ACS Applied Energy Materials最新文献

Electrochromic (EC) technology, with its reversible color changes and special light modulation, has a wide range of applications in adaptive military camouflage. However, there are still some problems such as difficulties with multicolor display, flexible patterned displays, and difficult integration with electrochromic and energy storage that limit its development and applications in portable military camouflage devices. In this work, a multicolored conjugated polymer, p3DT-FSQ, was designed and prepared by electrochemical polymerization. The polymer film exhibits a reversible color change, high optical contrast, and a fast switching time. On this basis, the reflective and transmissive zinc-based electrochromic devices (RZECD and TZECD) were optimally assembled based on the p3DT-FSQ film as the EC layer and zinc sheet or zinc frame as the counter electrode. Both RZECD and TZECD show reversible orange-yellow, earthy yellow, and army green colors at various potentials with good energy storage properties and excellent flexibility, meeting the demand for color variation and functionality in modern electronic combat environments. It is even more intriguing that the patterned TZECDs can accurately simulate six combat environments, including Gobi, highland, wilderness, cropland, desert, and forest. This work presents a design strategy for an adaptive EC military camouflage device that also has an energy storage function, making it an excellent choice for portable adaptive military camouflage.

Rapid developments in machine intelligence and human–machine interactions have opened widespread interest in artificial muscles owing to their huge application potential in soft robotics and biomedical fields. In this work, liquid crystal elastomer (LCE) and polyaniline (PANI)-doped LCE composite films were described, and their muscle-like actuation along with weight-lifting capabilities has been demonstrated. The composite films were prepared by doping 0.04, 0.08, 0.12, 0.16, and 0.24 wt % of PANI through a thiol-ene Michael addition reaction. Generally, LCEs show actuation in response to heat, at mesophase to isotropic transition, due to a change in the order of the system. PANI is employed to utilize light, infrared radiation (IR) in particular, to drive the actuation considering PANI’s excellent photothermal properties. All the films displayed liquid crystal properties, and the addition of PANI did not influence the transition temperatures much. The mechanical properties of the films were well above the standards (stress is >0.35 MPa and strain is >40%) required for artificial skeletal muscles. Among the composite films, LCE/PANI-2 showed good stiffness (stress: 1.63 MPa; Young’s modulus: 3.056 MPa) with high tensile strength. All the elastomer films exhibited remarkable thermal actuation, photoactuation, and incredible weight-lifting properties. Photoactuation was studied by using an IR diode laser source (808 nm, 2 W). The films showed response instantaneously, within 3–4 s of photoirradiation, in terms of longitudinal contraction, accompanied by lateral widening, and the response was reversible. During the contraction, the films were able to lift weight. A better performance was recorded for the LCE/PANI-2 film (0.08 wt % PANI) that lifted a weight of 120 g, which is 1538 times its own weight, when exposed to IR diode laser light. Our results strongly pointed the suitability and potential of the prepared films for application as artificial muscles.

Noncentrosymmetry (NCS) is essential for a second-harmonic nonlinear-optical (NLO) crystal; however, the tailored synthesis of NCS materials has historically posed significant challenges because the adjacent dipole moments of constituted NLO-active units in the structure tend to align in opposite directions, resulting in the NLO effect being canceled as in a centrosymmetric (CS) crystal. In this work, we propose a polar-layer-driven strategy, wherein a polarization-layered framework is constructed to constrain the dipole moment to align in the same direction, thereby facilitating the formation of the NCS structure. Taking the layered structure CS K₂ZnV₂O₇ as a prototype compound, a novel vandate K₄ZnV₅O₁₅Br (KZVB) was rationally synthesized via a multiple sites-oriented cosubstition method. KZVB containing two types of NLO-active units of V⁵⁺ d⁰ and Zn²⁺ d¹⁰ cations can be utilized as a mid-infrared NLO crystal with a remarkable NLO response comparable to that of nonoxide AgGaS₂. This work not only broadens the effective strategy for designing novel NCS compounds but also provides a progressive development of NLO materials.

Two-dimensional (2D) transition metal dichalcogenide (TMDC) semiconductors have been recognized as reliable candidates for future sub-10 nm physical gate length field-effect transistors (FETs). However, the device performance of 2D P-type devices is far inferior to that of N-type devices, which seriously hinders the development of complementary metal-oxide-semiconductor (CMOS) integrated circuits. Herein, we presented that two new 2D TMDC channel materials, ZrS₂ and HfS₂, can realize high-performance P-type MOSFETs through first-principles quantum transport simulations. Different from the 2D MoS₂ and WSe₂, the continuous in-plane p-orbitals at the valence band edge of 2D ZrS₂ and HfS₂ lead to a small hole effective mass of 0.24 m₀. As a result, 2D ZrS₂ and HfS₂ P-type MOSFETs with 10 nm gate length possess an on-state current (I_on) as high as 2000 μA/μm. Moreover, even when the gate length shrinks to 5 nm, the I_on can also reach ∼1500 μA/μm with the energy delay product ranging from 3 × 10^–30 to 1 × 10^–29 Js/μm, which are better than many other 2D P-type MOSFETs like MoS₂ and WSe₂. Our work demonstrates that 2D ZrS₂ and HfS₂ are competitive channel materials for constructing future sub-10 nm P-type high-performance FETs.

Herein, we describe a dual catalytic strategy that employs dihydroquinazolinones, derived from ketone analogs, as versatile intermediates for acylation via α C–C cleavage with 2-pyridyl esters, facilitating the efficient synthesis of a variety of ketones. The reaction accommodates a wide range of ketones and carboxylic acids, showing tolerance to various functional groups. The versatility of this synthetic technique is further highlighted through its application in the late-stage modification of pharmaceuticals and biologically active natural products.

The focus is on developing alternative molecular catalysts using main-group elements and implementing strategic improvements for sustainable hydrogen production. For this purpose, a FB corrole with a (2-(2-((4-methylphenyl)sulfonamido)ethoxy)phenyl) group inserted into the meso position (C-10) of the corrole, along with its high-valent (corrolato)(oxo)antimony(V) dimer, was synthesized. In the crystal structure analysis of the FB corrole and the (corrolato)(oxo)antimony(V) dimer complex, it was noted that the sulfonamido group in the ligand periphery sits atop the corrole ring. The electrochemical hydrogen evolution reaction (HER) of the (corrolato)(oxo)antimony(V) dimer was studied and compared with a previously reported (corrolato)(oxo)antimony(V) complex, which lacks hydrogen-bond donor groups in the secondary coordination sphere. The newly designed molecules, featuring hydrogen-bond donor groups in the secondary coordination sphere, demonstrated clear superiority in the electrochemical HER. Controlled potential electrolysis was employed to evaluate the charge accumulation associated with hydrogen generation in a homogeneous three-electrode system in the presence of 50 mM TFA. The produced hydrogen exhibits a Faradaic efficiency of approximately 80.96%, a turnover frequency (TOF) of 0.44 h^–1, and a production rate of 52.83 μL h^–1, highlighting the effective catalytic activity of the (corrolato)(oxo)antimony(V) dimer in hydrogen evolution.

Closed-form expressions for the analysis of Dark state Exchange Saturation Transfer (DEST) NMR experiments, a powerful experimental tool for characterizing exchange processes involving the interaction of NMR visible species with very high molecular weight partners, is presented. Essentially identical exchange and relaxation parameters are derived from the analytical and numerical best fits of the DEST profiles obtained for a protein construct derived from huntingtin exon-1, comprising the N-terminal amphiphilic sequence followed by a seven-residue glutamine repeat, htt^NTQ₇, in the presence of small (SUV) and large (LUV) unilamellar lipid vesicles. The use of analytical expressions significantly speeds up the fitting of experimental DEST profiles to a two-state exchange model and simplifies the analysis of the DEST effects.

In modern society, there is widespread interest in the development of sustainable and functional polymer materials. Herein, three imine-containing diphenol hardeners with different numbers of conjugated benzene rings and one trifunctional phenol-amine hardener were successfully synthesized using vanillin, a biobased feedstock derived from lignin. The curing kinetics of epoxy systems based on these hardeners was studied using Kissinger and Ozawa methods. The obtained liquid crystalline epoxy resins cured by these hardeners show high glass transition temperatures (136–144 °C), mechanical strengths (76.2–119.3 MPa), and intrinsic thermal conductivities (0.26–0.32 W m^–1 K^–1). The X-ray diffraction results indicate that the structural order of the cured epoxy resins increases with the number of benzene rings in the hardeners. In addition, the incorporation of aromatic imine bonds endows the cured epoxy resins with dynamic structures and recyclability. These epoxy resins can be reprocessed through hot pressing and are degradable in acid or amine solutions. Notably, the degradation products in the acid solution can be used to prepare the epoxy resins. Compared with their pristine counterparts, the reprocessed and chemically recycled epoxy resins demonstrate high retention of glass transition temperature, tensile strength, and thermal conductivity. Overall, the findings in this work offer a simple and effective approach to develop recyclable liquid crystalline epoxy resins with high thermal conductivity from biobased hydroxybenzaldehydes.