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Enhancing the energy storage capacity of carbon electrodes is a key challenge to developing high-performance supercapacitors. In this study, we design an oxygen-enriched hierarchical nanoporous carbon electrode using laser fabrication and subsequent electrochemical activation, which demonstrates superior energy storage capacity. The carbon electrode is first obtained through the carbonization of phenolic resin under instantaneous high temperature induced by laser, resulting in multiple ion transport channels and a specific capacitance of 64.17 mF cm–2 at the current density of 0.2 mA cm–2. To further improve the performance, electrochemical activation is successfully conducted, leading to a 12.1-fold increase of the specific capacitance of the carbon electrodes. It is found that O–CO-containing functional groups formed during the activation process significantly contribute to the high capacitance enhancement. In a 1 M H2SO4 electrolyte, the activated hierarchical nanoporous carbon electrode delivers a high specific capacitance of 778.3 mF cm–2 under the same test conditions. Additionally, the abundant porous structure and excellent reversibility of redox reaction of the oxygen-containing functional groups enable the assembled supercapacitor to obtain a specific capacitance of 45.3 mF cm–2 at the current density of 0.4 mA cm–2 and maintain a capacitance retention rate of 93.6% after 10,000 charge–discharge tests. This study presents a strategy to prepare carbon electrode materials with both high performance and excellent stability. [ABSTRACT FROM AUTHOR]

A novel protocol for extending the scope of the Mitsunobu reaction to include amine nucleophiles to form C-N bonds through the utilization of N-heterocyclic phosphine-butane (NHP-butane) has been developed. Both aliphatic alcohols and benzyl alcohols are suitable substrates for C-N bond construction. Various acidic nucleophiles such as benzoic acids, phenols, thiophenol, and secondary sulfonamide also provide the desired products of esters, ethers, thioether, and tertiary sulfonamide with 43-93% yields. Importantly, C-N bond-containing pharmaceuticals, Piribedil and Cinnarizine, have been synthesized in one step from the commercial amines under this Mitsunobu reaction system. [ABSTRACT FROM AUTHOR]

The structural and electronic propertiesof MoS2/MoSe2bilayers are calculated usingfirst-principles methods. Itis found that the interlayer van der Waals interaction is not strongenough to form a lattice-matched coherent heterostructure. Instead,a nanometer-scale Moiré pattern structure will be formed. Byanalyzing the electronic structures of different stacking configurations,we predict that the valence-band maximum (VBM) state will come fromthe Γ point due to interlayer electronic coupling. This is confirmedby a direct calculation of a Moiré pattern supercell containing6630 atoms using the linear scaling three-dimensional fragment method.The VBM state is found to be strongly localized, while the conductionband minimum (CBM) state is only weakly localized, and it comes fromthe MoS2layer at the K point. We predict such wave functionlocalization can be a general feature for many two-dimensional (2D)van der Waals heterostructures and can have major impacts on the carriermobility and other electronic and optical properties. [ABSTRACT FROM AUTHOR]

We report the synthesis and characterizationof thienylenevinylene-baseddonor–acceptor alternating copolymers (PTVPhI-Eh and PTVPhI-C12)as highly efficient ambipolar semiconductors in a thin film transistor.These polymers exhibit significantly improved hole and electron mobilitiesafter thermal annealing. To determine the relationship between ambipolarcharge transport and thermal annealing, we investigated these polymersusing various analyses such as optical spectroscopy, Raman spectroscopy,computational quantum chemical calculation, X-ray diffraction, atomicforce microscopy, and ambipolar charge mobility measurements. In pristinefilms, the polymer chains exhibited weak intra- and interchain ordering.However, when samples were annealed at sufficiently high temperatures,they exhibited a more ordered intra- and interchain conformation.As a result, we found a strong relationship between intra- and interchainconformational changes of the polymers and corresponding ambipolarcharge transport properties during thermal annealing processes. Finally,we demonstrate complementary-like ambipolar inverters using a PTVPhI-Ehpolymer. The largely shifted inverting voltage was improved for thethermally annealed inverters, which exhibited large voltage gains(∼40). [ABSTRACT FROM AUTHOR]

We report that poly(l-lysine)-graft-poly(ethyleneglycol) (PLL-g-PEG) copolymers that bear multiplethiol groups on the polymer backbone are exceptional ligands for goldnanoparticles (AuNPs). In general, these graft copolymer ligands stabilizeAuNPs against environments that would ordinarily lead to particleaggregation. To characterize the effect of copolymer structure onAuNP stability, we synthesized thiolated PLL-g-PEGs(PLL-g-[PEG:SH]) with different backbone lengths,PEG grafting densities, and number of thiols per polymer chain. AuNPswere then combined with these polymer ligands, and the stabilitiesof the resulting AuNP@PLL-g-[PEG:SH] particles againsthigh temperature, oxidants, and competing thiol ligands were characterizedusing dynamic light scattering, visible absorption spectroscopy, andfluorescence spectrophotometry. Our observations indicate that thiolatedPLL-g-PEG ligands combine thermodynamic stabilizationvia multiple Au–S bonds and steric stabilization by PEG grafts,and the best graft copolymer ligands balance these two effects. Wehope that this new ligand system enables AuNPs to be applied to biotechnologicalapplications that require harsh experimental conditions. [ABSTRACT FROM AUTHOR]

The enantioselective synthesis of α,α-disubstituted cycloalkanones has been developed using a primary amine, thiourea-based dual catalysis pathway. A range of electrophiles and ring sizes are tolerated under the reaction conditions. A possible catalytic cycle is presented to explain the reactivity. [ABSTRACT FROM AUTHOR]

This study presents an investigation of the 2-butynyl alcohol···CO 2 adduct, combining pulsed jet Fourier transform microwave spectroscopy with quantum chemical calculations. Two distinct isomers have been observed in the pulsed jet with a relative population ratio of 3/2. It marks the first instance of microwave spectroscopic evidence, to the best of our knowledge, suggesting the existence of a C CO 2 ···π -C≡C- tetrel bond (π -C≡C- ···π* CO 2 interaction) in both observed isomers. This study highlights the importance of noncovalent interactions involving CO 2 in reactant complexes, paving the way for more efficient applications of CO 2 by understanding the physical basis of these noncovalent bonds.

In this work, we explore the use of ring-opening metathesis polymerization (ROMP) facilitated by a second-generation Grubbs catalyst (G2) for the development of advanced polymer membranes aimed at CO 2 separation. By employing a novel copolymer blend incorporating 4,4'-oxidianiline (ODA), 1,6-hexanediamine (HDA), 1-adamantylamine (AA), and 3,6,9-trioxaundecylamine (TA), along with a CO 2 -selective poly(ethylene glycol)/poly(propylene glycol) copolymer (Jeffamine2003) and polydimethylsiloxane (PDMS) units, we have synthesized membranes under ambient conditions with exceptional CO 2 separation capabilities. The strategic inclusion of PDMS, up to a 20% composition within the PEG/PPG matrix, has resulted in copolymer membranes that not only surpass the 2008 upper limit for CO 2 /N 2 separation but also meet the commercial targets for CO 2 /H 2 separation. Comprehensive analysis reveals that these membranes adhere to the mixing rule and exhibit percolation behavior across the entire range of compositions (0-100%), maintaining robust antiplasticization performance even under pressures up to 20 atm. Our findings underscore the potential of ROMP in creating precisely engineered membranes for efficient CO 2 separation, paving the way for their application in large-scale environmental and industrial processes.

Single-crystal semiconductor-based photocatalysts exposing unique crystallographic facets show promising applications in energy and environmental technologies; however, crystal facet engineering through solid-state synthesis for photocatalytic overall water splitting is still challenging. Herein, we develop a novel crystal facet engineering strategy through solid-state recrystallization to synthesize uniform SrTiO 3 single crystals exposing tailored {111} facets. The presynthesized low-crystalline SrTiO 3 precursors enable the formation of well-defined single crystals through kinetically improved crystal structure transformation during solid-state recrystallization process. By employing subtle Al 3+ ions as surface morphology modulators, the crystal surface orientation can be precisely tuned to a controlled percentage of {111} facets. The photocatalytic overall water splitting activity increases with the exposure percentage of {111} facets. Owing to the outstanding crystallinity and favorable anisotropic surface structure, the SrTiO 3 single crystals with 36.6% of {111} facets lead to a 3-fold enhancement of photocatalytic hydrogen evolution rates up to 1.55 mmol·h -1 in a stoichiometric ratio of 2:1 than thermodynamically stable SrTiO 3 enclosed with isotropic {100} facets.

In this work, the band structure of CsCd x Pb 1- x Br 3 alloys is investigated through first-principles calculations. An unusual upward band gap bowing is revealed, which is consistent with the experimental observations of the blue-shifted gap in Cd doped CsPbBr 3 . The gap bowing is found to be mainly contributed to by the conduction band minimum. Based on symmetry analysis, it is demonstrated that, at the Pb-rich or Cd-rich regime, the hybridization between the Pb(6p)-driven and Cd(5s)-driven conduction bands is strongly suppressed due to their different symmetries. Such a chemical mismatch leads to an almost independent evolution of the Pb(6p) and Cd(5s) bands. Then, a model of band shrinking and broadening is proposed to explain upward gap bowing. The results highlight the critical role of symmetry in determining the electronic properties of alloys consisting of materials with distinct band edge characters.

Efficient charge injection/extraction from/to contact electrodes is essential to realize organic electronic and optoelectronic devices with optimum characteristics for many applications. Herein, we studied a versatile reductive interlayer based on sodium borohydride (NaBH 4 ) to control the contact properties of the staggered organic field-effect transistors (OFETs) either by doping and/or by regulating the contribution of charge carriers. The versatile functionalities of the NaBH 4 layer are mainly determined by the alignment of frontier molecular orbitals of donor-acceptor (D-A) type copolymer semiconductors and the work function of the contact electrode. After incorporating the NaBH 4 layer, the work function of the bottom-contact gold electrode can be decreased significantly by 1.0 eV, which makes it favorable to efficient electron injection. An Ohmic contact is achieved by the spontaneous injection of electrons to the n-type organic semiconductors with high electron affinity while converting the OFET operation mode to n-type characteristics by blocking the counter-charge carriers for the other types of ambipolar and p-type semiconductors. The solution-processed reducing agent can be a valuable approach to develop high-performance printed and flexible electronic devices through careful engineering to obtain proper contributions of charge carriers either as electrons or holes in various D-A copolymer semiconductors.

For the biomedical application of engineered bacteria, strictly regulating the function of engineered bacteria has always been the goal pursued. However, the existing regulation methods do not meet the needs of the in vivo application of engineered bacteria. Therefore, the exploration of the precise regulation of engineered bacteria is necessary. Herein, heat-sensitive engineered bacteria that can respond to thermal stimuli within 30 min were constructed, and the precise control of functions was verified in the intestines of various model organisms (including C. elegans , bees, and mice). Subsequently, heat-sensitive engineered bacteria were shown to colonize the mouse tumor microenvironment. Finally, thermal stimulation was proven to control engineered bacteria to produce the therapeutic protein tumor necrosis factor α (TNF-α) in the tumor. After three heat stimulation treatments, the growth of the tumor was significantly inhibited, suggesting that heat can be used as a strategy to precisely control engineered bacteria in vivo .

Circularly polarized light (CPL) is an inherently chiral entity and is considered one of the possible deterministic signals that led to the evolution of homochirality. While accumulating examples indicate that chirality beyond the molecular level can be induced by CPL, not much is yet known about circumstances where the spin angular momentum of light competes with existing molecular chiral information during the chirality induction and amplification processes. Here we present a light-triggered supramolecular polymerization system where chiral information can both be transmitted and nonlinearly amplified in a "sergeants-and-soldiers" manner. While matching handedness with CPL resulted in further amplification, we determined that opposite handedness could override molecular information at the supramolecular level when the enantiomeric excess was low. The presence of a critical chiral bias suggests a bifurcation point in the homochirality evolution under random external chiral perturbation. Our results also highlight opportunities for the orthogonal control of supramolecular chirality decoupled from molecular chirality preexisting in the system.

With the development of technology, adjuvant immunotherapy has become a promising strategy for prevention of postoperative tumor regression and metastasis by stimulating the host immune response. However, the therapeutic effects are still unsatisfactory due to the lack of synergy between different methods. In this study, an efficient synergistic immunotherapy system based on injectable sodium alginate hydrogels was designed to inhibit in situ recurrence and metastasis at the same time. On the one hand, an injectable sodium alginate (SA) hydrogel microsystem loaded with toll-like receptor (TLR) agonists (CpG ODNs) was synthesized for inhibiting in situ recurrence, and then carcinoembryonic antigen (CEA) probe was also added to detect CEA based on fluorescence resonance energy transfer (FRET) technology to monitor the occurrence and development of tumor recurrence. On the other hand, an anti-programmed cell death 1 ligand 1 antibody (anti-PD-L1)-modified SA nanogel loaded with indocyanine green (ICG@SA-anti-PD-L1 nanogel) was prepared for diagnosing and inhibiting lung metastasis by assisting orthotopic tumor therapy. In vitro and in vivo results demonstrated that this SA micro/nanosystem could monitor and inhibit postoperative recurrence and metastasis. We hope that this micro/nano-synergistic system will become an effective strategy for postoperative adjuvant immunotherapy.

Cell-free DNA (cfDNA) analysis, specifically circulating tumor DNA (ctDNA) analysis, provides enormous opportunities for noninvasive early assessment of cancers. To date, PCR-based methods have led this field. However, the limited sensitivity/specificity of PCR-based methods necessitates the search for new methods. Here, we describe a direct approach to detect KRAS G12D mutated genes in clinical ctDNA samples with the utmost LOD and sensitivity/specificity. In this study, MutS protein was immobilized on the tip of an atomic force microscope (AFM), and the protein sensed the mismatched sites of the duplex formed between the capture probe on the surface and mutated DNA. A noteworthy LOD (3 copies, 0.006% allele frequency) was achieved, along with superb sensitivity/specificity (100%/100%). These observations demonstrate that force-based AFM, in combination with the protein found in nature and properly designed capture probes/blockers, represents an exciting new avenue for ctDNA analysis.

Herein, we have reported a nickel-catalyzed cascade reductive thiolation of aryl halides with sulfinates driven by paired electrolysis. This protocol uses sulfinates as the sulfur source, and various thioethers could be synthesized under mild conditions. By mechanism exploration, we find that a cascade chemical step is allowed on the electrode interface and could alter the reaction pathway in paired electrolysis, whose findings could help the discovery of novel cascade reactions with unique reactivity.

Understanding the carrier transport mechanism in transition metal dichalcogenides (TMDs) is essential for their device application. Experiments demonstrated that at low carrier density and room temperature, the conductivity in TMDs is dominant by activation hopping transport through localized S-vacancy states. In this work, a multiscale model combining ab initio calculation and the Marcus theory is applied to study such transport. We identify phonon-assisted hopping (PAH) as the most possible mechanism for the activation hopping. It is found that the macroscopic conductivity is mainly contributed by a few microscopic percolation paths. Analysis on the hopping distance indicates nearest-neighbor hopping behavior. The dependence of PAH mobility on defect concentration, temperature, and energy mismatch between defect sites is discussed. It is shown that all these factors can strongly affect the mobility. We further proposed that alloying can be an efficient way to tune the mobility due to increased energy mismatch effect.