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Employing a facile one-pot hydrothermal synthesis approach, in this work, we achieved the successful synthesis of a CuCoO2/CuO heterostructure, which was characterized by an atomic-scale intimately bonded interface. This can be utilized as a reference for the synthesis of heterostructures involving multiple compounds and their secondary phases. Notably, the CuCoO2/CuO heterostructure stands out for its superior performance in photocatalytic overall water splitting without relying on additional co-catalysts or sacrificial agents. In addition, this heterostructure displayed excellent electrocatalytic activity, photocatalytic activity for the degradation of trichloromethane, and promising PEC performance when utilized as a photocathode. A pivotal feature of the CuCoO2/CuO heterostructure is its capacity to efficiently inhibit the migration of photogenerated holes from CuCoO2 to CuO. This was attributed to the synergistic effects between the intrinsic interface electric field and pronounced valence band offset. Interestingly, this mechanism overcomes the traditional limitations associated with type-I heterostructures. Consequently, the two half-reactions of the overall water splitting process are selectively localized on opposite facets of the CuCoO2/CuO heterostructure. Overall, our findings elucidate the profound implications of band alignment in these heterostructures, offering pivotal insights for the innovation and optimization of advanced heterostructure photo(electro)catalytic materials. [ABSTRACT FROM AUTHOR]

Herein, we report a poly(N-isopropylacrylamide) sulfide (PNIPAM-S-) brush-tethered and Pd nanoparticle (NP) loaded UiO-66 type NMOF, namely Pd@UiO-66-S-PNIPAM, based on a NMOF–polymer covalent composite approach. The obtained multifunctional composite material can be a highly efficient Pickering emulsifier to stabilize the toluene-in-water emulsion; furthermore, it promotes the biphasic chlorobenzene (CB) dechlorination at the toluene–water interface in excellent yields at room temperature. More importantly, the Pd@UiO-66-S-PNIPAM emulsifier is thermo-responsive and can trigger emulsification at room temperature (25 °C) and demulsification at an elevated temperature (45 °C) of the toluene droplets, which makes product–catalyst in situ separation and recycling feasible. This temperature switchable Pickering emulsion catalytic system can be reused at least five times without any loss of its catalytic activity. [ABSTRACT FROM AUTHOR]

Designing an all pH value hydrogen evolution reaction (HER) electrocatalyst with low cost and high activity is urgently needed for future energy storage and conversion systems. Metal–organic frameworks (MOFs) with well-defined pore structures and various metal sources provide feasible platforms for the design of efficient electrocatalysts. However, MOFs as crystalline materials are mostly in crystal or powder form, which would hinder their practical application. Herein, polyoxometalate-based MOFs (POMOFs) were synthesized on carbon cloth (CC) through a facile and general solid-phase hot-pressing method for the first time. The thus-obtained POMOFs/CC can be converted into three phase bimetallic phosphides coated with porous carbon on CC through a phosphidation process, show high electrocatalytic stability over a wide pH range (pH, 0–14) and possess excellent HER performance with low overpotential (e.g., 90.5 mV at 10 mA cm−2 in 1 M KOH). Moreover, the POMOFs/CC derived phosphides present high selectivity for H2 production (nearly 100% faradaic efficiency) and ultra-low charge-transfer resistance (0.96 Ω) in alkaline medium, which hold promise for practical applications. This work provides a powerful strategy for the facile production of fast nucleating MOF-derived electrodes with potential for industrial-scale application in energy storage and conversion. [ABSTRACT FROM AUTHOR]

Chitosan composite superfine fibers with a diameter of 321 ± 99 nm were prepared by electrospinning with PEO as the co-spinning polymer and itaconic acid as the in situ cross-linking agent. Itaconic acid was homogeneously dispersed in chitosan fibers and the in situ cross-linking endowed the prepared chitosan composite fibers with improved solvent resistance, thermostability and mechanical strength. Palladium species immobilized on these annealed chitosan fibers can efficiently catalyze the reduction reaction of 4-nitrophenol as well as the Mizoroki–Heck reaction of aromatic iodides with n-butyl acrylate in an aqueous medium. Furthermore, the larger fiber structure can facilitate the recovery and reuse of the palladium catalyst. The remarkable catalytic performance and easy recovery make this novel fiber-supported palladium catalyst hold great potential applications in green chemistry. [ABSTRACT FROM AUTHOR]

Developing advanced anode materials with multi-electron reaction, adequate charge transport, and suppressed volume changes is highly desirable in lithium storage. Both polyoxometalates (POMs) and metal–organic frameworks (MOFs) are attractive candidates for anode materials because of strong multi-electron redox properties of the former and high surface areas and controllable porosities of the latter. However, the easy dissolution of POMs in an electrolyte and the intrinsically poor conductivity of MOFs result in inferior rate performance and cycling capacity. In this paper, we skillfully encapsulate ionic liquids (ILs) into polyoxometalate-based metal–organic frameworks (POMOFs) to fabricate a series of ILs-functionalized POMOF crystals (denoted as POMs-ILs@MOFs), in which POMs are immobilized in MOF cages to avoid the leaching of POMs. Also, an enhanced conductivity is obtained by the modification of ILs. One of the POMs-ILs@MOFs crystals, PMo10V2-ILs@MIL-100, when used as the anode material, shows superior cycling stability and high rate capability, which is proven to be the best amongst those of all the reported MOF, POM, and POMOF crystal materials. The outstanding performances are attributed to the hybrid behavior of a battery and a supercapacitor, which results from the synergistic effects of ILs, POMs, and MOFs. Most importantly, we not only discover a series of new anode materials but also propose a new strategy to improve the conductivity of MOFs and POMOFs, which will guide the development of other electrode materials based on MOFs and POMOFs for lithium storage. [ABSTRACT FROM AUTHOR]

A novel polyoxometalate-based metal–organic framework (POMOF), [PMo8VMo4VIO37(OH)3Zn4][TPT]5·2TPT·2H2O (NNU-11, TPT = tris-(4-pyridyl)triazine), was synthesized. Zn-ε-Keggin fragments were directly connected with TPT ligands generating 2D layers and further interdigitated with each other by π–π stacking interactions to pack into a 3D array. The compound exhibited excellent stability in air and different organic solvents and even in different pH (pH 1–11) aqueous solutions. It can be utilized as an anode material for lithium ion batteries (LIBs) due to the combination of the multi-electron redox property of POM units and the functionalization of MOFs. NNU-11 exhibited a highly reversible capacity of 750 mA h g−1 at a current density of 50 mA g−1 after 200 cycles along with excellent cycle stability and rate performance. More importantly, for the first time, we designed and synthesized a POMOF crystalline structure model supported by π–π stacking interactions to demonstrate that intermolecular π–π stacking interactions are beneficial to promote the performance of LIBs. [ABSTRACT FROM AUTHOR]

A photoredox catalytic method was developed for the direct cyanation of alkyltrifluoroborates. This reaction provides a new and useful transformation of the easily available alkyltrifluoroborates. The photocatalytic reaction can tolerate a variety of functional groups with mild reaction conditions. Mechanistic investigations are consistent with the present reaction following a radical pathway. [ABSTRACT FROM AUTHOR]

The preparation, X-ray crystallography, EPR, magnetic and luminescent investigation of new metal-anion radical framework materials based on a new anion radical ligand generated by in situdeprotonation of a stable zwitterionic radical are described herein. N,O,N-tripodal anion radical ligand (bipo−) links metal cations, giving rise to four isostructural one-dimensional metal–organic frameworks, [M(bipo−)(L)]n[M = Zn, L = HCOO−(1), SCN−(1a), N3−(1b); M = Co, L = Br−(3)]. The tripodal bipo− ligand and one co-ligand, 1,4-benzenedicarboxylate, coordinate to metals leading to two isostructural two-dimensional metal–organic frameworks, [M(bipo−)(BDC)0.5]n[M = Zn (2) and Co (4)]. The two CoIIcompounds are the first examples that exhibit unusual ferromagnetic to antiferromagnetic phase transition with transition temperature over room temperature, which can be demonstrated by the cooling and warming measurements of susceptibility. Compound 4also exhibits long-range magnetic ordering with the critical temperature at about 44 K proved by ac susceptibility measurements. The metal-radical frameworks exhibit distinctly different fluorescence emissions. Especially, the isomorphous one-dimensional ZnIIcompounds show interesting terminal anion ligand-induced photoluminescent color changes, including direct and invariable white-light-emission with terminal SCN−ligand. [ABSTRACT FROM AUTHOR]

An efficient and recyclable ligand-free heterogeneous catalyst has been prepared by the immobilization of palladium onto ground pearl shell powders (Pd/shell powders, Pd/SP). The catalytic activity and recyclability of the prepared Pd/SP along with the charcoal and calcium carbonate supported palladium (Pd/C and Pd/CaCO3) catalysts have been evaluated using the reductive homocoupling of aromatic halides. Pd/SP not only has higher catalytic activity, but also exhibits much stronger stability than Pd/C and Pd/CaCO3. The remarkable Pd/SP stability has been attributed to the chelation of palladium species with the surface chitin and protein molecules of the supported pearl shell powders. The X-ray photoelectron spectroscopy (XPS) studies show that the reductive Pd0species can be regenerated in situfrom the oxidative Pd2+species for the Pd/SP catalyzed reductive homocoupling of aromatic halides in ethanol/DMSO solution, suggesting that the heterogeneous and homogeneous palladium catalysis proceeds through a similar Pd0/Pd2+cycle catalytic mechanism. [ABSTRACT FROM AUTHOR]

A stable zwitterionic radical can catalyze direct arylation of unactivated aromatic C–H bonds viaa chain homolytic aromatic substitution mechanism in the presence of potassium tert-butoxide. [ABSTRACT FROM AUTHOR]