Advanced Energy Materials (United States)

The self-assembly of small molecules with a suitable metal ion is a critical bottom-up approach for preparing solution-processable metallo-supramolecular polymers and to realize their potential as a photocatalyst. Herein, we report the design, synthesis, self-assembly, and gelation behavior of a low-molecular-weight gelator (LMWG) based on a pyrene core connected to four terpyridine units (TPY-PY) through amide linkages. TPY-PY forms an organogel (OG) in the DMSO/H2O mixed solvent with a nanofibrillar morphology. In contrast, the introduction of RuII with the LMWG resulted in a Ru-TPY-PY coordination polymer gel (CPG) with a cross-linked fibrillar nanostructure with a length of several micrometers. The Ru-TPY-PY CPG exhibited highly efficient photoreduction of CO2 to CO (yield: 10.79 mmol g–1, rate: 899.17 μmol g–1 h–1) with 90% selectivity, under visible light irradiation, and in the presence of triethylamine (TEA) as a sacrificial electron donor. Moreover, metallo-supramolecular polymers with diverse nanomorphologies, formed at different RuII to TPY-PY ratios, showed different efficiencies in the photo reduction of CO2 to CO. Among these nanostructures, 1D nanofibers exhibited enhanced photocatalytic activity compared to the nanospheres for CO2 reduction, attributed to the abundance of catalytically active sites on their surface with facile CO2 diffusion capabilities. Furthermore, femtosecond transient absorption spectroscopy, in situ DRIFTS analysis, and DFT calculation help to understand the feasibility of the electron transfer pathway, and reaction mechanism in the overall process. The “soft” processable hybrid metal–organic supramolecular polymers that integrate both the catalytic site and the light-absorbing units are a class of catalysts showing efficient CO2 photoreduction to CO.

The semihydrogenation of phenylacetylene to styrene is a critical process for styrene purification, and the rational design of catalysts with high activity and selectivity remains a key challenge. Transition metal containing zeolite catalysts offer unique advantages in semihydrogenation, while the reaction mechanism remains unclear, thereby hindering the performance optimization of catalysts. Using density functional theory calculations, a representative Ni@FAU catalyst, with Lewis pairs comprising a FAU six-membered ring-confined Ni(II) ions and adjacent framework oxygen atoms as the active sites, are investigated for phenylacetylene semihydrogenation. At 0 K, H2 fails to dissociate directly at clean Lewis pairs, but phenylacetylene preadsorption (PhC≡CH_Ni*) at Ni sites promotes H2 dissociation at the classical Lewis pairs, forming [H_Oz+H_Ni]* intermediates. These intermediates can convert to [H_Oz+H_Oz]* via hydride/proton transfer, with PhC≡CH_Ni* stabilizing both [H_Oz+H_Ni]* and [H_Oz+H_Oz]* intermediates and facilitating hydrogen transfer. Analysis of four phenylacetylene hydrogenation pathways shows that ethylbenzene formation is suppressed by a high barrier (2.46–2.71 eV) for the second H2 dissociation (rate-determining step) due to steric hindrance. In contrast, styrene formation is kinetically favorable, with Pathway 3 (α-carbon first, then β-carbon) being optimal, featuring a low rate-determining step barrier (0.67 eV) for proton transfer. This work clarifies how the Ni@FAU catalyst achieves high styrene selectivity by inhibiting overhydrogenation to ethylbenzene, aligning well with experimental observations, and further deepens mechanistic understandings of phenylacetylene semihydrogenation over the Ni@FAU catalyst for the rational design of selective hydrogenation catalysts.

The self-assembly of nucleotides into sophisticated biomolecular architectures offers a powerful platform for developing advanced functional materials. Herein, we exploit the innate chirality and metal-coordination capability of nucleotides to fabricate biomolecular coordination polymers with circularly polarized luminescence (CPL). By integrating nucleotides (AMP, GMP, UMP, CMP) with lanthanide-based deep eutectic solvents (DESs) that serve as both a reactive medium and a source of red and green emission, we successfully constructed nucleotide-lanthanide coordination polymers. These biomolecular complexes not only exhibited characteristic lanthanide emissions but also demonstrated significant CPL activity. Remarkably, a white-light-emitting coordination polymer with white circularly polarized luminescence (W-CPL) was achieved by incorporating blue-emitting carbon dots into the AMP-coordinated system, forming a solvent-free supramolecular assembly. Furthermore, a prototype light-emitting diode (LED) device was fabricated by coating these nucleotide-based complexes onto a UV chip, successfully generating electrically driven polarized visible light. This work underscores the immense potential of nucleotide biomolecules as versatile scaffolds for crafting next-generation polarized optical materials and devices.

We investigate the coupled evolution of heterogeneous strain, crystallinity, and stress fields in natural rubber (NR) sheets containing a circular hole during uniaxial stretching, with a focus on how strain-induced crystallization (SIC) influences local stress concentration at structural discontinuities. By high-resolution digital image correlation, an empirical strain-crystallinity relationship and a hyperelasticity analysis firmly grounded in stress–strain data obtained under diverse deformation modes, we quantitatvely map the spatial distributions of strain, SIC, and stress in the extreme vicinity (≈0.2 mm) of the defect. Local strain concentration at the lateral hole edges triggers pronounced SIC, resulting in strong stiffening and a stress concentration factor (Kt*) as high as 4.5─significantly exceeding classical elastic predictions. Upon further stretching, Kt* plateaus, eventually as SIC develops in the far-field region, promoting a more homogeneous stress distribution. The SIC-induced stiffening also generates a highly anisotropic stress field near the hole edges due to preferential reinforcement along the crystalline orientation. The localized SIC causes characteristic hole-shape evolution, where the hole becomes increasingly elongated along the stretching axis compared with the fully amorphous state. These findings elucidate the fundamental interplay between SIC and local stress concentration in elastomers with structural discontinuities and provide mechanistic insights for designing defect-tolerant, high-toughness rubber materials.

Although hexacoordinated aluminum species exhibit moderate acidity, which is advantageous for many catalytic reactions relative to the stronger acidity of tetracoordinated aluminum, their structural instability in porous frameworks significantly limits the specific surface area and pore stability of materials. To address these challenges, we report an innovative stepwise deposition strategy for constructing Al2O3/MCM-41-x materials with γ-Al2O3 decorated in the inner wall of MCM-41. The inner aluminum deposition originated from the preferential hydrolysis of AlO2– remains hexacoordinated state as γ-Al2O3 generating moderately Lewis acid sites. The outer silica deposition layer forms an MCM-41 framework, resulting in long-range ordered mesoporous material Al2O3/MCM-41 with hexagonal channels. This structure delivers a high specific surface area while simultaneously enhancing the stability of Al2O3. With Al2O3/MCM-41 as support, the optimal catalyst Ru/Al2O3/MCM-41 achieved 97.1% aniline conversion (160 °C, 3.0 MPa H2), a value three times higher than that of conventional Ru/Al2O3 (32.3%). This significant enhancement can be attributed to the synergistic effects of a high surface area, ordered mesoporous structure, and dominant Lewis acidity. This work establishes a pioneering structure featuring Al2O3 decoration in the mesopores of MCM-41 via stepwise deposition self-assembly strategy, providing a promising mesoporous support for hydrogenation catalysis and industrial applications.

Correction for ‘High-entropy engineering tuning electrochemical activity and stability of a layered double perovskite oxygen electrode for high-performance protonic ceramic cellsʼ by Zhipeng Sun et al. , J. Mater. Chem. A , 2026, 14 , 4124–4135, https://doi.org/10.1039/D5TA06570D.