded excellent electrochemical merits including a high gravimetric capacitance which is 3.3- and 2.1-fold higher than those of the self-supported CuO and bulk MOF, respectively. Furthermore, we employed first principles density functional theory calculations to study the enhanced electronic conductivity and reduced work function of Ni-Co-ZIF@CuO systems upon CuO doping, which reinforced the experimental findings. Moreover, an asymmetric supercapacitor (ASC) device was assembled to evaluate the application of the as-fabricated electrode material for electrochemical capacitors. The gadget delivered a maximum energy density of 43 W h kg
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, with improved cycling stability after 10 000 cycles. The oriented Ni-Co-ZIF@CuO with remarkable electrochemical activity and mechanical flexibility inspires for next-generation MOF-based electrode materials with superior electrochemical attributes.
We proposed an effective strategy to address the structural limitations of metal organic frameworks for energy storage devices. An oriented n-type Ni-Co-MOF was grown on solution-free p-type CuO nanowires.
Nickel foam supported hierarchical mesoporous Zn–Ni–Co ternary oxide (ZNCO) nanowire arrays are synthesized by a simple two-step approach including a hydrothermal method and subsequent calcination ...process and directly utilized for supercapacitive investigation for the first time. The nickel foam supported hierarchical mesoporous ZNCO nanowire arrays possess an ultrahigh specific capacitance value of 2481.8 F g–1 at 1 A g–1 and excellent rate capability of about 91.9% capacitance retention at 5 A g–1. More importantly, an asymmetric supercapacitor with a high energy density (35.6 Wh kg–1) and remarkable cycle stability performance (94% capacitance retention over 3000 cycles) is assembled successfully by employing the ZNCO electrode as positive electrode and activated carbon as negative electrode. The remarkable electrochemical behaviors demonstrate that the nickel foam supported hierarchical mesoporous ZNCO nanowire array electrodes are highly desirable for application as advanced supercapacitor electrodes.
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IJS, KILJ, NUK, PNG, UL, UM
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