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Background: An accurate perception of death risk is a prerequisite for advanced cancer patients to make informed end-of-life care decisions. However, there is to date no suitable scale to measure death risk perception. This study was to develop and psychometrically test the death risk perception scale (DRPS) for advanced cancer patients. Methods: Process of instrument development and psychometric evaluation were used. First, qualitative research, a literature review, brainstorming, a Delphi study, and cognitive interviews were conducted to construct a pretest scale of death risk perception. Second, a scale-based survey was administered to 479 advanced cancer patients. Item, exploratory factor, and confirmatory factor analyses were employed to optimize the scale. The Cronbach's alpha was calculated as a reliability analysis. The validity analysis included construct, convergent, discriminant, and content validity values. Results: A three-dimension, 12-item scale was developed, including deliberative, affective, and experiential risk perception. The confirmatory factor analysis supported the three-factor model with satisfactory convergent and discriminant validity levels. The Cronbach's alpha coefficient for internal consistency was 0.807 and scale-level content validity index was 0.98. Conclusions: The 12-item DRPS is a reliable and valid instrument for assessing the level of death risk perception in advanced cancer patients. More studies are needed to examine its structure and robustness prior to use. [ABSTRACT FROM AUTHOR]

Background: An accurate perception of death risk is a prerequisite for advanced cancer patients to make informed end-of-life care decisions. However, there is to date no suitable scale to measure death risk perception. This study was to develop and psychometrically test the death risk perception scale (DRPS) for advanced cancer patients. Methods: Process of instrument development and psychometric evaluation were used. First, qualitative research, a literature review, brainstorming, a Delphi study, and cognitive interviews were conducted to construct a pretest scale of death risk perception. Second, a scale-based survey was administered to 479 advanced cancer patients. Item, exploratory factor, and confirmatory factor analyses were employed to optimize the scale. The Cronbach's alpha was calculated as a reliability analysis. The validity analysis included construct, convergent, discriminant, and content validity values. Results: A three-dimension, 12-item scale was developed, including deliberative, affective, and experiential risk perception. The confirmatory factor analysis supported the three-factor model with satisfactory convergent and discriminant validity levels. The Cronbach's alpha coefficient for internal consistency was 0.807 and scale-level content validity index was 0.98. Conclusions: The 12-item DRPS is a reliable and valid instrument for assessing the level of death risk perception in advanced cancer patients. More studies are needed to examine its structure and robustness prior to use. [ABSTRACT FROM AUTHOR]

Birefringent materials play a key role in modulating the polarization of light and thus in optical communication as well as in laser techniques and science. Designing new, excellent birefringent materials remains a challenge. In this work, we designed and synthesized the first antimony(III) fluoride oxalate birefringent material, KSb2C2O4F5, by a combination of delocalized π‐conjugated [C2O4]2− groups, stereochemical active Sb3+ cations, and the most electronegative element, fluorine. The [C2O4]2− groups are not in an optimal arrangement in the crystal structure of KSb2C2O4F5; nonetheless, KSb2C2O4F5 exhibits a large birefringence (Δn=0.170 at 546 nm) that is even better than that of the well‐known commercial birefringent material α‐BaB2O4, even though the latter features an optimal arrangement of π‐conjugated [B3O6]3− groups. Based on first‐principles calculations, this prominent birefringence should be attributed to the alliance of planar π‐conjugated [C2O4]2− anions, highly distorted SbO2F2 and SbOF3 polyhedra with a stereochemically active lone pair. The combination of lone‐pair electrons and π‐conjugated systems boosts the birefringence to a large extent and will help the development of high‐performance birefringent materials. [ABSTRACT FROM AUTHOR]

To meet the demands in portable electronic devices, electric vehicles and stationary energy storage, it is necessary to prepare advanced lithium ion batteries (LIBs) with high energy density and fast charge and discharge capabilities. Cathode materials, which account for 40%–50% of the cost of a whole battery, play a decisive role in cell voltage and capacity. Moreover, the performances of the cathodes are also balanced by many other aspects, including cycle life, rate capability, safety, costs, and environmental benignity. Unfortunately, none of the currently available cathode materials (e.g. LiFePO4, LiNixCoyMn1−x−yO2 layered oxides and Li-rich layered oxides) can get all the quests in a single cell. The electrochemical performances of a cathode are closely connected with its structural features, such as the porosities, morphologies and specifically exposed surfaces, which can be tuned by delicate designs. Here, we review our work on the rational design and delicate preparation of a series of cathode materials with controllable microstructures. We reveal the synergistic effects of both reaction and mass transfer on the formation of these meso-scale structures and the improved electrochemical performances of the cathode materials. The review will provide a scientific basis for the large-scale production of meso-scale structured cathode materials, and lay theoretical and experimental foundation for the application of cathode materials in next-generation LIBs. [ABSTRACT FROM AUTHOR]

Abstract Nowadays nickel-rich LiNi x Co y Mn 1-x-y O 2 (0.5 < x < 1) cathode materials attract great research interests due to their high specific capacity in lithium ion batteries. However, poor cycling performance and serious safety concerns trade off their benefits. Here, we present an effective etching-induced coating strategy for surface modification of LiNi 0.8 Co 0.1 Mn 0.1 O 2 cathode materials by LiAlO 2. Hydrolysis of AlCl 3 creates H+ to etch the hydroxide precursor of LiNi 0.8 Co 0.1 Mn 0.1 O 2 and to induce oriented deposition of Al(OH) 3 layer on surface of the hydroxide precursor, which is transformed into uniform γ-LiAlO 2 coating on the LiNi 0.8 Co 0.1 Mn 0.1 O 2 particles after the subsequent lithium impregnating and annealing. The 2.2 wt% LiAlO 2 -coated LiNi 0.8 Co 0.1 Mn 0.1 O 2 cathode delivers a high rate capacity of 135.2 mAh g−1 at 10 C and long cyclability with capacity retention of 85.8% after 200 cycles at 0.5 C. In addition, the thermal stability of LiAlO 2 -coated LiNi 0.8 Co 0.1 Mn 0.1 O 2 is significantly improved. The enhanced battery performances are due to partial Al3+ doping and Li+ conductive LiAlO 2 coating layer that provides well-connected networks for Li+ transport, improves the structural stability and prevents core materials from the attack by side products. Graphical abstract The detailed etching-induced coating strategy for the synthesis of LiAlO 2 -coated NCM811 materials. Image 1 Highlights • The etching-induced coating strategy was designed to prepare LiAlO 2 -coated NCM811. • The modified NCM811 exhibits better rate and cycle performance. • The modified NCM811 displays smaller overpotential especially at high rate. • The coating of LiAlO 2 significantly improves the thermal stability of NCM811. [ABSTRACT FROM AUTHOR]

The synthesis of one-dimensional (1D) Zn-Mn-Oxide (ZMO) for lithium storage is an important research topic, since ZMO can potentially satisfy the ever-increasing demand on the high energy density, natural abundance and long lifespan of lithium ion batteries. Generally, the synthesis of 1D ZMO nanostructures relies on various templates. A facile construction of 1D ZMO nanostructures with tunable compositions via the same synthetic protocol remains a great challenge. Herein, two different Zn-Mn-Oxides of ZnMn 2 O 4 and ZnMnO 3 both with 1D rod morphology were successfully prepared via a simple co-precipitation reaction coupled with subsequent heat treatment. As the anode materials for lithium ion battery, both ZMO nanorods exhibit good lithium storage performances. Especially, ZnMn 2 O 4 nanorods display superior electrochemical performances to ZnMnO 3 nanorods, including higher discharge capacities of 1119.3 and 572.6 mAh g −1 at 0.1 C and 0.5 C, respectively and better cyclability with capacity retention of 80% after 300 cycles at 0.5 C. The improved electrochemical properties should be attributed to the porous and interparticle-bridging microstructures in ZnMn 2 O 4 nanorods, which can offer better contact between electrolyte and anode and tolerate larger volume changes during discharge/charge process. [ABSTRACT FROM AUTHOR]

Cyclohexanone is an important intermediate for the fabrication of synthetic polymers such as Nylon in chemical industry. A green synthesis of cyclohexanone under mild conditions using environmental friendly oxidants and non-precious catalysts is highly desired. Herein, one-dimensional crystalline h-WO nanorods have been synthesized via a facile hydrothermal method. The h-WO nanorods are assembled by the closely packed and highly aligned thin nanowires with the lengths up to 10 μm and diameters of about 10 nm, growing along the [001] direction. The h-WO nanorods are used as the catalyst for the first time in the selective oxidation of cyclohexanol to cyclohexanone by aqueous hydrogen peroxide. The effective catalysis by h-WO nanorods remarkably increases the yield of cyclohexanone from 3.1 to 78.6 %, under the mild conditions (80 °C, ambient pressure). With a high recyclability, the h-WO nanorods have shown great potentials in green chemistry for the synthesis of cyclohexanone by the catalytic oxidation of cylohexanol. Graphical Abstract: [ABSTRACT FROM AUTHOR]

Deposition technology of transparentconducting oxide (TCO) thinfilms is critical for high performance of optoelectronic devices.Solution-based fabrication methods can result in substantial costreduction and enable broad applicability of the TCO thin films. Herewe report a simple and highly effective solution process to fabricateindium–tin oxide (ITO) thin films with high uniformity, reproducibility,and scalability. The ITO films are highly transparent (90.2%) andconductive (ρ = 7.2 × 10–4Ω·cm)with the highest figure of merit (1.19 × 10–2Ω–1) among all the solution-processed ITOfilms reported to date. The high transparency and figure of merit,low sheet resistance (30 Ω/sq), and roughness (1.14 nm) arecomparable with the benchmark properties of dc sputtering and canmeet the requirements for most practical applications. [ABSTRACT FROM AUTHOR]

Abstract: Ag3CuS2 nanocages were successfully fabricated for the first time via a convenient ion-exchange route by Ag+ reacting with Cu7S4 18-facet hollow nanopolyhedra. The average size and shell thickness of Ag3CuS2 nanocages were around 400 and 30nm, respectively. Room-temperature response of Ag3CuS2 nanocages to ammonia was investigated by photoluminescence-type sensor. Sensing results suggested that these hollow-structured Ag3CuS2 exhibited better performances including higher sensitivity, shorter response and recovery time than their rod-shape counterparts. A possible hole trapping mechanism was proposed. [Copyright &y& Elsevier]

A correction to the article "BMC Palliat Care 23, 136 (2024)" in the BMC Palliative Care issue discusses the addition of equal contribution acknowledgment for the first and second authors, Guojuan Chen and Xiaoling Zhang.

• A PVP-bridged coating strategy was designed to prepare the LMR@γ-LAO composite. • γ-LiAlO 2 coating layer leads to a higher Li+ diffusion coefficient of the cathode. • γ-LiAlO 2 coating layer enhances the thermal stability of the cathode. • DFT calculation proves a lower Li+ diffusion energy barrier in γ-LiAlO 2. Li-rich layered materials have been considered as promising cathode materials for next-generation lithium-ion batteries due to their high capacity (≥250 mAh g−1). Unfortunately, this type of cathode material still suffers from intrinsic deficiencies of capacity fading and side reactions. Surface coating with a protective layer can resolve the above problems to some extent, whereas normal coating strategies still suffer from process complexity and are difficult to prevent phase separation that leads to the formation of an independent miscellaneous phase. Herein, we report an effective PVP-bridged coating method, in which the PVP molecules can bridge the gap between the coating shell and the electrode material core through hydrogen bonding and functional groups. Utilizing this strategy, a uniform Li-ion conductor γ-LiAlO 2 nanolayer with a thickness of 7 nm is successfully formed on the surface of the Li 1.2 Ni 0.182 Co 0.08 Mn 0.538 O 2 cathode material, which leads to an excellent rate capability (177.0 mAh g−1 delivered at 5 C) and superior cycling stability (89.3% capacity retention achieved after 100 cycles at 10 C) for the composite material. Furthermore, the exothermic reaction for the composite material takes place at a higher temperature (234.1 °C) relative to the uncoated sample (220.9 °C), implying its improved thermal stability. Galvanostatic intermittent titration technique and density functional theory calculation demonstrate a higher Li+ diffusion coefficient for the γ-LiAlO 2 coated sample and a lower Li+ diffusion energy barrier in γ-LiAlO 2. Based on the promising results, the PVP-bridged coating strategy presented in this study provides a new perspective in material design towards high-performance Li-rich cathode materials for lithium-ion batteries. [ABSTRACT FROM AUTHOR]

Tungsten oxide has a wide range of applications in chromic devices and catalysis. Effective control over the morphology of tungsten oxide remains a major challenge. Here, we present a facile pH-controlled strategy for synthesizing three-dimensional tungsten oxide architectures with different morphologies without using any templates or surfactants. These hierarchical architectures with rod-like, disk-like and sphere-like morphologies are assembled from one-dimensional tungsten oxide nanowires/nanorods. The influence of the single parameter of the pH value on the morphologies and crystal structures of tungsten oxide is systematically studied. The results indicate that different polytungstate anions obtained at various pH values give rise to different crystal nuclei by a dehydration process. These crystal nuclei grow into similar phases (crystal structures) but distinct morphologies via hydrothermal treatment. Here, the similarity of the crystal structures of h-WO3 and o-WO3·0.33H2O plays a key role in the structural transformation. Further experiments show that these three-dimensional tungsten oxide architectures display promising applications as catalysts in green chemistry for the oxidation of cyclohexene to adipic acid using an environmentally friendly oxidant (hydrogen peroxide). [ABSTRACT FROM AUTHOR]

The dual-site doping method combines three-fold benefits to enhance LiNi 0.9 Co 0.1 O 2 stability. [Display omitted] • A new Mg/Ta dual-site doping strategy was proposed for high-nickel LiNi 0.9 Co 0.1 O 2. • Mg2+ and Ta5+ ions reside in the 3a and 3b crystallographic sites respectively. • Mg2+ ions prevent Li+/Ni2+ anti-site exchange and inhibit detrimental phase transition. • Ta5+ ions expand layer spacing and induce LiTaO 3 surface coating and well-ordered structure. • The dual-site doping method combines three-fold benefits to enhance LiNi 0.9 Co 0.1 O 2 stability. Due to its high specific capacity and low cost, high-nickel layered oxide LiNi 0.9 Co 0.1 O 2 has found promising application as the cathode materials for lithium-ion batteries. However, the crystallographic instability induced by Li+/Ni2+ anti-site exchange, the interfacial parasitic reactions and the microcracking caused by internal stress jointly contribute to the mechano-chemical failure of LiNi 0.9 Co 0.1 O 2 , leading to its fast capacity decay and high thermal stability concern. In this regard, a Mg/Ta dual-site doping strategy was proposed for LiNi 0.9 Co 0.1 O 2 , for which Mg2+ was doped in situ during the synthesis of cathode precursor, while Ta5+ ions were incorporated after the precursor synthesis. This novel synthesis approach leads to unique dual-site occupations of Mg2+ and Ta5+ in the 3a and 3b crystallographic sites respectively. The Mg2+ ions residing in 3a site can function as pillar ions by preventing the Li+/Ni2+ anti-site exchange and inhibiting layered to rock-salt phase transition. The Ta5+ ions occupying 3b site not only leads to the expanded lithium layer spacing but also creates interfacial protection and well-ordered microstructure in LiNi 0.9 Co 0.1 O 2. Consequently, the dual-site-doped LiNi 0.9 Co 0.1 O 2 outperforms the pristine and single-site-doped samples. For instance, its full cell shows a greatly enhanced cycling stability from 57.3 % to 90.5 % after 300 cycles at 1C/1C and well improved thermal stability from 205.2 °C to 225.6 °C, compared to the pristine sample. This Mg/Ta dual-site doping strategy provides a facile and practical way to improve the electrochemical and thermal performances of high-nickel layered cathode material LiNi 0.9 Co 0.1 O 2. [ABSTRACT FROM AUTHOR]

Abstract Exploring electrode materials with high energy density is crucial for the application of electrochemical energy storage. Herein, we innovatively synthesized frisbee-shaped architecture of h -WO 3 ·nH 2 O by a simple hydrothermal method, which is assembled by nanorods of ∼80 nm in diameter, with structural water storing in the open hexagonal tunnels via a template-free strategy for supercapacitor application. This electrode material possesses high specific capacitance of 391 F g−1 at 0.5 A g−1, superior rate capacity of 298 F g−1 at 10 A g−1, and almost 100% capacitance retention after 2000 cycles at 10 A g−1, which can be ascribed to its unique hierarchical micro/nanostructure and water chains within the channels of crystalline h -WO 3. The unique self-assembled frisbee-shaped micro/nanostructure can avoid further aggregation of nanosized building blocks and allow sufficient ions accessible surface, beneficial to increasing deliverable capacity. Notably, the presence of structural water also offers fast hydrated protons transport pathway, resulting in high capacity and good stability at high rate. Graphical abstract Image 1 Highlights • Hierarchical h -WO 3 ·0.28H 2 O has been successfully prepared by a hydrothermal method. • The WO 3 assembly with nanorods has structural water in the hexagonal channels. • The WO 3 shows superior electrochemical performance as supercapacitor electrode. [ABSTRACT FROM AUTHOR]

[Display omitted] • PEO-based polymer-in-salt electrolytes are made by a facile coating process. • Rich hydrogen bonds are formed in polymer network for better structural stability. • High content of free Li+ and restricted anion movement obtain a high t Li + of 0.639. • Inhibition of Li dendrites renders Li/Li cells cycling over 3000 h at 0.2 mA cm−2. • The electrolytes boost the performances of LMBs using LFP or NCM88 significantly. Polyethylene oxide (PEO)-based solid polymer electrolyte (SPEs) is full of attraction due to its exceptional lithium ion dissolubility and strong resistance toward lithium metal reduction. Nevertheless, it still suffers from the unfulfilling room temperature ionic conductivity and poor mechanical properties. Herein, a flexible and robust polymer-in-salt electrolyte based on composite of polybenzimidazole (PBI) and PEO via a facile preparation approach has been developed for room-temperature lithium metal batteries (LMBs). The rigid framework structure of PBI and dense hydrogen bonds formed between PBI and PEO jointly reinforce the structural stability of SPEs at high lithium salt concentration, which makes the SPEs possess sufficient mechanical properties to resist the lithium dendrites growth. The thermal stability and fire resistance of SPEs have also been improved relying on the distinctive flame retardancy and incombustibility of PBI. Besides, PBI is prone to forming hydrogen bonds with lithium salt anions to limit their mobility, while the rich N atoms on PBI chains can promote the dissociation of lithium salt through electrostatic attraction interaction. Their synergistic effects make the PEO-based polymer-in-salt electrolytes achieve the high room temperature ionic conductivity of 5.7 × 10−4 S cm−1, wide electrochemical window of 4.45 V, and large lithium transference number of 0.639. When applied to LMBs with LiFePO 4 or LiNi 0.88 Co 0.06 Mn 0.06 O 2 cathode, both coin cells exhibit improved cycling performance and rate capability. Furthermore, the LiNi 0.88 Co 0.06 Mn 0.06 O 2 /SiO x -C pouch cells using the SPEs demonstrate remarkable flexibility and safety, clarifying that the PEO-based polymer-in-salt electrolytes possess a promising application prospect for safe and high-performance LMBs. [ABSTRACT FROM AUTHOR]

Lithium-rich layered compound cathode materials recently attract ever-growing attention in lithium ion batteries for electric vehicles and energy storage devices due to their high discharge capacities of over 250 mAh g −1 and low cost. However, they still suffer from capacity fade, voltage decay and poor rate capability and thermal stability. In this paper, the Al&F co-doped Li 1.2 Ni 0.13 Co 0.13- x Mn 0.54 Al x O 2(1- y ) F 2 y cathode material has been successfully prepared via a co-precipitation reaction and a subsequent solid phase calcination. The resulting material combines the advantages of both Al-doping and F-doping, which can effectively mitigate the intrinsic layered-to-spinel phase transformation, and as a consequence, inhibits the capacity fade and voltage decay: delivering a discharge capacity of 217 mAh g −1 with retention of 88.21% and an average discharge voltage decay of 0.4019 V upon 150 cycling at 0.5 C. On the other side, with an increased electronic and ionic conductivity, this co-doping practice enhances the rate capability by a considerable extent that it delivers a discharge capacity of 157 mAh g −1 at 10 C, thus facilitating its application for quick charging devices. In addition, the thermal stability related with battery safety is significantly meliorated. Specifically, the co-doped cathode material exhibits an initial exothermal peak at a higher temperature of 273 °C and a much less overall heat generation of 221 J g −1 compared to the 210 °C and 755 J g −1 for the pristine one. In conclusion, the anion/cation co-substitution strategy has been demonstrated to be of great promise for the improvement of lithium-rich layered cathode materials. [ABSTRACT FROM AUTHOR]

Hierarchical array catalysts with micro/nano structures on substrates not only possess high reactivity from large surface area and suitable interface, but intensify mass transfer through shortening the diffusion paths of both reactants and products for high catalytic efficiency. Herein, we first demonstrate fabrication of Fe 2 O 3 hierarchical arrays grown on stainless-steel substrates via in-situ hydrothermal chemical oxidation followed by heat treatment in N 2 atmosphere. As a Fenton-like catalyst, Fe 2 O 3 hierarchical arrays exhibit excellent catalytic activity and life cycle performance for methylene blue (MB) dye degradation in aqueous solution in the presence of H 2 O 2 . The Fe 2 O 3 catalyst with unique hierarchical structures and efficient transport channels, effectively activates H 2 O 2 to generate large quantity of •OH radicals and highly promotes reaction kinetics between MB and •OH radicals. Immobilization of hierarchical array catalysts on stainless-steel can prevent particles agglomeration, facilitate the recovery and reuse of the catalysts, which is expected promising applications in wastewater remediation. [ABSTRACT FROM AUTHOR]

It’s significant to find an atom-economic way to prepare graphene-manganese oxide nanocomposites for supercapacitors. Herein, a highly atom-efficient strategy is reported to synthesize reduced graphene oxide (rGO)-Mn 3 O 4 nanoparticles composite for supercapacitors. First, rGO/MnSO 4 suspension is obtained by hydrothermal reduction of graphene oxide (GO)/MnSO 4 suspension, which is directly produced via Hummers method, and then rGO-Mn 3 O 4 nanoparticles composites are prepared by precipitation of Mn 3 O 4 nanoparticles anchored in-situ on rGO sheets. The as-prepared rGO-Mn 3 O 4 nanocomposites with 86.96% Mn 3 O 4 exhibit high specific capacitance of 258.6 F g −1 and 186.2 F g −1 at 0.25 A g −1 , when using 2 M KOH and 1 M Na 2 SO 4 solution as electrolyte, respectively. More importantly, with the wastewater recovered in the preparation process as electrolyte, the rGO-Mn 3 O 4 composites can deliver a high specific capacitance of 221.6 F g −1 at 50 mA g −1 and 97.1% of the initial capacitance is retained after 1000 cycles at 1 A g −1 . In addition, the rGO-MnO 2 nanosheets composites can also be obtained via a similar strategy. Obviously, this work provides an atom-efficient way for preparation of rGO-manganese oxide nanocomposites for supercapacitors by fully utilizing effective components of the reaction system, including the wastewater. [ABSTRACT FROM AUTHOR]

We report here a novel proton exchange membrane with remarkably high methanol-permeation resistivity and excellent proton conductivity enabled by carefully designed self-assembled ionic conductive channels. A direct methanol fuel cell utilizing the membrane performs well with a 20 M methanol solution, very close to the concentration of neat methanol. [ABSTRACT FROM AUTHOR]

We design and successfully synthesize non-fluorinated polyamides with controlled crosslinking using sulfonimide as a bi-functional linker to interconnect polymer backbones and as a bridge for proton conduction. We show that the bi-functional linkers are highly beneficial not only for mechanical enforcement of the proton exchange membranes but also for enhancement of water retention capacity. With an appropriate degree of crosslinking, higher water retention capacity than that of commercial Nafion membranes can be obtained. The maximum proton conductivity of the membranes is found to be as high as 0.139 S cm −1 at 80 °C, almost the same as that of a Nafion 117 membrane. Excellent performance with the bi-functional polymer membranes in an air-breathing direct methanol fuel cell prototype, comparable to the performance of a Nafion 117 membrane, is demonstrated. [ABSTRACT FROM AUTHOR]

A novel linear non-fluorinated sulfonimide functionalized polyamide (SPA) polymer electrolyte was successfully synthesized via an aromatic sulfonimide monomer with superior thermal stability and superacidity. The aromatic sulfonimide remains stable below 220 °C. To fabricate membranes with strong mechanical strength and dimensional stability, the polymer was blended with various quantities of PVdF. The PVdF/SPA blend membranes exhibit an excellent capacity of water uptake and high dimensional stability. However, their proton conductivity was found to be substantially lower than that of Nafion 211. Analysis on the SEM images of the PVdF/SPA blend membranes reveals that the low proton conductivity is primarily caused by the large pore structures (>1 μm), which lead to breakdown of the continuous proton transport channels. [ABSTRACT FROM AUTHOR]

Abstract: CuO hollow nanospheres with an average diameter of 400nm and shell thickness of 40nm have been successfully synthesized via a simple thermal oxidation strategy with Cu2O solid nanospheres as the precursor. The products have been characterized by X-ray diffraction, transmission electron microscopy and field emission scanning electron microscopy. The formation of CuO hollow nanospheres mainly results from the Kirkendall effect on the basis of temperature-dependent experiments. Furthermore, the electrochemical performance of CuO hollow nanospheres as anode materials for lithium ion batteries has been evaluated by cyclic voltammetry and galvanostatic discharge-charge experiments. The as-prepared CuO hollow nanospheres assembled by nanoparticles exhibit higher initial discharge capacity and better cycle performance than the reported CuO nanoparticles. The hierarchical hollow nanospheres have been demonstrated to take the advantages of nanoparticles and hollow architectures, which could not only shorten the lithium ion transport distance and increase the kinetics of conversion reactions, but also provide suitable electrode/electrolyte contact area and accommodate the volume change associated with lithium ion insertion and extraction. [Copyright &y& Elsevier]

[Display omitted] • P-doped NiS 2 hierarchical architectures with sulfur vacancies are synthesized. • The amounts of P dopants and sulfur vacancies could be precisely controlled. • The optimal catalyst manifests excellent catalytic performance with duriability. • The P dopant activates the electrochemical activities of neighboring Ni and S sites. • The association of P doping with S vacancies tunes the d-band center position. The synergistic achievement of heteroatom doping, defect engineering and appropriate structural design is efficient to adjust and boost the catalytic performance of catalysts yet challenging. Herein, phosphorus (P)-doped NiS 2 hierarchical architectures with sulfur vacancies are synthesized via a Prussian-blue-analogue-sacrificed strategy followed by a phosphidation process. By modulation of P doping and sulfur vacancies, the optimal catalyst manifests outstanding electrocatalytic activities, affording low overpotentials of 73 mV at 10 mA cm−2 for hydrogen evolution reaction (HER), and 255 mV at 20 mA cm−2 for oxygen evolution reaction (OER), respectively. Density functional theory calculations certify that the P dopant not only serves as the new active sites, but also activates the electrochemical activity of neighboring Ni and S sites. Moreover, the synergistic effect of P-doping and sulfur vacancies further improve electrochemical activities of HER and OER by optimizing the adsorption free energy of hydrogen (ΔG H*) and oxygen-containing intermediates (OH*, O* and OOH*), respectively. This finding provides a directive strategy to achieve efficient non-noble metal catalysts for energy conversion and storage. [ABSTRACT FROM AUTHOR]