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[Display omitted] • Electrons are redistributed as Mg&MoP/CN loaded at a reverse interfacial position. • Interfacial MoP behaves as the electron collecting sites to improve the activity. • Exterior Mg functions as the catalyzing sites to tackle the selectivity challenge. • Selective and efficient CH 4 evolution are achieved by a Z-scheme reaction pathway. Constructing photocatalysts with dual-function active sites can coordinate the photogenerated electrons transfer and the adsorption energy of key intermediates, thereby converting CO 2 into valuable methane with high efficiency. However, the role that the interfacial position of functional catalysts played in determining the activity and selectivity of CO 2 photoreduction remains unclear. Herein, we regulated the action interface and synergistic effect of magnesium nitrate hydroxide and molybdenum phosphide (Mg & MoP) to modify polymeric carbon nitride (PCN), and found the function-oriented Mg-MoP/PCN exhibits superior performance for catalyzing CO 2 -to-CH 4 in pure water, with a rate of 24.45 μmol h−1 g−1 and 95.3 % selectivity. Theoretical and experimental studies reveal that interfacial layer of MoP promotes the evolutionary activity by facilitating the electron transfer while exterior layer of Mg functions as the catalyzing sites to tackle the selectivity challenge by promoting CO 2 adsorption and CO* stabilization. The synergistic interaction of function-oriented Mg&MoP realizes selective CH 4 evolution with high efficiency via a Z-scheme pathway. The interfacial position of bifunctional catalysts is vital for regulating CO 2 photoreduction activity and product selectivity. [ABSTRACT FROM AUTHOR]

[Display omitted] • Solvent-redox hydrothermal process was employed to constructure MnO x –D oxides. • MnO x –D catalyst exhibites superior catalytic activity for aerobic oxidation of biomass–derived R–CH 2 –OH. • Adsorbed H 2 O on MnO x –D catalyst was found to enhance its superior catalytic activity. Manganese oxides (MnO x) have been emerged as highly active catalysts for the aerobic oxidation of biomass-derived compounds. Herein, a facile urea–redox hydrothermal method was employed to scalable synthesis of MnO x oxides with surface abundant unsaturated Mn and O species. The defective MnO x (MnO x –D) catalyst exhibits remarkable catalytic performance, enabling the room-temperature aerobic oxidation of biomass–derived alcohols with yields exceeding 99%. This represents a substantial 90.8-fold increase in activity compared to commercial MnO 2. Moreover, MnO x –D catalyst demonstrates broad substrate scopes for various biomass–derived alcohols and displays recyclability for the aerobic oxidative conversion of 5-hydroxymethylfurfural (HMF) over five cycles. Through a comprehensive analysis involving X–ray photoelectron spectroscopy (XPS), in–situ infrared (IR) spectroscopy, and controlled experiments, it is established that the presence of surface–adsorbed H 2 O species on MnO x –D catalyst significantly influences its catalytic performance. Mechanism studies reveal that the aerobic oxidation of biomass–derived R–CH 2 –OH compounds into the corresponding aldehydes can proceed via radical and non–radical pathways. Notably, the catalytic activity of MnO x –D catalyst in both pathways is mediated by the surface adsorbed H 2 O species. In the radical route, surface adsorbed H 2 O and O 2 species are converted into active •OH radical species, while in the non–radical route, surface adsorbed H 2 O can form a complex of HMF––H 2 O species. Both processes enhance the abstraction of H from the O–H and C–H bonds in the R–CH 2 –OH compounds on MnO x –D catalyst. This discovery could potentially guide the development of efficient metal oxidic catalysts for the oxidation of biomass–derived R–CH 2 –OH compounds. [ABSTRACT FROM AUTHOR]

• Electrostatic spinning construction of 3D PVDF/PAN @Zn powder frameworks. • Mechanical stresses on fibre filaments and uniform stripping of zinc powder inhibit dendrite growth. • Larger surface area, suitable pore size and tunable N/P ratio are key merits. Zinc foil metal anodes in aqueous zinc ion batteries (AZIBs) are impaired by uncontrollable dendrite growth, resulting in low Coulombic efficiency (CE) and limited lifetime. The tunability of zinc powder provides a perfect alternative for anodes. But their rough spherical surfaces possibly make them more susceptible to corrosion and dendrite growth. We hereby utilise electrostatic spinning to weave zinc powder into polyacrylonitrile/ Polyvinylidene fluoride (PVDF/PAN) fiber filament to produce a new three-dimensional porous zinc anode (PF@Zn). Stable and flexible structure of the constructed fiber filament framework avoids direct contact of the aqueous electrolyte with the collector while relieving the stresses generated by dendrite growth. Moreover, when galvanizing or stripping, the zinc powder woven into the fiber network efficiently homogenizes the Zn2+ ion flux for a stable zinc cycle. Accordingly, the PF@Zn anode battery has a superior cycle life (240 h) and an increased Coulombic efficiency (99.1 %). An assembled C//PF@Zn capacitor has an impressive 96.6 % capacity retention after 3000 cycles. The study offers a scalable approach to modifying metal powder electrodes and transforming them into high-performance batteries. [ABSTRACT FROM AUTHOR]

The chitosan-induced self-assembly strategy is developed to construct MXene into a flexible 3D Ti 3 C 2 T x @Chitosan film. The film with 3D ordered and porous structure shows excellent rate capability and low mass-loading dependence. The hydrophilic crosslinked chitosan, which are interconnected and interwoven with MXene nanosheets, also endows the film with enhanced mechanical strength and flexibility. [Display omitted] • 3D Ti 3 C 2 T x @Chitosan film was prepared via a chitosan-induced self-assembly strategy. • The 3D ordered and porous electrode exhibited enhanced electrochemical performance. • The mechanical properties for the MXene-based composite film are significantly enhanced. • The assembled symmetric supercapacitor delivers ultra-high power density and flexibility. MXenes with outstanding electric conductivity and surface chemistry are promising materials for future energy storage. However, processing MXenes into free-standing films can lead to restacking and aggregation of the 2D nanosheets, which limits the ionic kinetics within materials. Current solutions are difficult for films to satisfy both rate performance and flexibility. Herein, we propose a novel chitosan-induced self-assembly strategy to construct MXene into flexible Ti 3 C 2 T x @Chitosan films with 3D ordered and porous structure. The interconnected 3D network provides fast transport channels for electrons and electrolyte ions. Therefore, the film exhibits excellent rate capability and low mass-loading dependence. The Ti 3 C 2 T x @Chitosan film with a high mass loading of 4 mg−2 delivers a capacitance of 245.2F g−1 at 2 V s−1, which demonstrates 57.1% capacitance retention with 400-fold scan rate increase. The crosslinked chitosan is interconnected and interwoven with MXene nanosheets, resulting in enhanced mechanical strength and flexibility for Ti 3 C 2 T x @Chitosan. Furthermore, by applying Ti 3 C 2 T x @Chitosan film to assemble flexible symmetrical supercapacitors, an ultra-high power density of 143.2 μWh cm−2 can be attained. This work develops a simple route for assembling 2D MXene into 3D high-flexible porous films as state-of-the-art electrodes for high-rate pseudocapacitive energy storage. [ABSTRACT FROM AUTHOR]

Rare earth oxalates as ion exchange materials achieve the rapid and highly selective removal of strontium(II) from complex aqueous solutions for radionuclide remediation. [Display omitted] • A pioneering work on rare earth oxalates (Ln-ox) for the efficient Sr2+ removal. • Ln-ox compounds have high water stability and irradiation resistance. • Eu-ox exhibits fast kinetics (3 min) and high selectivity in Sr2+ ions adsorption. • The Sr2+ removal mechanism of Ln-ox is illuminated to be ion exchange. • Channel size, [Me 2 NH 2 ]+, affinity of C 2 O 4 2− for Sr2+ are crucial for adsorption. Radiostrontium remediation is of vital significance due to the hazard of radiostrontium to ecological environments and human health. However, it remains a challenge to effectively remove Sr2+ ion from complex water environments due to its solubility, mobility and influence of interfering ions. Herein, we report a series of rare earth oxalates with three-dimensional (3D) anionic microporous frameworks, namely [Me 2 NH 2 ][Ln(C 2 O 4) 2 (H 2 O)]·3H 2 O (Ln-ox ; Ln = Y, Nd, Sm, Eu, Gd, Er, Tm, Yb). Ln-ox can be easily synthesized in large scale and possess high water stability and radiation resistance. The rapid and highly selective uptake of Sr2+ ion is achieved by Eu-ox with fast kinetics (3 min) and K d Sr value up to 2.61 × 105 mL/g. Under high concentrations of interfering metal ions (M = Na+, Cs+, Mg2+ and Ca2+), Eu-ox exhibits high selectivity for Sr2+ with high separation coefficient SF Sr/M. The Sr2+ removal mechanism has been revealed and attributed to the ion exchange between Sr2+ and [Me 2 NH 2 ]+ cations. Further, by comparing a series of rare earth oxalate frameworks, it is found that the occurrence of ion exchange in 3D microporous rare earth oxalate materials is related to the channel size and the interaction of exchangeable cations with anionic framework. The strong complexation ability of oxalate groups to Sr2+, the large channel size of Eu-ox and the exchangeable [Me 2 NH 2 ]+ cations are crucial factors for Sr2+ ion exchange. Rare earth oxalate frameworks as ion exchange materials are firstly used for the Sr2+ removal, confirming the potential of rare earth oxalates in radionuclide remediation. [ABSTRACT FROM AUTHOR]

Interface engineering has been employed on commercial Bi 0.5 Sb 1.5 Te 3 (BST) to obtain synergistically enhanced thermoelectric performance via incorporating amorphous Sb 2 S 3 nano spheres. [Display omitted] • Conducting interface engineering via incorporating Sb 2 S 3 in Bi 0.5 Sb 1.5 Te 3. • Decoupling thermal and electrical properties via introducing Sb/BST interfaces. • Obtaining a high zT of ∼ 1.31 at 330 K in Bi 0.5 Sb 1.5 Te 3 -0.4%Sb 2 S 3. Tremendous efforts have been focusing on the improvement of p-type (Bi, Sb) 2 Te 3 -based thermoelectric materials for commercial applications. In this study, we achieve versatile interface engineering through a surface decoration of Bi 0.5 Sb 1.5 Te 3 by amorphous Sb 2 S 3 combining with spark plasma sintering, which introduces semi-coherent Sb/Bi 0.5 Sb 1.5 Te 3 interfaces and dopes S into Bi 0.5 Sb 1.5 Te 3. Semi-coherent Sb/Bi 0.5 Sb 1.5 Te 3 interfaces strongly scatter phonons and lower energy carriers, leading to decreased thermal conductivity and increased Seebeck coefficient, while the electrical conductivity is not sacrificed due to the compromise of the slightly reduced carrier mobility by interfacial scattering and the increased carrier concentration by S doping. Benefited from the decoupled thermoelectric properties, a significantly enhanced power factor of 3345.40 μW m−1 K−2 and a low thermal conductivity of 0.78 W m−1 K−1 is obtained in Bi 0.5 Sb 1.5 Te 3 -0.4%Sb 2 S 3 , leading to a high peak zT of ∼ 1.31 at 330 K, which shows a 54% enhancement compared with pristine Bi 0.5 Sb 1.5 Te 3. Moreover, a conversion efficiency of ∼ 7.6% can be predicted in a single leg Bi 0.5 Sb 1.5 Te 3 -0.4%Sb 2 S 3 -based module under a cold side temperature of 300 K and hot side temperature of 480 K. This study paves a facile amorphous Sb 2 S 3 induced interface engineering strategy for the development of high performance (Bi,Sb) 2 Te 3 -based thermoelectric materials. [ABSTRACT FROM AUTHOR]