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The potential of zinc metal anodes (ZMAs) for use in emerging aqueous electrochemical devices like rechargeable zinc-ion batteries and hybrid capacitors is substantial, owing to their high theoretical capacity, low redox potential, non-toxicity, abundant availability, and cost-effectiveness. However, the practical application of ZMAs faces limitations due to issues such as uncontrolled zinc dendrite growth and side reactions. In this study, we demonstrate that simultaneously incorporating scandium ions (Sc3+) and acetate anions (Ac−) as electrolyte additives into a common ZnSO4 solution significantly enhances the cycling stability and reversibility of ZMAs. Our findings reveal that the Ac− acts as a pH regulator, dynamically buffering the electrolyte pH to be around 4.3, effectively suppressing water-induced side reactions. Additionally, the synergistic effect of Sc3+ and Ac− (Sc3+/Ac−) facilitates the desolation process of Zn2+ and lowers the energy barrier for electrochemical Zn plating, resulting in uniform Zn plating without noticeable zinc dendrite growth. Consequently, Zn‖Zn symmetric cells utilizing the Sc3+/Ac− electrolyte additive exhibit an ultra-long lifespan exceeding 1000 hours at 2.0 mA cm−2 and 1.0 mA h cm−2. Moreover, the Zn‖Cu cell demonstrates a high average coulombic efficiency of 99.4% after 400 plating/stripping cycles at 1.0 mA cm−2 and 1.0 mA h cm−2. Notably, when paired with an activated carbon (AC) cathode, Zn‖AC hybrid capacitors maintain a high-specific capacity of 62 mA h g−1 after 10 000 cycles at 1.0 A g−1. The research outcomes indicate that Sc3+ in combination with Ac− are promising electrolyte additives for achieving highly stable aqueous ZMAs. [ABSTRACT FROM AUTHOR]

Trace Sc3+ additive (1.0 mol%) is shown to greatly improve the Coulombic efficiency and cycling stability of Zn metal anodes in aqueous ZnSO4 electrolyte due to the decreased nucleation overpotential and increased kinetics for Zn plating/stripping. Both Zn‖Zn and Zn‖V2O5 cells show enhanced cycling stability and rate capability in the Sc3+-modified electrolyte. [ABSTRACT FROM AUTHOR]

Improving the intrinsic Na+ ion diffusivity of the advanced cathode material Na3V2(PO4)2O2F (NVPOF) has been a fundamental strategy to enhance its Na+ ion storage performance, while challenges remain in structural design and fabrication with specific features targeting the alleviation of migration energy barriers of the Na+ ions at different (de)sodiated states. Herein, K+ ions are introduced into the Na-sites in NVPOF to create Na+ ion vacancies, support the Na+ ion transport channels in the c axis and disrupt the continuity of the crystal structure. This strategy simultaneously reduces the electrostatic repulsive forces on the migrating Na+ ions from neighboring Na+ ions at a sodiated state and energy barriers originating from Na+ ion ordering at a desodiated state. Thus, the obtained NVPOF-K0.05 cathode presents a dramatic enhancement in the rate capability up to 80C (49.1 mA h g−1) and almost no decay in the long cycles at 10C up to 500 cycles (106.7 mA h g−1). The NVPOF-K0.05//Se@C sodium-ion full cell exhibits outstanding energy/power density (430.3 W h kg−1 at 208.3 W kg−1 and 310.5 W h kg−1 at 3357.1 W kg−1) and cycling stability (86.5% capacity retention of 107.1 mA h g−1 after 1000 cycles at 10C). [ABSTRACT FROM AUTHOR]

Restacking of 2D nanomaterials is often deemed to be detrimental to their applications. In contrast to this common notion, here we demonstrate that tightly packed stacked MoS2 exhibits a higher electrocatalytic activity for hydrogen evolution than the more loosely stacked ones. [ABSTRACT FROM AUTHOR]

The progress of two-dimensional (2D) MXene-derived QDs (MQDs) is in the early stages, but the materials have aroused great interest due to their high electrical conductivity, abundant active catalytic sites, easily tunable structure, satisfactory dispersibility, remarkable optical properties, good biocompatibility, manifold functionalizations, and so on. However, up to now, there is still no review paper on MQDs. Herein, the research advances of MQDs, including their synthetic routes (top-down and bottom-up methods), properties (structural, electronic, optical and magnetic properties), functionalizations (surface modifications, heteroatom doping and the construction of composites) and applications (sensing, biomedical, catalysis, energy storage and optoelectronic devices etc.), are critically highlighted, and the future prospects and challenges of MQDs are discussed. This review will serve as a one-stop point for comprehending the most advanced developments of MQDs, and will hopefully enlighten researchers to employ MQDs for satisfying the growing requirements of the diverse applications. [ABSTRACT FROM AUTHOR]

Solar energy is a clean and sustainable energy source. Natural photosynthesis has existed for millions of years, which can convert solar energy into chemical energy needed by living things. Inspired by natural photosynthesis, scientists have developed a series of artificial photosynthetic systems that can use solar energy efficiently for humans. Conjugated microporous polymers (CMPs) are a new class of materials that can be used in artificial photosynthetic systems. This review illustrates the light-harvesting capability and the energy transfer phenomena within the supramolecular structure of CMPs to provide guidelines for the rational design of these polymers with excellent photocatalytic properties and systematically discusses the applications of these materials in the field of photocatalysis including photocatalytic water splitting, CO2 reduction, organic conversion, environmental remediation, and medical health. Finally, this review points out the major challenges in this topic and suggests the next feasible development direction. [ABSTRACT FROM AUTHOR]

Metal-free black phosphorus (BP) nanosheets have emerged as a promising photocatalyst. Herein, early transition-metal carbide and nitride (MXene) decorated BP (Ti3C2Tx/TiO2–BP) nanohybrids were constructed by a hydrothermal method, in which TiO2 was produced in the hydrothermal process. The optimized Ti3C2Tx/TiO2–BP nanohybrids exhibited a higher visible-light photodegradation efficiency of rhodamine B (99.09%) and tetracycline hydrochloride (92.70%) pollutants than that of pristine BP (12.75% and 9.35%, respectively). Diverse characterization techniques and density functional theory calculations have revealed that such enhanced photocatalytic performance was due to the synergistic effect of BP and Ti3C2Tx/TiO2, which could markedly improve the stability of BP, increase visible light absorption, prolong the photoexcited electron lifetime, accelerate the photoinduced electron transfer and hinder the electron–hole (e−–h+) pair recombination. Meanwhile, the mechanism analysis indicated that ˙O2− radicals played a leading role in the photocatalytic process. This study will motivate great interest in using 2D MXenes as co-catalysts to enhance the activity of BP for its applications. [ABSTRACT FROM AUTHOR]

In past decades, with interest in wearable smart devices rapidly growing, the design and fabrication of novel energy storage devices have received increasing attention. Although secondary batteries are among the best options in this area, their bulky construction remains unable to fulfil the specific demands of miniaturization, portability, and flexibility. This review comprises a brief update on recent progress in printable secondary batteries, in combination with their principles and frequently used printing techniques. Moreover, we also discuss the challenges and advantages of printed secondary batteries and describe their future prospects in wearable smart devices. [ABSTRACT FROM AUTHOR]

A supercapacitor that possesses excellent performance in a wide temperature range is constructed with a partially graphitized porous carbon (PGPC) as the electrode material and tetraethylammonium tetrafluoroborate/propylene carbonate (Et4NBF4/PC) as the electrolyte. The PGPC-based electrode shows a very consistent performance in a wide temperature range of −20 to 50 °C. At working temperatures as high as 50 °C and as low as −20 °C, it delivers specific capacitances of ∼148 and ∼135 F g−1, respectively, and the supercapacitors exhibit high energy densities of ∼46 and ∼43 W h kg−1. In particular, the low-temperature capacitive performance and rate capability of PGPC are much better than those of the normally used activated carbon and among the best ones ever-reported for carbon-based supercapacitors. More significantly, the PGPC-based supercapacitor shows excellent cycling performance at all tested working temperatures, with a capacitance retention of ∼98% after 1000 cycles at 5 A g−1 even when the working temperature decreases to −20 °C. [ABSTRACT FROM AUTHOR]

Magnesium citrate and potassium citrate are two commonly used food additives in our daily life. Herein, we prepared nitrogen-doped hierarchical porous carbon nanosheets (N-HPCNSs) through direct pyrolysis of their mixtures and subsequent NH3 treatment. The as-prepared N-HPCNS shows hierarchical porosity (specific surface area of 1735 m2 g−1 and pore volume of 1.71 cm3 g−1), and a moderate nitrogen doping of 1.7%. Moreover, it can be effectively applied in various energy storage/conversion systems. When used as supercapacitor electrodes, it shows a high specific capacitance of 128 F g−1 in organic electrolytes and retains 45% of the original capacitance even at an ultrahigh current density of 100 A g−1. It can also serve as an effective sulfur carrier in lithium–sulfur batteries. The N-HPCNS/sulfur cathode shows high discharge capacities of 1209 mA h g−1 at 0.2C and 493 mA h g−1 even at 4C. Over 500 charge/discharge cycles at 1C, it still retains a high discharge capacity of 486 mA h g−1 with an ultralow capacity loss of 0.051% per cycle and a high average coulombic efficiency of 99.4%. [ABSTRACT FROM AUTHOR]

Trace Sc 3+ additive (1.0 mol%) is shown to greatly improve the Coulombic efficiency and cycling stability of Zn metal anodes in aqueous ZnSO 4 electrolyte due to the decreased nucleation overpotential and increased kinetics for Zn plating/stripping. Both Zn‖Zn and Zn‖V 2 O 5 cells show enhanced cycling stability and rate capability in the Sc 3+ -modified electrolyte.

Restacking of 2D nanomaterials is often deemed to be detrimental to their applications. In contrast to this common notion, here we demonstrate that tightly packed stacked MoS2 exhibits a higher electrocatalytic activity for hydrogen evolution than the more loosely stacked ones.

Electrospun carbon fiber films have high contact resistance at the fiber junctions, which causes poor cycling stability and limits their further improvement in energy storage performances. To eliminate the contact resistance of the film, we provide a new strategy to fuse the fiber junctions by introducing MoO 2 in the fibers, which replaces the C-C interface by a more active C-MoO 2 -C interface at the fiber junction to promote mass transfer. MoO 2 reacts with C matrix to generate Mo 2 C and form self-fused junctions during the carbonization process. Due to much lower charge transfer and sodium diffusion resistance, the C-Mo 2 C fiber film with self-fused junctions shows much better cyclability with capacity retention of 90% after 2000 cycles at a constant current density of 1 A g -1 . Moreover, the Mo 2 C particles provide many electrochemically active sites, leading to additional improvement in sodium storage. The C-Mo 2 C fiber film has a capacity of 134 mA h g -1 at 1 A g -1 and a high capacity of 99 mA h g -1 even at 5 A g -1 ., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Graphene oxide (GO)-Ag(3)PO(4) nanocomposites synthesized through a facile solution approach via electrostatic interaction were investigated as excellent photocatalysts for the degradation of rhodamine B (RhB) under visible light irradiation. SEM and TEM observations indicate that Ag(3)PO(4) nanospheres of ~120 nm in diameter were well dispersed and anchored onto the exfoliated GO sheets. The characterizations of FTIR and Raman demonstrated the existence of strong charge interactions between GO sheets and Ag(3)PO(4) nanospheres. As compared to Ag(3)PO(4) nanospheres alone, the attachments of GO sheets led to a band gap narrowing (2.10 eV) and a strong absorbance in the near infrared region (NIR). The photoluminescence (PL) analysis indicates a more efficient separation of electron-hole pairs in the GO-Ag(3)PO(4) nanocomposites. Notably, the incorporation of GO sheets not only significantly enhances the photocatalytic activity but also improves the structural stability of Ag(3)PO(4). The positive synergistic effects between Ag(3)PO(4) nanospheres and GO sheets are proposed to contribute to the improved photocatalytic properties. A possible photocatalytic mechanism of the GO-Ag(3)PO(4) nanocomposites was assumed as well. The integration of these advantages enables such GO-Ag(3)PO(4) hybrid material to be a nice photocatalyst for broad applications in a sewage treatment system.