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Wearable thermoelectric (TE) materials are seen as excellent candidates for flexible electronics because of their unique self-powered properties, multistimulus sensing and human waste heat conversion. However, currently reported flexible TE materials still face challenges such as poor durability, uncomfortable wearing and sensing signals crosstalking each other. Herein, this study describes a hot-air cross-linking method for the preparation of multifunctional TE fabrics with enhanced durability. Poly(ethylene terephthalate) (PET) fibers with core and sheath structures having different melting points were selected as flexible substrates. Poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOT:PSS) and single-walled carbon nanotubes (SWCNTs) were embedded stably on the surface of the sheath layer in the presence of heat treatment. The fiber-welded structure created by thermal cross-linking improves the durability of TE fabrics, including consistent mechanical and electrical properties after a 6 h wash test and 6000 compression cycles. The unique fiber structure of TE fabrics ensures excellent breathability (313.7 mm s -1 at 200 Pa), which meets the breathability requirements for human wear. In addition, the fiber-prepared sensors have excellent compressive strain response (20 ms response time and 30 ms recovery time) and precise temperature discrimination (0.17 K minimum discrimination temperature) for accurate real-time monitoring of the sensed signals. Thus, the TE fabrics can be used for human motion recognition, including pulse monitoring, sign language expression, and motions in joint areas. Moreover, the fabricated wearable TE device is connected to a Bluetooth module for wireless transmission, which can be used for mechanical and temperature sensing of the robot arm without signals crosstalking. This new durable TE fabric paves the way for the next generation of smart wearable technology.

Coinage-metal clusters with excellent luminescence properties have attracted considerable interest due to their intriguing structures and potential applications. However, achieving strong near-infrared (NIR) luminescence in these clusters is highly challenging. Here, we have successfully synthesized the first Ln III /Cu I bimetallic clusters, formulated as [LnCu 54 O 6 Cl 3 (2-MeO-PhC≡C) 36 ] (ClO 4 ) 6 (Ln = Yb for YbCu 54 , Er for ErCu 54 , and Gd for GdCu 54 ). Single crystal X-ray diffraction showed that the LnCu 54 clusters have a three-layered core-shell structure, consisting of (LnO 6 )@Cu 18 Cl 3 @Cu 36 units protected by 36 2-MeO-PhC≡C - ligands. Notably, the YbCu 54 cluster exhibits significant NIR-II luminescence at 986 nm with the solid quantum efficiency of 33.3%, the highest among Cu clusters with NIR-II emission. This work not only reports the first category of Ln III /Cu I clusters but also presents a method to enhance NIR luminescence in coinage-metal clusters through the incorporation of Ln III ions.

Graphite exhibits crystal anisotropy, which impedes the mass transfer of ion intercalation and extraction processes in Li-ion batteries. Herein, a dual-shock chemical strategy has been developed to synthesize the carbon anode. This approach comprised two key phases: (1) a thermal shock utilizing ultrahigh temperature (3228 K) can thermodynamically facilitate graphitization; (2) a mechanical shock (21.64 MPa) disrupting the π-π interactions in the aromatic chains of carbon can result in hybrid-structured carbon composed of crystalline and amorphous carbon. The optimized carbon (DSC-200-0.3) demonstrates a capacity of 208.61 mAh/g at a 10C rate, with a significant enhancement comparing with 15 mAh/g of the original graphite. Impressively, it maintains 81.06% capacity even after 3000 charge-discharge cycles. Dynamic process analysis reveals that this superior rate performance is attributed to a larger interlayer spacing facilitating ion transport comparing with the original graphite, disordered amorphous carbon for additional lithium storage sites, and crystallized carbon for enhanced charge transfer. The dual-shock chemical approach offers a cost-effective and efficient method to rapidly produce hybrid-structured carbon anodes, enabling 10C fast charging capabilities in lithium-ion batteries.

The coupled relationship between carrier and phonon scattering severely limits the thermoelectric performance of n-type GeTe materials. Here, we provide an efficient strategy to enlarge grains and induce vacancy clusters for decoupling carrier-phonon scattering through the annealing optimization of n-type GeTe-based materials. Specifically, boundary migration is used to enlarge grains by optimizing the annealing time, while vacancy clusters are induced through the aggregation of Ge vacancies during annealing. Such enlarged grains can weaken carrier scattering, while vacancy clusters can strengthen phonon scattering, leading to decoupled carrier-phonon scattering. As a result, a ratio between carrier mobility and lattice thermal conductivity of ∼492.8 cm 3 V -1 s -1 W -1 K and a peak ZT of ∼0.4 at 473 K are achieved in Ge 0.67 Pb 0.13 Bi 0.2 Te. This work reveals the critical roles of enlarged grains and induced vacancy clusters in decoupling carrier-phonon scattering and demonstrates the viability of fabricating high-performance n-type GeTe materials via annealing optimization.

Incorporating donor doping into Mg 3 Sb 1.5 Bi 0.5 to achieve n-type conductivity is one of the crucial strategies for performance enhancement. In pursuit of higher thermoelectric performance, we herein report co-doping with Te and Y to optimize the thermoelectric properties of Mg 3 Sb 1.5 Bi 0.5 , achieving a peak ZT exceeding 1.7 at 703 K in Y 0.01 Mg 3.19 Sb 1.5 Bi 0.47 Te 0.03 . Guided by first-principles calculations for compositional design, we find that Te-doping shifts the Fermi level into the conduction band, resulting in n-type semiconductor behavior, while Y-doping further shifts the Fermi level into the conduction band and reduces the bandgap, leading to enhanced thermoelectric performance with a power factor as high as >20 μW cm -1 K -2 . Additionally, through detailed micro/nanostructure characterizations, we discover that Te and Y co-doping induces dense crystal and lattice defects, including local lattice distortions and strains caused by point defects, and densely distributed grain boundaries between nanocrystalline domains. These defects efficiently scatter phonons of various wavelengths, resulting in a low thermal conductivity of 0.83 W m -1 K -1 and ultimately achieving a high ZT . Furthermore, the dense lattice defects induced by co-doping can further strengthen the mechanical performance, which is crucial for its service in devices. This work provides guidance for the composition and structure design of thermoelectric materials.

Pyrroloindoline is a privileged heterocyclic motif that is widely present in many natural products and pharmaceutical compounds. Herein, we report an amidyl radical-mediated dearomatization for synthesizing a series of pyrroloindolines via N-heterocyclic carbene catalysis. In this organocatalytic process, the Breslow enolate served as both a single electron donor and an acyl radical equivalent to assemble C3a-acyl pyrroloindolines with a broad substrate scope. Sequential reduction of the indole derivatives provided the analogues of (±)-desoxyeseroline, which exhibited potential anticancer activity.

We, for the first time, disclosed a simple and efficient strategy for the late-stage functionalization of primary sulfonamides by diazotization, leading to sulfonyl chlorides, sulfonates, and complex sulfonamides. This protocol obviates the requirement for the prefunctionalization of sulfonamides. Its applicability is exemplified by the late-stage functionalization of sulfonamide-type drugs.

Hepatocellular carcinoma (HCC) is one of the main principal causes of cancer death, and the late definite diagnosis limits therapeutic approaches in time. The early diagnosis of HCC is essential, and the previous investigations on the biomarkers inferred that the γ-glutamyltranspeptidase (GGT) level could indicate the HCC process. Herein, a near-infrared fluorescence/photoacoustic (NIRF/PA) bimodal probe, CySO 3 -GGT , was developed for monitoring the GGT level and thus to image the HCC process. After the in-solution tests, the bimodal response was convinced. The various HCC processes were imaged by CySO 3 -GGT at the cellular level. Then, the CCl 4 -induced HCC (both induction and treatment) and the subcutaneous and orthotopic xenograft mice models were selected. All throughout the tests, CySO 3 -GGT achieved NIRF and PA bimodal imaging of the HCC process. In particular, CySO 3 -GGT could effectively realize 3D imaging of the HCC nodule by visualizing the boundary between the tumor and the normal tissue. The information here might offer significant guidance for the dynamic monitoring of HCC in the near future.

With the development of wearable electronics, inorganic flexible thin films (f-TFs) with high thermoelectric performance have attracted increasing research interest. To further enhance the thermoelectric performance of p-type inorganic Sb 2 Te 3 -based f-TFs, we employed direct current treatment to tune the crystallinity by rationally tuning the direct current treatment time. Correspondingly, a high electrical conductivity of >845 S cm -1 and a moderate Seebeck coefficient of >110 μV K -1 within the entire measurement temperature range have been simultaneously achieved. Consequently, a high power factor of 12.84 μW cm -1 K -2 at 423 K has been realized in the as-prepared p-type Sb 2 Te 3 f-TF treated by a direct current of 5 A for 4 min. A flexible thermoelectric device has been further assembled to demonstrate the power-generating capacity. This study indicates that the direct current treatment is an effective method to improve the thermoelectric performance of Sb 2 Te 3 f-TFs.

The construction of silicon-containing molecules has received increasing attention in recent years. Herein, we report the generation of silyl radicals through NHC catalysis under mild reaction conditions. This methodology offers a novel and convenient route to a diverse range of β-silyl ketones with a broad substrate scope and good functional group compatibility. Both the radical clock and electrochemical studies are consistent with the hypothesis of ground-state SET, and a plausible mechanism for the organocatalytic transformation is proposed.

Chiral metal nanoclusters have recently been attracting great attention. It is challenging to realize asymmetric catalysis via atomically precise metal nanoclusters. Herein, we report the synthesis and total structure determination of chiral clusters [Au 7 Ag 8 (dppf) 3 (l-/d-proline) 6 ](BF 4 ) 2 ( l -/d-Au 7 Ag 8 ). Superatomic clusters l-/d-Au 7 Ag 8 display intense and mirror-image Cotton effects in their CD spectra. Density functional theory (DFT) calculations were carried out to understand the correlation between electronic structures and the optical activity of the enantiomeric pair. Surprisingly, the incorporation of proline in a metal nanocluster can significantly promote the catalytic efficiency in asymmetric Aldol reactions. The increase of catalytic activity of Au 7 Ag 8 in comparison with organocatalysis by proline is attributed to the cooperative effect of the metal core and prolines, showing the advantages of the integration of metal catalysis and organocatalysis in a metal nanocluster.

There have been significant advancements in radical-mediated reactions through covalent-based organocatalysis. Here, we present the generation of iminyl and amidyl radicals via N-heterocyclic carbene (NHC) catalysis, enabling diastereoselective aminoacylation of trisubstituted alkenes. Different from photoredox catalysis, single electron transfer from the deprotonated Breslow intermediate to O -aryl hydroxylamine generates an NHC-bound ketyl radical, which undergoes diastereocontrolled cross-coupling with the prochiral C-centered radical. This operationally simple method provides a straightforward access to a variety of pyrroline and oxazolidinone heterocycles with vicinal stereocenters (77 examples, up to >19:1 d.r.). Electrochemical studies of the acyl thiazolium salts support our reaction design and highlight the reducing ability of Breslow-type derivatives. A detailed computational analysis of this organocatalytic system suggests that radical-radical coupling is the rate-determining step, in which π-π stacking interaction between the radical intermediates subtly controls the diastereoselectivity.

A series of acetylacetone-protected lanthanide-titanium-oxo clusters (LTOCs), formulated as [La 6 Ti(μ 3 -OH) 8 (acac) 12 (CH 3 O) 2 (CH 3 OH) 6 ] ( La 6 Ti ; Hacac = acetylacetone) and [Ln 9 Ti 2 (μ 4 -O)(μ 3 -OH) 14 (acac) 17 (CH 3 O) 2 (CH 3 OH) 3 ] [Ln = Eu ( Eu 9 Ti 2 ) and Tb ( Tb 9 Ti 2 )], were synthesized through the reactions of LnCl 3 ·6H 2 O (Ln = La, Eu, and Tb), Hacac, Ti(O i Pr) 4 , and triethylamine in methanol. Crystal structural analysis shows that La 6 Ti exhibits an hourglass-like structure consisting of two La 3 Ti cubane subunits by sharing one Ti 4+ ion, while Eu 9 Ti 2 can be viewed as a combination of four Eu 3 Ti cubane subunits by sharing three corners and one side. The photoluminescence (PL) measurements show that Tb 9 Ti 2 exhibits excellent PL properties with a high quantum yield (QY) of 34.8%, while Eu 9 Ti 2 only has a QY of 1.4% because of the different photosensitizations of ligands to Eu 3+ and Tb 3+ ions in the photophysical process.

The understanding of the hydrolysis mechanism of lanthanide ions is limited by their elusive coordination configuration and undeveloped technology. A potential solution by high-resolution mass spectroscopy studies is hindered by the lack of a stable model under electrospray ionization (ESI) conditions and the complexity of the spectra. Herein, it is demonstrated that diketonate ligands can efficiently stabilize the hydrolyzed intermediate cluster of Ln 3+ under ESI conditions, and an effective mass difference fingerprint of isomorphism (MDFI) method is proposed, which can allow the determination of the nuclearity-number of the species without depth resolution. Thus, the hydrolysis of Ln 3+ into an atomically precise hydroxide cluster is observed at the level of precise formulae. The species evolution upon hydrolysis is along the dominant path of {Eu 3 }-{Eu 4 }-{Eu 9 }-{Eu 10 }-{Eu 11 }-{Eu 15 }-{Eu 16 } and a nondominant path of {Eu 3 }-{Eu 4 }-{Eu 8 -1}-{Eu 8 -2} under the investigated conditions. The crystal of the {Eu 16 } species was obtained via low-temperature crystallization, and single-crystal X-ray diffraction studies show that its structure contains three octahedral {o-Ln 6 } units. The contradiction between multiple {o-Ln 6 } units in the structure and the absence in the formation process indicates that the repetitive subunit observed in the structure does not necessarily correspond to the construction units of high-nuclearity clusters. Photophysical measurements indicate that Eu 16 cluster has a high total emission quantum efficacy of 12.8% in the solid state. This study provides fundamental insights into the formation, evolution, and assembly of small lanthanide hydroxide units upon hydrolysis, which is vital for the goal of directional synthesis of lanthanide hydroxide clusters.

Flexible thermoelectric materials and devices show great potential to solve the energy crisis but still face great challenges of high cost, complex fabrication, and tedious postprocessing. Searching for abnormal thermoelectric materials with rapid and scale-up production can significantly accelerate their applications. Here, we develop superlarge 25 × 20 cm 2 commercial graphite-produced composite films in batches, achieved by a standard 10 min industrial process. The high cost effectiveness ( S 2 σ/cost) of 7250 μW g m -1 K -2 $ -1 is absolutely ahead of that of the existing thermoelectric materials. The optimized composite film shows a high power factor of 94 μW m -1 K -2 at 150 °C, representing the optimal value of normal carbon materials so far. Furthermore, we design two types of flexible thermoelectric devices fabricated based on such a novel composite, which achieve an output open-circuit voltage of 3.70 mV using the human wrist as the heat source and 1.33 mV soaking in river water as the cold source. Our study provides distinguished inspiration to enrich flexible and cost-effective thermoelectric materials with industrial production.

Thermoelectric properties of CoSb 3 -based skutterudites are greatly determined by the removal of detrimental impurities, such as (Fe/Co)Sb 2 , (Fe/Co)Sb, and Sb. In this study, we use a facile temperature gradient zone melting (TGZM) method to synthesize high-performance CoSb 3 -based skutterudites by impurity removal. After removing metallic or semimetallic impurities (Fe/Co)Sb, (Fe/Co)Sb 2 , and Sb, the carrier concentration of TGZM-Ce 0.75 Fe 3 CoSb 12 can be reduced to 1.21 × 10 20 cm -3 and the electronic thermal conductivity dramatically reduced to 0.7 W m -1 K -1 at 693 K. Additionally, removing these impurities also effectively reduces the lattice thermal conductivity from 7.2 W m -1 K -1 of cast-Ce 0.75 Fe 3 CoSb 12 to 1.02 W m -1 K -1 of TGZM-Ce 0.75 Fe 3 CoSb 12 at 693 K. As a consequence, TGZM-Ce 0.75 Fe 3 CoSb 12 approaches a high power factor of 11.7 μW cm -1 K -2 and low thermal conductivity of 1.72 W m -1 K -1 at 693 K, leading to a peak zT of 0.48 at 693 K, which is 10 times higher than that of cast-Ce 0.75 Fe 3 CoSb 12 . This study indicates that our facile TGZM method can effectively synthesize high-performance CoSb 3 -based skutterudites by impurity removal and set up a solid foundation for further development.

The first linear silver supercluster based on icosahedral Ag 13 units has been constructed via bridging of dpa ligands: Ag 61 (dpa) 27 (SbF 6 ) 4 (Hdpa = dipyridylamine) ( Ag 61 ). Single-crystal X-ray diffraction reveals that this rod-shaped cluster consists of four vertex-sharing Ag 13 icosahedra in a linear arrangement. This Ag 61 cluster represents the longest one-dimensional metal nanocluster with a resolved structure. Unprecedented electron coupling develops between their constituent Ag 13 units. Theoretical studies disclose that the stabilities of the two superclusters are dictated by a strong interaction between the Ag 13 units as well as the ligand effect of the dpa-Ag motifs. The quantum size effect accounts for the significant enhancement of the metal-related absorptions and the red shift at the near-infrared region as the length of the cluster increases. This work sheds light on the evolution of one-dimensional materials and an understanding of the electronic communication between the constituent clusters.

A visible-light photoredox catalyzed radical cascade cyclization of simple ethers with cyanamides is developed at room temperature. This strategy involves sequential inert C sp3 -H/C sp2 -H functionalizations through intermolecular addition reaction of oxyalkyl radicals to N -cyano groups followed by radical cyclization of iminyl radicals in situ generated with C-2 aryl rings. This method allows for efficient synthesis of tetracyclic benzo[4,5]imidazo[1,2- c ]quinazolines. Importantly, this is the first example of an intermolecular-intramolecular radical cascade cyclization reaction of cyanamides.

Owing to the intrinsically good near-room-temperature thermoelectric performance, β-Ag 2 Se has been considered as a promising alternative to n-type Bi 2 Te 3 thermoelectric materials. Herein, we develop an energy- and time-efficient wet mechanical alloying and spark plasma sintering method to prepare porous β-Ag 2 Se with hierarchical structures including high-density pores, a metastable phase, nanosized grains, semi-coherent grain boundaries, high-density dislocations, and localized strains, leading to an ultralow lattice thermal conductivity of ∼0.35 W m -1 K -1 at 300 K. A relatively high carrier mobility is obtained by adjusting the sintering temperature to obtain pores with an average size of ∼260 nm, therefore resulting in a figure of merit, zT, of ∼0.7 at 300 K and ∼0.9 at 390 K. The single parabolic band model predicts that zT of such porous β-Ag 2 Se can reach ∼1.1 at 300 K if the carrier concentration can be tuned to ∼1 × 10 18 cm -3 , suggesting that β-Ag 2 Se can be a competitive candidate for room-temperature thermoelectric applications.

In this work, we prepared flexible carbon-fiber/semimetal Bi nanosheet arrays from solvothermal-synthesized carbon-fiber/Bi 2 O 2 CO 3 nanosheet arrays via a reductive calcination process. The flexible carbon-fiber/semimetal Bi nanosheet arrays can function as photocatalysts and photoelectrocatalysts for 2,4-dinitorphenol oxidation. Compared with carbon-fiber/Bi 2 O 2 CO 3 nanosheet arrays, the newly designed flexible carbon-fiber/semimetal Bi nanosheet arrays show enhanced ultraviolet-visible (UV-vis) light absorption efficiency and photocurrent, photocatalytic, and photoelectrocatalytic activities. Photocatalytic analyses indicate that the surface plasmon resonance (SPR) of semimetal Bi occurs under solar-simulated light irradiation during the photocatalytic process. The carbon-fiber traps the hot electrons exerted from the SPR of semimetal Bi and creates holes in the semimetal Bi nanosheets, which boosts the photocatalytic activity of the carbon fiber through plasmonic sensitization. Both photocatalytic experiments and density functional theory (DFT) calculations indicate that the electrons transferred to the carbon fiber and the holes created in semimetal Bi contribute to the formation of •O 2 - and •OH, respectively. The synergistic effect between electrocatalysis and photocatalysis under the solar-simulated light results in almost complete degradation of 2,4-dinitorphenol during the photoelectrocatalytic process. This work realizes a non-noble-metal plasmonic catalyst and provides a new avenue for the commercialization of photocatalysis and photoelectrocatalysis using the separable and recyclable carbon-fiber/semimetal Bi nanosheet arrays in the environment-related field.

Porous structure possesses full potentials to develop high-performance thermoelectric materials with low lattice thermal conductivity. In this study, the n -type porous nanostructured Bi 2 Te 3 pellet is fabricated by sintering Bi 2 Te 3 nanoplates synthesized with a facile solvothermal method. With adequate sublimations of Bi 2 TeO 5 during the spark plasma sintering, homogeneously distributed pores and dense grain boundaries are successfully introduced into the Bi 2 Te 3 matrix, causing strong phonon scatterings, from which an ultralow lattice thermal conductivity of <0.1 W m -1 K -1 is achieved in the porous nanostructured Bi 2 Te 3 pellet. With the well-maintained decent electrical performance, a power factor of 10.57 μW cm -1 K -2 at 420 K, as well as the reduced lattice thermal conductivity, secured a promising zT value of 0.97 at 420 K, which is among the highest values reported for pure n -type Bi 2 Te 3 . This study provides the insight of realizing ultralow lattice thermal conductivity by synergistic phonon scatterings of pores and nanostructure in the n -type Bi 2 Te 3 -based thermoelectric materials.

Copper sulfide has been regarded as a promising thermoelectric material with relatively high thermoelectric performance and abundant resource. Large-scale synthesis and low-cost production of high-performance thermoelectric materials are keys to widespread application of thermoelectric technology. Here, Cu 2- x S particles encapsulated in a thin carbon shell are fabricated by a scalable wet chemical method (19.7 g/batch). The synthesized particles go through the crystal-phase transition from orthorhombic to tetragonal during high-temperature annealing and sintering. After the phase transition, electrical conductivity of this composite (Cu 2- x S@C) increases by approximately 50% compared to that of the pure Cu 2- x S sample, and can be attibuted to an increase in carrier concentration. Phonon scattering interface formation and superionic phase of Cu 2- x S@C results in very low lattice thermal conductivity of 0.22 W m -1 K -1 , and maximum thermoelectric figure of merit ( ZT) of 1.04 at 773 K, which is excellent for thermoelectric performance in pure-phase copper sulfide produced via chemical synthesis. This discovery sets the stage for the use of facile wet chemical synthesis methods for large-scale transition-metal chalcogenide thermoelectric material production.

We report the synthesis and crystal structure determination of two novel chiral gold nanoclusters. By utilizing BINAP, we isolate atomically precise intrinsically chiral Au nanoclusters [Au 9 ( R-/ S-BINAP) 4 ](CF 3 COO) 3 and [Au 10 ( R-/ S-BINAP) 4 ( p-CF 3 C 6 H 4 C≡C)](CF 3 COO) 3 in high yield with one-pot synthesis. Au 9 has C 2 geometry, while Au 10 is C 1 symmetric. Interestingly, reversible interconversion between Au 9 and Au 10 can be realized by the addition or removal of a RC≡CAu component. The transformation from Au 9 to Au 10 leads to significant enhancement of CD signals. The maximum anisotropy factor in the visible region of [Au 10 (BINAP) 4 ( p-CF 3 C 6 H 4 C≡C)] 3+ is the hitherto largest (up to 6.6 × 10 -3 ) among gold nanoclusters, which is approximately twice of that of [Au 9 (BINAP) 4 ] 3+ . This work demonstrates that the chiroptical activity of gold nanoclusters can be modulated by structural control through the introduction of second ligands.

In this study, we fabricate In/Cd codoped octahedron-shape Sn(CdIn) x Te 1+2 x microcrystals with a promising thermoelectric performance by using a facile solvothermal method. The high hole-carrier concentration of pristine SnTe is significantly reduced through effective In/Cd codoping, which increases the Seebeck coefficient in a wide temperature range. Moreover, codoped In/Cd not only modifies the band structure by creating the resonance energy level at the valence band and converging light hole and heavy hole valence bands of SnTe but also provides In/Cd-rich nanoprecipitates in the matrix, leading to a high power factor of ∼26.76 μW cm -1 K -2 at 773 K in the sintered SnIn 0.03 Cd 0.03 Te 1.06 . Compared with the bulk counterparts, a much lower lattice thermal conductivity is achieved over a wide temperature range because of strong phonon scattering by point defects, nanoprecipitates, lattice distortion, and grain boundaries in the sintered SnIn x Cd x Te 1+2 x ( x = 3 and 4%) samples. Consequently, a high ZT of ∼1.12 is obtained at 773 K in the p-type SnIn 0.03 Cd 0.03 Te 1.06 , suggesting that nanoprecipitate-included Cd/In codoped octahedron-shaped Sn(CdIn) x Te 1+2 x microcrystals are a convincing candidate for medium-temperature thermoelectric applications.

A novel visible-light-induced aza-pinacol rearrangement was developed for the first time. In this approach, the addition of the N-centered radical to the C═C bond of alkylidenecyclopropanes delivers a variety of cyclobutanimines and γ-butyrolactones, with all-carbon quaternary centers via the ring expansion of the cyclopropyl group, in moderate to good yields under mild reaction conditions.

The 2,5-disubstituted thienosultines (5,7-disubstituted 1,4-dihydro-1H-3lambda(4)-thieno[3,4-d][2,3]oxathiin-3-oxides) 5a-d were prepared from the corresponding dichlorides 4a-d with the commercially available Rongalite (sodium formaldehyde sulfoxylate) in 17-60% yields. When heated in the presence of electron-poor dienophiles, sultines 5a-d underwent elimination of SO(2), and the resulting non-Kekulé biradicals 7a-d were intercepted as the 1:1 adducts 8-12 in good to excellent yields. The pyrolysis of sultines and sulfolenes with different concentrations of dienophiles revealed that either a preequilibrium between starting reagents and biradical species or Diels-Alder and retro-Diels-Alder reaction mechanisms may be involved; however, more work is necessary to establish the proposed mechanisms. Reaction of sultine 5b with nBuLi was found to undergo a nucleophilic ring-opening reaction to give sulfinyl alcohol 17 after H(2)O workup. When sultine 5a was heated in benzene in a sealed tube in the presence of methanol, methanol-d(4), or 2-mercaptoethanol, the respective 1:1 trapping adducts 19-21 as well as the rearranged sulfolene 6a were isolated in similar amounts. The isolation of adducts 19-21 may be explained by the involvement of either biradical or ionic intermediates during the pyrolysis.