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Carbon neutrality is a fundamental strategy for achieving the sustainable development of human society. Catalyzing CO₂ reduction into various high-value-added fuels serves as an effective pathway to achieve this strategic objective. Atom-dispersed catalysts have received extensive attention due to their maximum atomic utilization, high catalytic selectivity, and exceptional catalytic performance. Dual-atom catalysts (DACs), as an extension of single-atom catalysts (SACs), not only retain the advantages of SACs, but also produce many new properties. This review initiates its exploration by elucidating the mechanism of CO₂ reduction reaction (CO₂RR) from CO₂ adsorption and CO₂ activation. Then, a comprehensive summary of recently developed preparation methods of DACs is presented. Importantly, the mechanisms underlying the promoted catalytic performance of DACs in comparison to SACs are subjected to a comprehensive analysis from adjustable adsorption capacity, tunable electronic structure, strong synergistic effect, and enhanced spacing effect, elucidating their respective superiorities in CO₂RR. Subsequently, the application of DACs in CO₂RR is discussed in detail. Conclusively, the prospective trajectories and inherent challenges of CO₂RR are expounded upon concerning the continued advancement of DACs. This thorough review not only enhances the comprehension of DACs within CO₂RR but also accentuates the prospective developments in the design of sophisticated catalytic materials.

Water electrolyzer is crucial for producing clean hydrogen, but the traditional approach faces challenges owing to the oxygen evolution reaction (OER) slow kinetics at the anode. Hybrid water splitting replaces the OER with the oxidation of an organic molecule to enhance hydrogen production along with value-added products. The scarcity of affordable and highly effective catalysts remains a major challenge. MXene, a 2D nanomaterial, has gained substantial attention for its enviable properties, for instance high conductivity, hydrophilicity, and substantial surface area. This review discusses experimental methods for synthesizing MXene and MXene-based nanocomposites. Furthermore, the small molecules oxidation such as benzyl alcohol, methanol, ethanol, urea, hydrazine, furfural, and formic acid as alternatives to the oxygen evolution reaction is examined. Finally, an understanding of imminent research and the development of MXene-associated materials in electrocatalytic applications are presented.

In this work, it is reported a scalable and systematic protocol for the preparation of xerogels based on the use of green, highly available, and low-cost materials, i.e. halloysite nanoclay and chitosan, without the need for any expensive equipment or operational/energetic demands. Starting from colloidal dispersions, rheological studies demonstrate the formation of hydrogels with zero-shear viscosities enhanced by ≈9 orders of magnitude and higher storage moduli. Hence, the corresponding self-standing xerogels are prepared by a simple solvent casting method and their properties depend on the concentration of halloysite, possessing enhanced thermal stability and outstanding mechanical performances (elastic modulus and ultimate elongation of 165 MPa and 43%, respectively). The resulting biohybrid materials can be exploited for environmental remediation. High removal efficiencies are reached for the capture of organic molecules from aqueous media and the CO₂ capture from the atmosphere is also investigated. Most importantly, the presence of an inorganic skeleton within the xerogels prevents the structure from collapsing upon drying and it allows for the control over their morphology and shape. Therefore, taking advantage of the overall features, the designed xerogels offer an attractive strategy for sustainably tackling pollution and for environmental remediation in a plethora of different domains.

Herein, the emission characteristics of diammonium N,N,N',N'-tetramethyl-1,4-phenylenediammonium (TMPDA) are investigated based on lead iodide (TMPDA)PbI₄ perovskite single crystals correlated with the localized lattice vibrations. Dual emission characteristics are ascribed to the existence of free exciton and bound exciton. The photoluminescence spectra as a function of excitation power and temperature show that structural distortion and exciton-phonon coupling impact emission characteristics substantially. The coupling strength between excitons and phonons in (TMPDA)PbI₄ is estimated as γ_ac = 308.96 µeV and γ_LO = 62.3 meV, which is much higher than inorganic semiconductors. Further, bound exciton band recombination is significantly suppressed at lower temperatures due to increased localization of carriers. Specific heat deviation from the Dulong-Petit law indicates strong coupling in the lattice. The Debye-Einstein model reveals multiple low-energy localized independent vibrations, leading to phonon coupling with bound excitons. This interplay, along with Bosonic features, significantly influences emission properties. Further, it is observed that photocurrent as a function of the incident intensity follows a law ∝ I₀ ^α with α = 0.54, attributed to substantial bimolecular recombination of carriers. The findings of the study provide an in-depth understanding of emission characteristics, lattice distortion, and interplay of electron-phonon coupling in DJ phase 2D perovskite system.

When the diameter of semiconductor nanowires is below the Bohr radius, confined excitons in the radial direction can freely move along the elongated axis direction, highlighting their potential for applications in quantum information and optoelectronic devices. Controlled anisotropic growth and oriented attachment are viable strategies for producing ultra-long semiconductor nanowires with precisely controlled lengths and diameters. Anisotropic ZnSe nanorods are used as the initial seeds for the controlled anisotropic growth and oriented attachment methods. ZnSe nanorods/nanowires with limiting lengths of tens to hundreds of nanometers are produced. The advantages and limitations of semiconductor nanowires via controlled anisotropic growth and oriented attachment are summarized. The perspective for the promotion of controlled anisotropic growth and oriented attachment is discussed, which allows to promotion of the precise synthesis of semiconductor ultra-long nanowires to develop the fundamental research and applications of ultra-long semiconductor nanowires.

The dissolution and shuttle of lithium polysulfides (LiPSs) should be primarily responsible for rapid capacity decay in lithium-sulfur batteries (LSBs), which severely limits sulfur utilization. Introduction of cathode additives that can immobilize and rapidly convert LiPSs has been identified as effective in alleviating the shuttle effect. In this study, N/S codoped carbon dots (NSCDs) have been synthesized via a typical hydrothermal method, whose surfaces are rich in polar functional groups (─COOH, ─OH, ─SO_3, and ─NH₂) to capture LiPSs and effectively modulate the deposition behavior of Li₂S. NSCDs as an additive of cathode significantly improve the battery discharge capacity and cycle life that it could deliver a reversible specific capacity of 1207.2 mAh g^-1 at a current density of 0.2 C and stably operate for over 400 cycles at 1 and 2 C current densities. This work provides valuable insights into the application of 0D carbon nanomaterials in the field of LSBs.

Deconvoluting the vibrations and harmonics in solid-solid interfaces is crucial for designing materials with improved performance, durability, and functionality. The measured vibrating microcantilever signal in the dynamic atomic force microscopy (AFM) encompasses a multitude of distinct signatures reflecting a diverse array of material properties. Nevertheless, uncertainties persist in decoding these signatures, primarily arising from the interplay between attractive and repulsive forces. Consequently, it is challenging to correlate the generated harmonics within the solid-solid interfaces with the imaged phase and topography of materials, as well as the occasional observed contrast reversal. In this study, the vibration harmonics produced at solid-solid interfaces are correlated, linking them to short-range nano-mechanical characteristics through a comprehensive blend of theory, simulation, and experimental methods. These findings shed light on the roots of harmonic generation and contrast reversals, opening avenues for designing innovative materials with customized properties.

The success of gene therapy hinges on the effective encapsulation, protection, and compression of genes. These processes deliver therapeutic genes into designated cells for genetic repair, cellular behavior modification, or therapeutic effect induction. However, quantifying the encapsulation efficiency of small molecules of interest like DNA or RNA into delivery carriers remains challenging. This work shows how super-resolution microscopy, specifically direct stochastic optical reconstruction microscopy (dSTORM), can be employed to visualize and measure the quantity of DNA entering a single carrier. Utilizing pNIPAM/bPEI microgels as model nano-carriers to form polyplexes, DNA entry into the carrier is revealed across different charge ratios at temperatures below and above the volume phase transition of the microgel core. The encapsulation efficiency also depends on DNA length and shape. This work demonstrates the uptake of the carrier entity by primary derived macro-phages and showcases the cell viability of the polyplexes. The study shows that dSTORM is a potent tool for fine-tuning and creating polyplex microgel carrier systems with precise size, shape, and loading capacity at the individual particle level. This advancement shall contribute significantly to optimizing gene delivery systems.

Adjusting the hole transport layer (HTL) to optimize its interface with perovskite is crucial for minimizing interface recombination, enhancing carrier extraction, and achieving efficient and stable inverted perovskite solar cells (PSCs). However, as a commonly used HTL, the self-assemble layer (SAM) of [2-(3,6-dimethoxy-9H-carbazol-9-yl)ethyl] phosphonic acid (MeO-2PACz) tends to form clusters and micelles during the deposition process, leading to inadequate coverage of the ITO substrate. Here, a Co-SAM strategy is employed by incorporating 4-mercaptobenzoic acid (SBA) and 4-trifluoromethyl benzoic acid (TBA) as additives into MeO-2PACz to fabricate a Co-SAM-based HTL. The introduced additive can interact with MeO-2PACz, facilitating cluster dispersion and thereby enabling better deposition on ITO for improved HTL coverage. Moreover, Co-SAM exhibits superior energy level alignment with perovskite to enhance interfacial contact and improve carrier extraction efficiency as well as promote growth of bottom perovskite grains. As a result, an impressive increase of the power conversion efficiency (PCE) from 21.34% to 23.31% is achieved in the inverted device based on the Co-SAM HTL of MeO-2PACz+TBA while maintaining ≈90% of its initial efficiency under continuous operation at 1-sun.

Circularly polarized luminescence (CPL) plays a crucial role in the fields of optical display and information technology. The pursuit of high dissymmetry factors (g_lum) and fluorescence quantum yields in CPL materials remains challenging due to inherent trade-offs. In this work, molecular imprinting technology is employed to develop novel CPL-active polymer films based entirely on achiral fluorene-based polymers, achieving an enhanced g_lum value exceeding 4.2 × 10^-2 alongside high quantum yields. These chiral molecularly imprinted polymer films (MIPF) are synthesized via a systematic three-step process: co-assembly with limonene and a porphyrin derivative (TBPP), interchain crosslinking, and subsequent removal of small molecules. During this process, limonene acts as the chiral inducer, while TBPP serves dual roles as both the chiral enhancer and imprinted molecule. The elimination of TBPP creates chiral sites for various fluorescent molecules, facilitating full-color CPL emission. The chiral MIPF exhibits stable CPL performance even after multiple cycles of post-assembly and removal. Furthermore, these films can function as interfacial microreactors, enabling in situ chemical reactions that dynamically regulate CPL signals. Additionally, chiral self-organization within achiral azobenzene polymer films can also be achieved using MIPF, serving as intense chiral light sources.