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In this research, we present an innovative, environmentally friendly, and cost-effective alcohothermal method for synthesizing Mn2+ and Mn2+–Cu+ doped 0D Cs3ZnCl5, a green luminescent material, marking the first time this approach has been reported. An exhaustive analysis of the luminescence properties of both undoped and doped Cs3ZnCl5 was conducted, with a particular emphasis on the energy transfer mechanisms in the Mn2+ mono-doped and Mn2+–Cu+ co-doped systems. The results demonstrate the successful construction of an efficient energy transfer pathway that significantly enhances the luminescence efficiency of Cs3ZnCl5:Mn2+. Specifically, the photoluminescence quantum yield of Mn2+ within the Cs3ZnCl5 matrix has been improved from 51.6% to 71.1%, thanks to the Cu+ codopant acting as an effective energy transfer mediator. A mechanism for the luminescence and energy transfer phenomena observed in the Mn2+–Cu+ co-doped Cs3ZnCl5 system has been also proposed. Furthermore, to assess the practical applicability of the synthesized materials, their structural and photoluminescent stability were evaluated. In essence, our study presents a promising solution to current challenges in the synthesis of advanced luminescent materials and opens up new possibilities for harnessing the potential of Mn2+-activated 0D metal halides in optoelectronic applications. [ABSTRACT FROM AUTHOR]

Stimulus-responsive materials provide an attractive platform to design and build distinguished soft robots that can dynamically change their shapes to adapt for a variety of functions. However, in most cases, soft robots mainly rely on delicately and laboriously tailoring material composition and molecular orientations to achieve desirable shape morphing. Moreover, the integration of multimodal shape morphing into a single robot, control of the evolution between different morphing modes, complex locomotion, and facile fabrication represent major challenges in this area. Here, we show a facile strategy to photomanipulate shape morphing of a soft millirobot made of an NIR-active liquid crystal elastomer by programming the direction and magnitude of strain gradient in the LCE by using the spatial and localized features of light stimuli. This photomanipulation strategy not only enables the millirobot to generate a wide range of morphing modes, but also allows local and reversible evolution between different morphing modes in a single soft robot. With these phototunable morphing capabilities, the millirobot is able to exert multimodal locomotive behaviors, including crawling, shifting, rotating, somersaulting, rolling, and even fast autonomous rocking driven by a self-oscillatory motion. In addition, the highly mobile millirobots show the multifunctions of not only navigating with controllable directions but also escaping out from heavy weight and even swimming through a small pipe. It is anticipated that this photoactive and reconfigurable material system would open exciting possibilities to develop intelligent soft robots with seamless integration of multimodal shape morphing and multifunctions. [ABSTRACT FROM AUTHOR]

Exploring cost-effective electrodes operating at a high current density above 400 mA cm−2 is still challenging for the industrial application of water splitting. Herein, the corrosion layers of iron foam are tailored towards preparing self-supporting electrodes for the oxygen evolution reaction (OER). Corrosion reactants (Ni2+, O2 and H2O) are adopted to regulate the structures and electrochemical performances of electrodes on account of the diverse iron corrosion behaviors. By further comparing the spontaneous iron corrosion in ZnCl2, CoCl2, NiCl2 and FeCl3 solutions, it is identified that the appropriate electrode potentials of Ni/Ni2+ and Co/Co2+ are favourable for achieving uniformly ordered corrosion layers owing to the simultaneously occurring oxygen corrosion and replacement reaction. The as-prepared electrode exhibits excellent OER performances of affording low overpotentials of 221 and 291 mV to reach 100 and 500 mA cm−2, respectively, as well as steadily operating at 500 mA cm−2 for 100 h. Integrating with a prominent hydrogen evolution reaction (HER) catalyst, an industrially required current density of 500 mA cm−2 has been obtained at 1.81 V. Importantly, a large-area electrode (8 × 8 cm2) has been successfully prepared. This work establishes potential possibilities for designing inexpensive and efficient electrocatalysts through regulated metal corrosion. [ABSTRACT FROM AUTHOR]

Electrocatalytic water splitting to produce clean and sustainable hydrogen energy is regarded as a promising strategy to address the growing energy and environmental problems. Thus, the search for low-cost and efficient electrocatalysts plays a vital role in water electrolysis. In recent years, metal alkoxides, which are a series of organic–inorganic hybrid compounds, have attracted tremendous attention in energy research owing to their appealing features of high porosity, large surface area, adjustable composition and regulated hierarchical structures. However, the development of metal alkoxides towards electrocatalysis has not been established systematically. Herein, we review and discuss the recent advances on metal alkoxides and their derivatives (including hydroxides, oxides, phosphides, sulfides, and selenides) for electrocatalytic water splitting. The fundamental principles of how to regulate their composition, phases and hierarchical structures to enhance their performance are highlighted, also including their correlative structure–activity relationship. Finally, the issues and future challenges with the use of metal alkoxide-based nanomaterials for electrocatalytic applications are proposed. This review aims to present a comprehensive understanding of metal alkoxide-based electrocatalysts and some suggestions for the future development of high-performance electrocatalysts for water splitting applications. [ABSTRACT FROM AUTHOR]

Exploring highly efficient and cost-effective electrocatalysts for the oxygen evolution reaction (OER) is becoming increasingly important in the field of sustainable energy systems. In this work, a three dimensional (3D) hierarchical porous nickel and iron based sulfide (Ni–Fe–S) with a sea urchin-like morphology is synthesized by a facile sulfurization of Prussian blue analogue (PBA) precursors with a hydrothermal reaction and post-calcination treatment. The mass ratio of PBA and sulfur sources, the hydrothermal temperature and time, and the presence of hydrazine hydrate are found to be important factors for the formation of the unique sea urchin-like materials with the porous carbon layer and mixed phases of Fe5Ni4S8 and NiS, which are conducive to fast mass and charge transfer along various directions, endow the materials with mixed valences, improve the electronic conductivity and prevent the agglomeration of nanostructured sulfides. Benefiting from these fascinating advantages, the optimal Ni–Fe–S catalyst exhibits excellent catalytic activities with an overpotential as low as 200 mV to attain a current density of 10 mA cm−2 and good stability toward the OER. This work not only offers a facile strategy to prepare efficient transition metal based sulfides with excellent electrocatalytic activity for the OER but also extends the synthesis and application of PBA-derived nanostructured materials. [ABSTRACT FROM AUTHOR]

Tuning the hydrogen adsorption energy (EH) by controlling the surface electronic structure of Pt is essential for enhancing the hydrogen oxidation reaction (HOR) performance in alkaline media. This could be achieved by forming a Pt skin on PdFe/C nanoparticles with structurally ordered intermetallic (O-PdFe@Pt/C) or disordered alloy (D-PdFe@Pt/C). The HOR activity on O-PdFe@Pt/C exhibits an exchange current density of 1.49 A mgPt−1, which is 3.87 and 7.56 times higher than that on D-PdFe@Pt/C (0.385 A mgPt−1) and Pt/C (0.197 A mgPt−1), respectively. The excellent electrocatalytic HOR performance on O-PdFe@Pt/C can be ascribed to the attenuation of EH on the Pt shell induced by the structurally ordered PdFe core, where the EH on O-PdFe@Pt surface is 0.18 eV smaller than that on Pt according to DFT calculations. [ABSTRACT FROM AUTHOR]