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Atomically dispersed metal catalysts maximize atom efficiency and display unique catalytic properties compared with regular metal nanoparticles. However, achieving high reactivity while preserving high stability at appreciable loadings remains challenging. Here we solve the challenge by synergizing metal–support interactions and spatial confinement, which enables the fabrication of highly loaded atomic nickel (3.1 wt%) along with dense atomic copper grippers (8.1 wt%) on a graphitic carbon nitride support. For the semi-hydrogenation of acetylene in excess ethylene, the fabricated catalyst shows extraordinary catalytic performance in terms of activity, selectivity and stability—far superior to supported atomic nickel alone in the absence of a synergizing effect. Comprehensive characterization and theoretical calculations reveal that the active nickel site confined in two stable hydroxylated copper grippers dynamically changes by breaking the interfacial nickel–support bonds on reactant adsorption and making these bonds on product desorption. Such a dynamic effect confers high catalytic performance, providing an avenue to rationally design efficient, stable and highly loaded, yet atomically dispersed, catalysts. Synergizing metal–support interactions and spatial confinement through atomic copper grippers boost the dynamics of highly loaded atomic nickel for high activity, high thermal/chemical stability and unprecedented coke inhibition in hydrogenation reactions.

Selective hydrogenation is an important industrial catalytic process in chemical upgrading, where Pd-based catalysts are widely used because of their high hydrogenation activities. However, poor selectivity and short catalyst lifetime because of heavy coke formation have been major concerns. In this work, atomically dispersed Pd atoms were successfully synthesized on graphitic carbon nitride （g-C3N4） using atomic layer deposition. Aberration-corrected high-angle annular dark-field scanning transmission electron microscopy （HAADF-STEM） confirmed the dominant presence of isolated Pd atoms without Pd nanoparticle （NP） formation. During selective hydrogenation of acetylene in excess ethylene, the g-C3N4-supported Pd NP catalysts had strikingly higher ethylene selectivities than the conventional Pd/Al2O3 and Pd/SiO2 catalysts. In-situ X-ray photoemission spectroscopy revealed that the considerable charge transfer from the Pd NPs to g-C3N4 likely plays an important role in the catalytic performance enhancement. More impressively, the single-atom Pd1/C3N4 catalyst exhibited both higher ethylene selectivity and higher coking resistance. Our work demonstrates that the single-atom Pd catalyst is a promising candidate for improving both selectivity and coking-resistance in hydrogenation reactions.

Hydrogenation of nitriles represents as an atom-economic route to synthesize amines, crucial building blocks in fine chemicals. However, high redox potentials of nitriles render this approach to produce a mixture of amines, imines and low-value hydrogenolysis byproducts in general. Here we show that quasi atomic-dispersion of Pd within the outermost layer of Ni nanoparticles to form a Pd 1 Ni single-atom surface alloy structure maximizes the Pd utilization and breaks the strong metal-selectivity relations in benzonitrile hydrogenation, by prompting the yield of dibenzylamine drastically from ∼5 to 97% under mild conditions (80 °C; 0.6 MPa), and boosting an activity to about eight and four times higher than Pd and Pt standard catalysts, respectively. More importantly, the undesired carcinogenic toluene by-product is completely prohibited, rendering its practical applications, especially in pharmaceutical industry. Such strategy can be extended to a broad scope of nitriles with high yields of secondary amines under mild conditions. While nitrile hydrogenation may provide an appealing means to obtain secondary amines, poor selectivity plagues heterogeneous catalysts. Here, authors report single-atom palladium on nickel catalysts to afford high yields of secondary amines from a broad range of parent nitriles.

Natural cracks are prone to form in toppling deformed rock masses during the toppling process, and these cracks are likely to undergo hydraulic fracturing failure under the action of high water head. This paper leverages the advantage of the extended finite element method (XFEM) in simulating crack propagation, considers the effect of water pressure on the crack surface, conducts numerical simulation and analysis on the hydraulic fracturing of cracks in toppling deformed rock masses, and studies the influences of different crack lengths, rock formation dip angles and crack surface water pressures on crack propagation. The main conclusions are as follows: (1) After hydraulic fracturing occurs in the rock mass, with the continuous rise in the water level, the crack propagation rate is slow first and then fast. When the water pressure is low, microcracks extend slowly; when the water pressure reaches a certain level, the rock formation cracks expand rapidly and eventually fracture. (2) Under the same water pressure, rock formations with longer initial crack lengths are more prone to hydraulic fracturing, and their cracks expand faster; rock formations with a dip angle of 45° are more likely to undergo hydraulic fracturing than those with other dip angles, while rock formations with a dip angle close to 90° are hardly susceptible to hydraulic fracturing. (3) The instability failure mechanism of hydraulic fracturing in toppling deformed rock masses is tension shear action. As the fissure water pressure rises, the tensile stress at the crack tip will increase sharply. Once new microcracks appear in the initial crack, it will be in an unstable expansion state.

The interfacial contact between NiO x and self-assembled monolayers (SAMs) in wide-bandgap (WBG) subcells limits the efficiency and stability of all-perovskite tandem solar cells (TSCs). The strongly acidic phosphoric acid (PA) anchors in common PA-SAMs corrode reactive NiO x , undermining device stability. Moreover, SAM aggregation leads to interfacial losses and significant open-circuit voltage (V OC ) deficits. Here, we introduce boric acid (BA) as a milder anchoring group that chemisorbs onto NiO x via strong – BO 2 - –Ni coordination. A benzothiophene-fused head group enhances interfacial bonding through S–Ni orbital interactions, yielding higher binding energy than PA-SAMs. This design also promotes homogeneous SAM formation without aggregation. Resultantly, the WBG cell exhibits an improved PCE to 20.1%. When integrated with narrow bandgap (NBG) subcell, the two-terminal (2T) TSCs achieve an ameliorative PCE of 28.5% and maintain 90% of the initial PCE after maximum power point tracking (MPP) under 1 sun illumination for 500 h. The suboptimal interfacial contacts between nickel oxide and self-assembled monolayers in wide bandgap subcells limit the photovoltaic efficiency and stability. Here, authors employ boric acid as an anchoring group for chemisorption, achieving efficiency of 28.5% for two-terminal tandem solar cells.

Ammonia borane (AB) is regarded as a promising chemical hydrogen-storage material due to its high hydrogen content, non-toxicity, and long-term stability under ambient temperature. However, constructing advanced catalysts to further promote the hydrogen production still remains a challenge for the hydrolysis of AB. Herein, we report a novel oxygen modified CoP 2 (O-CoP 2 ) material with dispersed palladium nanoparticles (Pd NPs) as a highly efficient and sustainable catalyst for AB hydrolysis. The modification of oxygen could optimize the catalytic synergy effect between CoP 2 and Pd NPs, achieving enhanced catalytic activity with a turnover frequency (TOF) number of 532 min −1 and an activation energy ( E a ) value of 16.79 kJ·mol −1 . Meanwhile, reaction kinetic experiments prove that the activation of water is the rate-determining step (RDS). The water activation mechanism is revealed by quasi in-situ X-ray photoelectron spectroscopy (XPS) and in-situ X-ray absorption fine structure (XAFS) measurements. The activation of water leads to the production of -H and -OH groups, which are further adsorbed on the oxygen atoms in P-O bond and Pd atoms, respectively. In addition, density functional theory (DFT) calculations indicate that the introduced oxygen facilitates the adsorption and activation of water molecules. This novel modulation strategy successfully sheds new light on the development of advanced catalysts for hydrolysis of AB and beyond.

All-perovskite tandem solar cells (PTSCs) demonstrate exceptional potential to surpass the Shockley-Queisser (SQ) theoretical limit. However, practical implementation faces critical challenges due to a self-reinforcing photothermal-mechanical degradation mechanism originating from multiscale physical couplings. In this study, a multifunctional polyamine ligand triphenyltriamine thiophosphate (TPTA) was introduced into the tin-lead (Sn-Pb) perovskite solution system to establish an I-Sn-N coordination-mediated lattice stabilization framework, and the photothermal-mechanical coupling path was cut off from multiple aspects such as suppressing periodic oscillations and regulating stress. Consequently, single-junction Sn-Pb perovskite solar cells (PSCs) achieve a power conversion efficiency (PCE) of 23.4% and retaining 94.9% of initial performance after 950 hours of maximum power point (MPP) tracking. When the device is integrated into the 2-terminal (2 T) tandem architecture, its PCE reaches a significant level of 29.6 % (certified PCE of 28.9%), and 93.4% of the initial efficiency can be maintained after 900 hours continuous operation. Practical implementation of all-perovskite tandem solar cells faces challenges due to the self-reinforcing photothermal-mechanical degradation mechanism. Here, authors employ a polyamine ligand to establish I-Sn-N coordination for stabilizing lattice framework, achieving device efficiency of 29.6%.

All-perovskite tandem solar cells (PTSCs) offer a promising approach to surpass the Shockley-Queisser (SQ) limit, driven by efficiently reducing thermalization and transmission losses. However, the efficiency and stability of the narrow-bandgap (NBG) subcells, which are essential for PTSC performance, remain severely constrained by challenges such as lattice instability, strain accumulation and halide migration under illumination. This study introduces a rigid sulfonate-based molecule, sodium naphthalene-1,3,6-trisulfonate (NTS), into tin-lead (Sn-Pb) perovskites, where it strengthens the Sn-I bond through Sn-trisulfonate coordination and reduces light-induced dynamic lattice distortions via the rigid NTS backbone. These molecular interactions alleviate strain heterogeneity within the lattice and homogenize the Sn-Pb compositional gradient, thereby enhancing the structural integrity and long-term stability of Sn-Pb perovskites under operational conditions. As a result, Sn-Pb single-junction perovskite solar cells (PSCs) achieve a power conversion efficiency (PCE) of 23.2%. When integrated into a tandem configuration, the device attains an impressive PCE of 29.6% (certified PCE of 29.2%, one of the highest certified efficiencies to date), with 93.1% of the initial efficiency retained after 700 h of continuous operation. By stabilizing the lattice structure, this work lays a solid foundation for achieving both high efficiency and long-term durability in next-generation perovskite photovoltaics. The efficiency of narrow bandgap subcells is hindered by structural instability and strain accumulation. The authors introduce a rigid sulfonate molecule that suppresses light-induced lattice distortions, enabling certified 29.2% efficiency in all-perovskite tandem solar cells.

Constructing nitrogen (N2) adsorption and activation sites on semiconductors is the key to achieving efficient N2 photofixation. Herein, Mn–W dual‐metal sites on WO3 are designed toward efficient N2 photoreduction via controlled Mn doping. Impressively, the optimal 2.3% Mn‐doped WO3 (Mn‐WO3) exhibits a remarkable ammonia (NH3) production rate of 425 µmol gcat.−1 h−1, representing the best catalytic performance among the ever‐reported tungsten oxide‐based photocatalysts for N2 fixation. Quasi in situ synchrotron radiation X‐ray spectroscopy directly identifies that the Mn–W dual‐metal sites can enhance the polarization of the adsorbed N2, which is beneficial to the N2 activation. Further theoretical calculations reveal that the increased polarization is originated from the electron back‐donation into the antibonding orbitals of the adsorbed N2, hence lowering the reaction energy barrier toward the N2 photofixation. The concept of dual sites construction for inert molecule activation offers a powerful platform toward rational design of highly efficient catalysts for nitrogen fixation and beyond. The optimal 2.3% Mn‐doped WO3 exhibits an impressive NH3 production rate of 425 µmol gcat.−1 h−1. Further quasi in situ synchrotron radiation X‐ray spectroscopy and theoretical calculations reveal that the Mn–W dual‐metal sites can enhance the polarization of the adsorbed N2, hence lowering the reaction energy barrier toward the N2 photofixation.

The key to designing photocatalysts is to orient the migration of photogenerated electrons to the target active sites rather than dissipate at inert sites. Herein, we demonstrate that the doping of phosphorus (P) significantly enriches photogenerated electrons at Ni active sites and enhances the performance for CO2 reduction into syngas. During photocatalytic CO2 reduction, Ni single‐atom‐anchored P‐modulated carbon nitride showed an impressive syngas yield rate of 85 μmol gcat−1 h−1 and continuously adjustable CO/H2 ratios ranging from 5:1 to 1:2, which exceeded those of most of the reported carbon nitride‐based single‐atom catalysts. Mechanistic studies reveal that P doping improves the conductivity of catalysts, which promotes photogenerated electron transfer to the Ni active sites rather than dissipate randomly at low‐activity nonmetallic sites, facilitating the CO2‐to‐syngas photoreduction process. For a Ni single‐atom‐decorated carbon nitride catalyst (Ni1/P‐CN), orienting the migration of photogenerated electrons to the carbon sites and Ni sites promotes the production of H2 and CO during photocatalytic CO2 reduction reactions, respectively. As such, syngas with adjustable CO/H2 ratios could be obtained for Ni1/P‐CN by manipulating photogenerated electron flow to the target active sites.