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Probing biomolecular interactions at cellular interfaces is crucial for understanding and interfering with life processes. Although affinity binders with site specificity for membrane proteins are unparalleled molecular tools, a high demand remains for novel multi‐functional ligands. In this study, a synthetic peptide (APQQ) with tight and specific binding to the untargeted extracellular loop of CD81 evolved from a genetically encoded peptide pool. With tailored affinity, APQQ flexibly accesses, site‐specifically binds, and forms a complex with CD81, enabling in‐situ tracking of the dynamics and activity of this protein in living cells, which has rarely been explored because of the lack of ligands. Furthermore, APQQ triggers the relocalization of CD81 from diffuse to densely clustered at cell junctions and modulates the interplay of membrane proteins at cellular interfaces. Motivated by these, efficient suppression of cancer cell migration, and inhibition of breast cancer metastasis were achieved in vivo. [ABSTRACT FROM AUTHOR]

Work function strongly impacts the surficial charge distribution, especially for metal‐support electrocatalysts when a built‐in electric field (BEF) is constructed. Therefore, studying the correlation between work function and BEF is crucial for understanding the intrinsic reaction mechanism. Herein, we present a Pt@CoOx electrocatalyst with a large work function difference (ΔΦ) and strong BEF, which shows outstanding hydrogen evolution activity in a neutral medium with a 4.5‐fold mass activity higher than 20 % Pt/C. Both experimental and theoretical results confirm the interfacial charge redistribution induced by the strong BEF, thus subtly optimizing hydrogen and hydroxide adsorption energy. This work not only provides fresh insights into the neutral hydrogen evolution mechanism but also proposes new design principles toward efficient electrocatalysts for hydrogen production in a neutral medium. [ABSTRACT FROM AUTHOR]

The atomically precise control over the size, shape and structure of nanographenes (NGs) or the introduction of heteroatom dopants into their sp2‐carbon lattice confer them valuable electronic, optical and magnetic properties. Herein, we report on the design and synthesis of a hexabenzocoronene derivative embedded with graphitic nitrogen in its honeycomb lattice, achieved via on‐surface assisted cyclodehydrogenation on the Au(111) surface. Combined scanning tunnelling microscopy/spectroscopy and non‐contact atomic force microscopy investigations unveil the chemical and electronic structures of the obtained dicationic NG. Kelvin probe force microscopy measurements reveal a considerable variation of the local contact potential difference toward lower values with respect to the gold surface, indicative of its positive net charge. Altogether, we introduce the concept of cationic nitrogen doping of NGs on surfaces, opening new avenues for the design of novel carbon nanostructures. [ABSTRACT FROM AUTHOR]

The introduction of heteroatoms is one of the most important ways to modulate the intrinsic electronic structure of electrocatalysts to improve their catalytic activity. However, for transition metal chalcogenides with highly symmetric crystal structure (HS‐TMC), the introduction of heteroatoms, especially those with large atomic radius, often induces large lattice distortion and vacancy defects, which may lead to structural phase transition of doped materials or structural phase reconstruction during the catalytic reaction. Such unpredictable situations will make it difficult to explore the connection between the intrinsic electronic structure of doped catalysts and catalytic activity. Herein, taking thermodynamically stable cubic CoSe2 phase as an example, we demonstrate that nitrogen incorporation can effectively regulate the intrinsic electronic structure of HS‐TMC with structural phase stability and thus promote its electrocatalytic activity for the hydrogen evolution activity (HER). In contrast, the introduction of phosphorus can lead to structural phase transition from cubic CoSe2 to orthorhombic phase, and the structural phase of phosphorus‐doped CoSe2 is unstable for HER. [ABSTRACT FROM AUTHOR]

The catalytic activity of metal clusters is closely related with the support; however, knowledge on the influence of the support on the catalytic activity is scarce. We demonstrate that Pt nanoclusters (NCs) anchored on porous TiO2 nanosheets with rich oxygen vacancies (VO‐rich Pt/TiO2) and deficient oxygen vacancies (VO‐deficient Pt/TiO2), display significantly different catalytic activity for the hydrogen evolution reaction (HER), in which VO‐rich Pt/TiO2 shows a mass activity of 45.28 A mgPt−1 at −0.1 V vs. RHE, which is 16.7 and 58.8 times higher than those of VO‐deficient Pt/TiO2 and commercial Pt/C, respectively. DFT calculations and in situ Raman spectra suggest that porous TiO2 with rich oxygen vacancies can simultaneously achieve reversed charge transfer (electrons transfer from TiO2 to Pt NCs) and enhanced hydrogen spillover from Pt NCs to the TiO2 support, which leads to electron‐rich Pt NCs being amenable to proton reduction of absorbed H*, as well as the acceleration of hydrogen desorption at Pt catalytic sites—both promoting the HER. Our work provides a new strategy for rational design of highly efficient HER catalysts. [ABSTRACT FROM AUTHOR]

Arylation of carbonyls, one of the most common approaches toward alcohols, has received tremendous attention, as alcohols are important feedstocks and building blocks in organic synthesis. Despite great progress, there is still a great gap to develop an ideal arylation method featuring mild conditions, good functional group tolerance, and readily available starting materials. We now show that electrochemical arylation can fill the gap. By taking advantage of synthetic electrochemistry, commercially available aldehydes (ketones) and benzylic alcohols can be readily arylated to provide a general and scalable access to structurally diverse alcohols (97 examples, >10 gram‐scale). More importantly, convergent paired electrolysis, the ideal but challenging electrochemical technology, was employed to transform low‐value alcohols into more useful alcohols. Detailed mechanism study suggests that two plausible pathways are involved in the redox neutral α‐arylation of benzylic alcohols. [ABSTRACT FROM AUTHOR]

Herein, we report the design and synthesis of a series of novel cationic nitrogen-doped nanographenes (CNDNs) with nonplanar geometry and axial chirality. Single-crystal X-ray analysis reveals helical and cove-edged structures. Compared to their all-carbon analogues, the frontier orbitals of the CNDNs are energetically lower lying, with a reduced optical energy gap and greater electron-accepting behavior. Cyclic voltammetry shows all the derivatives to undergo quasireversible reductions. In situ spectroelectrochemical studies prove that, depending on the number of nitrogen dopants, either neutral radicals (one nitrogen dopant) or radical cations (two nitrogen dopants) are formed upon reduction. The concept of cationic nitrogen doping and introducing helicity into nanographenes paves the way for the design and synthesis of expanded nanographenes or even graphene nanoribbons with cationic nitrogen dopants. [ABSTRACT FROM AUTHOR]

The electrocatalyzed oxygen reduction and evolution reactions (ORR and OER, respectively) are the core components of many energy conversion systems, including water splitting, fuel cells, and metal-air batteries. Rational design of highly efficient non-noble materials as bifunctional ORR/OER electrocatalysts is of great importance for large-scale practical applications. A new strongly coupled hybrid material is presented, which comprises CoO x nanoparticles rich in oxygen vacancies grown on B,N-decorated graphene (CoO x NPs/BNG) and operates as an efficient bifunctional OER/ORR electrocatalyst. Advanced spectroscopic techniques were used to confirm formation of abundant oxygen vacancies and strong Co−N−C bridging bonds within the CoO x NPs/BNG hybrid. Surprisingly, the CoO x NPs/BNG hybrid electrocatalyst is highly efficient for the OER with a low overpotential and Tafel slope, and is active in the ORR with a positive half-wave potential and high limiting current density in alkaline medium. [ABSTRACT FROM AUTHOR]

Rational design of non-noble materials as highly efficient, economical, and durable bifunctional catalysts for oxygen evolution and reduction reactions (OER/ORR) is currently a critical obstacle for rechargeable metal-air batteries. A new route involving S was developed to achieve atomic dispersion of Fe-N x species on N and S co-decorated hierarchical carbon layers, resulting in single-atom bifunctional OER/ORR catalysts for the first time. The abundant atomically dispersed Fe-N x species are highly catalytically active, the hierarchical structure offers more opportunities for active sites, and the electrical conductivity is greatly improved. The obtained electrocatalyst exhibits higher limiting current density and a more positive half-wave potential for ORR, as well as a lower overpotential for OER under alkaline conditions. Moreover, a rechargeable Zn-air battery device comprising this hybrid catalyst shows superior performance compared to Pt/C catalyst. This work will open a new avenue to design advanced bifunctional catalysts for reversible energy storage and conversion devices. [ABSTRACT FROM AUTHOR]

Developing highly active catalysts for the oxygen evolution reaction (OER) is of paramount importance for designing various renewable energy storage and conversion devices. Herein, we report the synthesis of a category of Co-Pi analogue, namely cobalt-based borate (Co-Bi) ultrathin nanosheets/graphene hybrid by a room-temperature synthesis approach. Benefiting from the high surface active sites exposure yield, enhanced electron transfer capacity, and strong synergetic coupled effect, this Co-Bi NS/G hybrid shows high catalytic activity with current density of 10 mA cm−2 at overpotential of 290 mV and Tafel slope of 53 mV dec−1 in alkaline medium. Moreover, Co-Bi NS/G electrocatalysts also exhibit promising performance under neutral conditions, with a low onset potential of 235 mV and high current density of 14.4 mA cm−2 at 1.8 V, which is the best OER performance among well-developed Co-based OER electrocatalysts to date. Our finding paves a way to develop highly active OER electrocatalysts. [ABSTRACT FROM AUTHOR]

Inorganic nanowire arrays hold great promise for next-generation energy storage and conversion devices. Understanding the growth mechanism of nanowire arrays is of considerable interest for expanding the range of applications. Herein, we report the solution-liquid-solid (SLS) synthesis of hexagonal nickel selenide nanowires by using a nonmetal molecular crystal (selenium) as catalyst, which successfully brings SLS into the realm of conventional low-temperature solution synthesis. As a proof-of-concept application, the NiSe nanowire array was used as a catalyst for electrochemical water oxidation. This approach offers a new possibility to design arrays of inorganic nanowires. [ABSTRACT FROM AUTHOR]

Designing highly efficient electrocatalysts for oxygen evolution reaction (OER) plays a key role in the development of various renewable energy storage and conversion devices. In this work, we developed metallic Co4N porous nanowire arrays directly grown on flexible substrates as highly active OER electrocatalysts for the first time. Benefiting from the collaborative advantages of metallic character, 1D porous nanowire arrays, and unique 3D electrode configuration, surface oxidation activated Co4N porous nanowire arrays/carbon cloth achieved an extremely small overpotential of 257 mV at a current density of 10 mA cm-2, and a low Tafel slope of 44 mVdec-1 in an alkaline medium, which is the best OER performance among reported Co-based electrocatalysts to date. Moreover, in-depth mechanistic investigations demonstrate the active phases are the metallic Co4N core inside with a thin cobalt oxides/hydroxides shell during the OER process. Our finding introduces a new concept to explore the design of highefficiency OER electrocatalysts. [ABSTRACT FROM AUTHOR]

The rhodium-catalyzed asymmetric N-selective coupling of pyrazole derivatives with terminal allenes gives access to enantioenriched secondary and tertiary allylic pyrazoles, which can be employed for the synthesis of medicinally important targets. The reaction tolerates a large variety of functional groups and labelling experiments gave insights into the reaction mechanism. This new methodology was further applied in a highly efficient synthesis of JAK 1/2 inhibitor ( R)-ruxolitinib. [ABSTRACT FROM AUTHOR]

The rhodium-catalyzed, highly N2- and N1-selective coupling of benzotriazoles with allenes is reported. The exceptionally high N2 and N1 selectivities were achieved by using a rhodium(I)/DPEphos and rhodium(I)/JoSPOphos catalyst, respectively. This method permits the atom-economic synthesis of valuable branched N2- and N1-allylated benzotriazole derivatives and allows for preliminary studies of their reactivity. [ABSTRACT FROM AUTHOR]

New Rh- and Pd-catalyzed regiodivergent and stereoselective intermolecular coupling reactions of imidazole derivatives with mono-substituted allenes are herein reported. Using a RhI/Josiphos system, perfect regioselectivities and high enantiomeric excess were obtained, while a PdII/dppf system gave linear products with high regioselectivities and high E/ Z selectivities. This method permits the atom economic synthesis of valuable branched and linear allylic imidazole derivatives. [ABSTRACT FROM AUTHOR]

A new metallic 2D material with high electrical conductivity (1×103 S m−1) consists of VSe2 ultrathin nanosheets with 4–8 Se‐V‐Se atomic layers. This is the first 2D transition‐metal dichalcogenide with intrinsic room‐temperature ferromagnetism. The nanosheets increase the charge‐density‐wave transition temperature to 135 K by dimensional reduction. [ABSTRACT FROM AUTHOR]