Wet-chemical Strategy Research Articles

Single-Atom Electron Pumps Over Transition Metal Chalcogenides Boosting Photocatalysis.

Cocatalyst is of paramount significance to provide fruitful active sites for suppressing the spatial charge recombination toward boosted photocatalysis. Up to date, exploration of robust and stable cocatalysts is remained challenging. Inspired by the intrinsic merits of single-atom catalysts (SACs), such as distinctive electronic structure and high atomic utilization efficiency, single-atom/transition metal chalcogenides (TMCs) is utilized as a model to synthesize CdS-Pd single-atom catalyst (CdS-PdSA) heterostructures. This demonstrates the precise anchoring of isolated metal single-atom catalysts (SACs) onto TMCs through a simple yet effective wet-chemical strategy. The resulting heterostructures exhibit significantly enhanced and stable photocatalytic activity for selective anaerobic organic transformations and hydrogen production under visible light. This enhancement is primarily inferred due to the role of Pd SACs as electron pumps, which directionally trap the electrons photoexcited over CdS, accelerating the spatial charge separation and prolonging the carrier lifespan. The charge transport route and photocatalytic mechanism are elucidated. This work underscores the potential of SACs as cocatalysts in heterogeneous photocatalysis, offering valuable insights for the rational design of atomic-level cocatalysts for solar-to-chemical energy conversion and beyond.

Decorated-Induced Oxygen Vacancy Engineering for Ultra-Low Concentration Nonanal Sensing: A Case Study of La-Decorated Bi2O2CO3.

La-decorated Bi2O2CO3 (BCO-La) microspheres are synthesized using a facile wet chemical strategy for sensing low-concentration nonanal (C9H18O) at room temperature. These BCO-La gas sensors are applied to evaluate agricultural product quality, specifically for cooked rice. The sensitivity of the BCO-6La sensor significantly surpassed that of the pure BCO sensor, achieving a response value of 174.6 when detecting 30ppm nonanal gas. Notably, the BCO-6La sensor demonstrated a faster response time (36 s) when exposed to 18ppm of nonanal. Additionally, the selectivity toward nonanal gas detection is higher (approximately 4-24 times) compared to interfering gases (1-octanol, geranyl acetone, linalool, hexanal, 2-pentyfuran, and 1-octen-3-ol) during cooked rice quality detection. The gas sensing mechanism and the factors contributing to the enhanced sensing performance of the BCO-La microspheres are demonstrated through in situ FT-IR spectra and DFT analysis while the realistic detection scenario is carried out. In a broader context, the reported sensors here represent a novel platform for the detection and monitoring of gases released by agricultural products during storage.

In-situ construction of RuS2 nanocrystal-decorated amorphous NiSx nanosheets for industrial-current-density water splitting

Developing enabling electrocatalysts for water splitting to operate at industrial-current-density is crucial for large-scale hydrogen production. Herein, a facile wet-chemistry strategy and scalable in-situ sulfidation technique are designed for formation of RuS2 nanocrystal-decorated amorphous NiSx nanosheets vertically aligned on Ni foam (NF) (RuNiSx/NF) as ultra-highly efficient electrocatalysts for electrochemical water splitting (EWS). The optimized electrocatalyst exhibits an excellent hydrogen evolution reaction (HER) performance, requiring overpotentials of only 15, 50, and 114 mV at 10, 100, and 1000 mA/cm2, respectively, with robust stability at 10, 100, and 500 mA/cm2 for 120 h, ranking it one of the efficient electrocatalysts for industrial water electrolysis. The electron redistribution over heterointerfaces induces the modulatory electronic states of heterostructures, thus leading to the favorable adsorption behavior for reaction intermediates, enhancing intrinsic activity of active sites. Impressively, a RuNiSx/NF||RuNiSx/NF EWS device can afford industrial current densities of 10, 100, and 500 mA/cm2 at voltages of 1.55, 1.77, and 2.35 V, respectively, together with robust durability for over 50 h (@1000 mA/cm2). This work provides an innovative approach to design unique heterostructures for industrial EWS via modulatory electronic states.

Carbon functionalized cladding bismuth tungstate-based 3D twisted micro-flowers for benzaldehyde detection under ultraviolet light excitation

Although semiconducting metal oxide displayed remarkable gas sensing capabilities, their path to commercialization is impeded by several challenges. A primary hurdle is the consistent response of sensing films with impervious feature under diverse detection environment. This report introduces an efficient fabrication technique that yields carbon functionalized cladding bismuth tungstate-based benzaldehyde sensors. The 3D twisted micro-flowers feature was obtained and carbon cladding was uniformly attached by a one-pot wet chemistry strategy. The C0.75/WO3/Bi2WO6 sensor demonstrates superior sensing capabilities for benzaldehyde at a wide range of detection. It features a remarkable sensitivity (33.7 @ 50 ppm), swift recovery time of 49 seconds, enduring stability exceeding 15 days, and robust selectivity, all at a modest room temperature. Even in conditions of high moisture, the response value exhibited minimal degradation, decreasing by a mere 8.96% compared to its performance in the absence of ambient humidity. The complementary density functional theory calculations suggest that the Cx/WO3/Bi2WO6 exhibits a greater benzaldehyde adsorption energy and more robust anti-humidity feature compared to WO3/Bi2WO6, contributing to its enhanced gas-sensing efficacy.

Highly ordered TiO2 Nanotubes decorated with plasmonic silver nanoparticles (TiO2/Ag) for ultra-sensitive SERS detection of textile dye contaminant Rhodamine 6 G

We report a susceptible, ultrafast, molecular fingerprint-specific detection tool of analytes at an extreme trace concentration using surface-enhanced Raman spectroscopy (SERS). Highly ordered TiO2 Nanotubes (NT) modified with plasmonic Ag nanoparticles (Ag) are fabricated by wet chemical strategy. TiO2/Ag nanostructures could benefit the SERS mechanism arising from the effects of both the charge transfer process within TiO2/Ag/analyte and the enhancement in the electromagnetic field by the twining of plasmonic Ag nanoparticles with the construction of semiconductor/plasmonic bi-component system (TiO2/Ag). To achieve a better density of Ag NPs on TiO2 nanotubes, the photoinduction process irradiation time was varied from 10 min to 40 min. The prepared bicomponent SERS system was validated for its structural and morphological properties. SERS optimization studies were analyzed with the probe molecule Rhodamine 6 G (R6G) with an initial concentration of 10−6M. The highest SERS enhancement was notified with TiO2/Ag20 min for R6G sensing. The fabricated optical sensor reproducibility in signal detection was scrutinized with Raman mapping studies and statistically validated by low RSD values of 9.8%. Furthermore, their detectability was gauged with low concentration detection of R6G down to Pico-molar levels (10−12M). Synergistic effects of both CT and EM contributed to SERS enhancement to trace and detected pico-levels of R6G by the fabricated bicomponent semiconductor/ plasmonic heterostructure system (TiO2/Ag 20 min).

Bifunctional PdMoPt trimetallene boosts alcohol-water electrolysis.

Substituting oxygen evolution with alcohol oxidation is crucial for enhancing the cathodic hydrogen evolution reaction (HER) at low voltages. However, the development of high-performance bifunctional catalysts remains a challenge. In this study, an ultrathin and porous PdMoPt trimetallene is developed using a wet-chemical strategy. The synergetic effect between alloying metals regulates the adsorption energy of reaction intermediates, resulting in exceptional activity and stability for the electrooxidation of various alcohols. Specifically, the mass activity of PdMoPt trimetallene toward the electrooxidation of methanol, ethylene glycol, and glycerol reaches 6.13, 5.5, and 4.37 A mgPd+Pt -1, respectively. Moreover, the catalyst demonstrates outstanding HER activity, requiring only a 39 mV overpotential to achieve 10 mA cm-2. By employing PdMoPt trimetallene as both the anode and cathode catalyst, we established an alcohol-water hybrid electrolysis system, significantly reducing the voltage requirements for hydrogen production. This work presents a promising avenue for the development of bifunctional catalysts for energy-efficient hydrogen production.

Diode characteristics, piezo-photocatalytic antibiotic degradation and hydrogen production of Ce3+ doped ZnO nanostructures

Piezo-photocatalysis of ZnO nanostructures had recently well attracted due to their exceptional potential in degrading the antibiotics and scalable hydrogen production. Here, we have synthesized the Ce3+ doped ZnO nanospheres in a facile wet chemical strategy. Dopant ions induced morphological evolution and optical bandgap tuning had observed in our experiment. Optical absorbance spectrum had confirmed the bandgap shortening occurs with Ce3+ doped ZnO specimens. The bandgap gap value had reduced to 2.82 eV from 3.05eV confirming the visible light responsivity of ZnO nano specimens. Obtained Zn(1-x)CexO nanospheres were utilized to fabricate the p-Si/n- Zn(1-x)CexO heterojunction diodes as well studied the improved electrical conductivity for the Ce3+ specimen-based diodes. Besides, ideality factor and barrier height values of the heterojunction diodes ZnO/p-Si, Zn0.99Ce0.01O/p-Si, Zn0.97Ce0.03O/p-Si, and Zn0.95Ce0.05O/p-Si are 15.97 & 0.43 eV, 15.47 & 0.44 eV, 8.02 & 0.46 eV and 5.21 & 0.47 eV, respectively. Direct sunlight assisted piezo-photocatalytic tetracycline (TC) degradation efficiency of ZnO, Zn0.99Ce0.01O, Zn0.97Ce0.03O, and Zn0.95Ce0.05O nanostructures respectively are 64%, 69%, 74% and 82%. We have produced the hydrogen quantity of 1234 μ mol h−1, 1490 μ mol h−1, 1750 μ mol h−1 and 1980 μ mol h−1 with 0%, 1%, 3% and 5% Ce3+ doped ZnO specimens under the direct sunlight assisted piezo-photocatalytic H2 production from H2S splitting.

Two-Dimensional Silver-Metalated Graphdiyne Nanosheets for Photocatalytic Degradation of Antibiotics

The two-dimensional layered carbon allotrope graphdiyne (GDY) is formed by combining hybridized sp–sp2 carbon atoms. This alkynyl-bonded 2D carbon network with tunable energy levels and high carrier-mobility has excellent potential in solar energy utilization. However, the standard but complex synthesis method of GDYs by epitaxial growth on a metal-crystal surface and the poor activity of metal-free materials limit applications beyond the lab. Here, we produce a silver-metalated GDY (Ag-GDY) through a facile and scalable wet-chemistry strategy, featured by an appropriate band gap at 2.61 eV and good e–/h+ separation ability. These unique characteristics facilitate the reaction between Ag-GDY and oxygen to form a variety of active free radicals. The Ag-GDY photocatalyst displays an excellent ability for the light-driven decomposition of antibiotics. Tetracycline with a concentration as low as 5.0 × 10–5 M is degraded within 30 min by Ag-GDY, showing excellent performance stability of up to five reuse cycles.

Stretchable high-entropy alloy nanoflowers enable enhanced alkaline hydrogen evolution catalysis

High-entropy alloys have received much attention in many fields for their unique physicochemical properties, yet precise control at the atomic level in terms of size and morphology remains a great challenge. Herein, we report a kind of stretchable Pt(Co/Ni)MoPdRh HEAs nanoflowers (NFs) assembled by ultra-thin nanosheets (∼ 1.68 nm) for alkaline hydrogen evolution reaction (HER) via one-step wet chemical strategy. The mass activity of HEA NFs reaches 16.64 A mgHEA−1, which is 6.38 times higher than that of commercial Pt/C. The enhanced HER performance and stability is attributed to the multiple active sites in HEAs for reducing the water dissociation energies barriers as well as favoring H adsorption and the strain effect induced by unique structure. This work not only provides a general method for synthesizing unique structures of high entropy alloys, but also provides a fundamental understanding for the study of catalysis in HEAs.

In situ growth of Cu2+1O/Cu2(CO3)(OH)2/Co(OH)2 with multi-dimensional hybrid structure for high performance flexible supercapacitors

In situ growth of Cu2+1O/Cu2(CO3)(OH)2/Co(OH)2 on carbon cloth (CC) is achieved via a facile wet chemical oxidation strategy combined with hydrothermal method, and the self-supported Cu2+1O/Cu2(CO3)(OH)2/Co(OH)2 displays a unique multi-dimensional hybrid structure. Cu2+1O (CuO with excess metal defects) electroless plated on the surface of CC can not only retain the nanostructures of Cu2(CO3)(OH)2 and Co(OH)2, but also act as the buffer layer to ease volumetric expansion of the materials during the repeated charge/discharge process. When the CC@Cu2+1O/Cu2(CO3)(OH)2/Co(OH)2 is used in flexible supercapacitors, it exhibits significantly enhanced areal specific capacitance (624.5 mF cm2 at 0.5 mA cm2), rate capability (86.6 %), cyclic stability (100.3 % retention after 1500 cycles) and coulombic efficiency (99.3 % retention after 1500 cycles) due to the synergistic effect of Cu2+1O buffer layer, two-dimensional (2D) Co(OH)2 nanosheets and three-dimensional (3D) Cu2(CO3)(OH)2 nanoblocks.

Enhanced charge transfer and photocatalytic performance of cube-shaped Ag3PO4@Zeolite-A nanocomposite

Nanostructures that absorb wide range of visible light have the potential ability to combat wastewater problems by acting as visible light active photocatalysts. Ag3PO4 nanostructures are visible light active and can address wastewater problems effectively. The present work explores the visible light activeness of the Ag3PO4 nanostructures for photocatalysis of methylene blue (MB) dye by compositing it with zeolite-A also known as LTA (Linde Type A). Owing to strong adsorption performance and porosity of the LTA, we expect the resulting nanocomposite material to deliver best in the field of adsorption and catalysis. The zeolite-A and Ag3PO4@zeolite-A nanocomposite were synthesized by a facile hydrothermal and wet chemical strategy under normal conditions. The nano-photocatalysts were well characterized for their structural, morphological, compositional, optical, and photocatalytic applications. The structural study revealed the crystalline nature of the composite with the coexistence of the individual phase of Ag3PO4 and the zeolite-A. The morphological investigation depicts the formation of 3D cubical structures having nanoscale dimensions, compositional analysis indicated the purity of the nanostructures consisting of only desired elements. The optical analysis revealed Ag3PO4 as visible light active and zeolite-A as ultraviolet active material. In the case of Ag3PO4@zeolite-A, zeolite provides a large surface area for the adsorption of MB dye, and Ag3PO4 acts as a principal visible light-absorbing material, to catalyze the degradation of MB dye. The composites prepared reduced the chances of charge recombination and inhibit the photo corrosion of the visible light active material Ag3PO4.

Facile wet-chemical fabrication of bi-functional coordination polymer nanosheets for high-performance energy storage and anti-corrosion engineering

Organic materials are of great interest in various applications owing to their intrinsic designability, molecular controllability, ease of synthesis, and ecological sustainability. In this work, a facile and mild wet-chemical strategy was carried out to construct a conjugated Ni-BTA coordination polymer via the π-d hybridization with 1,2,4,5-benzenetetramine (BTA) as π-conjugated ligands and Ni2+ as metallic centers, which exhibits a unique two-dimensional nanosheet-like structure with available active sites, sufficient electrochemical activity, and multi-electron redox capability. On the one hand, the as-prepared Ni-BTA coordination polymer as electrode material exhibits a rapid, reversible, and efficient energy storage behavior with a large reversible capacity of 198 mA·h·g−1 at 1 A·g−1 and a high-rate capability of 150 mA·h·g−1 at 20 A·g−1 in alkali-ion aqueous electrolyte, which are further demonstrated by the in-situ Raman investigation. On the other hand, the Ni-BTA coordination polymer as anti-corrosion additive was introduced into the epoxy resin to achieve a Ni-BTA epoxy coating, which shows a long-term anti-corrosion performance with a low corrosion rate of 4.62 × 10−6 mm·a−1 and a high corrosion inhibition efficiency of 99.86%, suggesting its great engineering potential as the bi-functional organic material for high-performance energy storage and corrosion protection.

Synthesize and tuneable structure, optical, photoluminescence, and magnetic properties of novel SrSnO3/Fe3O4nanocomposites for promising applications

In the current work, a simple wet chemical co-precipitation strategy has been effectively used to synthesize the novel SrSnO3/Fe3O4nanocomposites.The synergistic effect of magnetite on SrSnO3 has been explored by examining the chemical nature of the samples' surfaces, structures, and morphology using XPS, XRD, HRTEM, and FESEM. According to XPS measurements, the Sr2+, Sn4+, Fe2+, 3+, and O states are present in the nanocomposites. XRD reveals nanocomposite oxide materials composed of well-supported nanocrystalline phases from both fundamental oxides. The particles formed were nanocubes, almost round, spherical, tetrahedron, and octahedron-shaped grains, according to HRTEM and SEM analysis. Using UV analysis, the bandgap of a nanocomposite was significantly reduced from 3.7 eV to 2.06 eV.The emission peak has a low intensity, suggesting that there is increased photocatalytic activity in the energetic isolation of electron-hole pairs, which is detected by PL spectroscopy. It was noted that the saturation magnetization values of nanocomposites (8.594, 10.71, 19.13 emu/g) grew with the increase in magnetite content in nanocomposites, which is dominant to other magnetic photocatalysts and indicates enhanced magnetic response which is identified by VSM. This promising nanocomposite could be used in magnetic separation, photocatalysis, and multicolor lighting devices.

Revealing the effect of various organic ligands on the OER activity of MOF-derived 3D hierarchical cobalt oxide @ carbon nanostructures

Intensive research work on the robust and highly active non-precious electrocatalysts for oxygen evolution reactions (OERs) under lenient conditions has been attracted much attention to industrialize water-splitting processes. In this work, we design and develop the cost-effective and highly active Co3O4@C nanostructures derived from two different metal-organic framework (MOF) ligands, including terephthalic acid (PA) and trimesic acid (TMA), through a wet chemical strategy. The unique morphologies (donuts and nanorods over a carbon layer) and excellent surface area of the as-prepared catalysts including Co3O4@C-PA and Co3O4@C-TMA are resulted the increased active centers for OER activity. Among the prepared electrocatalysts, Co3O4@C-TMA exhibits favorable Tafel kinetics (85.18 mV dec−1) and small overpotential (320 mV@10 mA cm−2) for oxygen evolution. In addition to design the effective Co3O4@C electrodes for OER activity, this study also proposes the various multi-functional catalysts for renewable energy conversion applications.

Nickel carbonate Hydroxide-based Core-Triple-Shelled nanofibers with ultrahigh specific capacity for flexible hybrid supercapacitors

Designing novel efficient electrode materials with controlled hierarchical structure and composition for advanced supercapacitors remains a great challenge. Herein, a core-triple-shelled hierarchical GCNF/PANI/NCO nanostructure has been designed and fabricated by sequential growth of the conductive polyaniline (PANI) layers and nickel carbonate hydroxide (Ni2(CO3)(OH)2) nanosheets on the graphene-coated electrospun carbon nanofibers (GCNF) via a facile wet-chemical strategy. Taking full advantage of the free-standing architecture of graphene-coated electrospun carbon nanofibers, high conductivity and flexibility of the PANI layers, and abundant active sites of Ni2(CO3)(OH)2 nanosheets, the optimal GCNF/PANI/NCO (2 h) electrode exhibits a high specific capacitance of 1565F g−1 at 1 A/g and enhanced rate capability, which are higher than those of the GCNF, GCNF/PANI, and GCNF/NCO (2 h) electrodes at the same situation, and also exceeds most of the reported nickel carbonate hydroxide-based electrodes in literature. The superior performance should be mainly ascribed to the collaborative contribution of each component. Moreover, a self-assembled GCNF/PANI/NCO//AC hybrid supercapacitor delivers a high energy density of 35.4 Wh kg−1@750 W kg−1 and a long cycle lifespan. This strategy enables the controllable synthesis of core-triple-shelled hierarchical materials applicable to advanced electrochemical applications.

Porous dehydroxyl cobalt phytate as electrocatalyst for high-efficiency water oxidation

Phytic acid (PA) is a six-fold dihydrogenphosphate ester of inositol with cost-effective, environmentally friendly, and safe properties. Here, we successfully synthesize the dehydroxyl cobalt phytate (PA-Co-400) using PA as phosphorus sources by a one-pot wet-chemistry strategy to prepare the precursor PA-Co and then heat treatment at 400 °C under an N2 atmosphere for dehydroxylation. The average diameter, specific surface area, surface element distribution, and catalytic activity of the catalyst are significantly affected by dehydroxylation temperature. The specific surface area increasesfirstandthendecreases with the treatment temperature from 200 °C to 600 °C. The SEM results indicate that the average diameter of PA-Co-400 particle is 68.90 nm. The as-prepared samples are used as an anode catalyst for electrocatalytic oxygen evolution reaction (OER). The PA-Co-400 exhibits splendid OER performances with an overpotential of 310.31 mV at j10 (η50 = 349.35 mV, η100 = 367.20 mV), which are even comparable to commercial RuO2 (η10 = 310.54 mV, η50 = 389.80 mV, η100 = 450.60 mV). Moreover, the PA-Co-400 has a small Tafel slope of 53.27 mV dec−1, which is lower than commercial RuO2 (81.71 mV dec−1). The ultra-long durability of PA-Co-400 was tested for over 80 h at current densities of 10 mA cm−2 without a significant reduction in 1 M KOH.

Metal Organic Framework-Derived ZnO@GC Nanoarchitecture as an Effective Hydrogen Gas Sensor with Improved Selectivity and Gas Response

Although they are not as favorable as other influential gas sensors, metal-oxide semiconductor-based chemiresistors ensure minimal surface reactivity, restricting their gas selectivity, gas response, and reaction kinetics, particularly when functioning at room temperature (RT). A hybrid design, which includes metal-oxide/carbon nanostructures and passivation with specific gas filtration layers, can address the concerns of surface reactivity. We present a novel hierarchical nanostructured zinc oxide (ZnO), decorated with graphitic carbon (GC) and synthesized via a wet-chemical strategy, which is then followed by the self-assembly of a zeolitic imidazolate framework (ZIF-8). Because of its large surface area, high porosity, and efficient inspection of other analyte (interfering) gases, the ZnO@GC can provide intensified surface reactivity at RT. In the present study, such a hybrid sensor confirmed extraordinary gas sensing properties, which was characterized by excellent H2 selectivity, fast response, rapid recovery kinetics, and high gas response (ΔR/R0 ∼ 124.6%@10 ppm), particularly in extremely humid environments. The results reveal that adsorption sites provided by the ZIF-8 template-based ZnO@GC frameworks facilitate the adsorption and desorption of H2.

Ultrasensitive label-free electrochemical immunosensor of NT-proBNP biomarker based on branched AuPd nanocrystals/N-doped honeycombed porous carbon

N-terminal pro-B-type natriuretic peptide is a major cardiac biomarker for early diagnosis and prognosis of heart failure. Herein, a novel label-free electrochemical immunosensor was developed based on home-made branched AuPd nanocrystals/N-doped porous carbon (AuPd NCS/NPC) for ultrasensitive and high-selective detection of N-terminal pro-B-type natriuretic peptide. Specifically, the AuPd NCS/NPC was prepared by a one-pot wet-chemical strategy by using thymine as a green structural directing agent, whose morphology, structures, and properties were strictly examined, showing high-efficiency catalysis towards electro-reduction of hydrogen peroxide. Under the optimized conditions, the fabricated sensor exhibited a dynamic linear range of 0.001 ∼ 10 ng mL−1 and a low limit of detection (0.34 pg mL−1, S/N = 3) for immunoassay of N-terminal pro-B-type natriuretic peptide. Furthermore, this platform was explored for detection of the biomarker in human serum sample with satisfactory results. Thus, the built biosensor can render valuable guidance for prospective clinical diagnostic applications.

A facile and low-cost wet-chemistry artificial interface engineering for garnet-based solid-state Li metal batteries

Solid-state lithium metal batteries (SSLMBs) have been widely predicted as an “enabler” for the next-generation high-energy-density batteries. To perform this goal, both solid electrolytes (SEs) and metallic Li anodes are the keys. Li-rich garnet SEs exhibit many unique advantages for enabling SSLMBs, such as high Li-ion conductivity, superior mechanical, chemical and electrochemical properties. However, the garnet-based SSLMBs suffer from intractable interfacial problems including poor-contact-induced high interfacial impedance and dendrite-induced fast short circuit, which greatly hinder their practical application. In this work, a facile and low-cost artificial interface engineering is proposed to improve Li/SEs interface. Benefitted from the superior wettability of isopropanol InCl3 solution on the Li6.4La3Zr1.4Ta0.6O12 (LLZTO) surface, a homogeneous and tightly-adhering lithiophilic interface consisting of InLix and LiCl is efficiently constructed. As a result, the interface impedance was decreased from 189 to 10 Ω, and the critical current density for the LLZTO is increased from 0.2 mA cm−2 to 0.7 mA cm−2. The Li/Li symmetric cells can work stably above 4000 h at a current density of 0.2 mA cm−2. At a higher current density of 0.45 mA cm−2, no obvious dendritic Li proliferation and interfacial contact failure is observed after cycling for more than 1000 h. The full cells with LiFePO4 as cathode exhibit a superior electrochemical performance with a reversible capacity of 127 mAh g−1 at 0.5 C after 475 cycles, and a rate capability of 101 mAh g−1 at 1 C. This effective, simple and economical wet-chemistry strategy for constructing Li/SEs artificial interface may provide an alternative route for solve the interfacial issues of other SSLMBs.

Toroidal dipole-modulated dipole-dipole double-resonance in colloidal gold rod-cup nanocrystals for improved SERS and second-harmonic generation.

Colloidal metal nanocrystals (NCs) show great potential in plasmon-enhanced spectroscopy owing to their attractive and structure-depended plasmonic properties. Herein, unique Au rod-cup NCs, where Au nanocups are embedded on the one or two ends of Au nanorods (NRs), are successfully prepared for the first time via a controllable wet-chemistry strategy. The Au rod-cup NCs possess multiple plasmon modes including transverse and longitudinal electric dipole (TED and LED), magnetic dipole (MD), and toroidal dipole (TD) modulated LED resonances, producing large extinction cross-section and huge near-field enhancements for plasmon-enhanced spectroscopy. Particularly, Au rod-cup NCs with two embedded cups show excellent surface-enhanced Raman spectroscopy (SERS) performance than Au NRs (75.6-fold enhancement excited at 633 nm) on detecting crystal violet owing to the strong electromagnetic hotspots synergistically induced by MD, LED, and TED-based plasmon coupling between Au cup and rod. Moreover, the strong TD-modulated dipole-dipole double-resonance and MD modes in Au rod-cup NCs bring a 37.3-fold enhancement of second-harmonic generation intensity compared with bare Au NRs, because they can efficiently harvest photoenergy at fundamental frequency and generate large near-field enhancements at second-harmonic wavelength. These findings provide a strategy for designing optical nanoantennas for plasmon-enhanced applications based on multiple plasmon modes.Electronic Supplementary MaterialSupplementary material (SEM image of Au rod-one-cup NCs; TEM image of Au/PbS hybrids; SEM image of Au rod-two-cup NCs; low-amplification SEM image of Au rod-two-cup NCs; experimental extinction and calculated electric field distributions of Au NR excited at different wavelengths; calculated absorption and scattering spectra of Au rod-one-cup NCs; schematic illustration of the cut plane and the corresponding magnetic field distribution under L3 excitation; Raman spectra of CV (10−6 M) adsorbed on Au rod-cup NCs with different cup sizes; calculated magnetic field distribution of Au rodcup NCs excited at 532 and 633 nm; calculated electric field distributions of Au rod-one-cup NC excited at 600 nm along TE and LE; the models of Au rod-cup NCs used in the simulations) is available in the online version of this article at 10.1007/s12274-022-4562-5.