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Carbon nitride (C3N4) is a promising metal-free photocatalyst for solar-to-energy conversion, but bulk carbon nitride (BCN) shows insufficient light absorption, sluggish photocarrier transfer and moderate activity for photocatalysis. Herein, a facile strategy to significantly increase solar spectrum absorption of the functionalized porous carbon nitride nanosheets (MFPCN) via molecule self-assembly engineering coupled thermal polymerization is reported. This strategy can greatly enhance the wide-solar-spectrum absorption of MFPCN up to 1000 nm than most reported carbon nitride-based photocatalysts. Experimental characterizations and theoretical calculations together display that this strategy could introduce hydroxyl groups into the structure of MFPCN as well as the rich pores and active sites at the edges of framework, which can narrow the bandgap and accelerate the transfer and separation of photoinduced carries. As a result, the optimal MFPCN photocatalyst exhibit the excellent photocatalytic hydrogen evolution rate of 7.745 mmol g-1h−1 under simulated solar irradiation, which is ≈13 times that of BCN with remarkable durable CO2 reduction activities. New findings in this work will provide an approach to extend solar spectrum absorption of metal-free catalysts for solar fuel cascades.

It is especially significant to design and construct high-performance and stable three-dimensional (3D) bifunctional nanoarchitecture electrocatalysts toward overall water splitting. Herein, we have constructed 3D self-supported phosphorus-doped ruthenium-cobalt nanowires on nickel foams (RuCoP/NF) via a simple hydrothermal reaction followed by a low-temperature phosphating reaction. Doping P can not merely enhance the intrinsic activity of electrocatalysts for overall water splitting but at the same time increase electrochemical surface areas (ECSAs) to expose more accessible active sites. As a 3D bifunctional catalyst, RuCoP/NF demonstrates superior performance for HER (44 mV@10 mA cm-2) and OER (379 mV@50 mA cm-2) in 1.0 M KOH electrolyte solution. The overall water-splitting system was assembled using RuCoP/NF as both anode and cathode. Besides, it exhibits a voltage of 1.533 V at a current density of 10 mA cm-2 and long-term durability within 24 h. P-dopant changes the electron structure of Ru and Co, which is conducive to the formation of Ruδ- and Coδ+, resulting in the adjustment of binding H*/OH* and the improvement of the overall water-splitting reaction kinetics. This work provides a facile method to produce heteroatom-doped and high-performance catalysts for efficient overall water splitting.

Solution-processable organic–inorganic hybrid perovskites are being widely investigated for many applications, including solar cells, light-emitting diodes, photodetectors, and lasers. Herein, we report, for the first time, successful fabrication of xerographic photoreceptors using methylammonium lead iodide (CH3NH3PbI3) perovskite as a light-absorbing material. With the incorporation of polyethylene glycol (PEG) into the perovskite film, the ion migration inherent to the perovskite material can be effectively suppressed, and the resulting photoreceptor exhibits a high and panchromatic photosensitivity, large surface potential, low dark decay, and high environmental resistance and electrical cycling stability. Specifically, the energies required to photodischarge one half of the initial surface potential (E0.5) are 0.074 μJ cm−2 at 550 nm and 0.14 μJ cm−2 at 780 nm, respectively. The photosensitivites outmatch those of the conventionally used organic pigments having narrow spectral responses. Our findings inform a new generation of highly efficient and low-cost xerographic photoreceptors based on perovskite materials.

The trap states at the surface and grain boundaries of perovskite films have a great influence on the photovoltaic performance and stability of perovskite solar cells (PSCs). Herein, lead sulfide (PbS) was introduced on the surface of perovskite films through in situ reaction with thioacetamide (TAA) in solution. With the PbS layer, the trap state density of the perovskite film was significantly reduced, and charge extraction efficiency was enhanced from perovskite to the external charge transport layer. In addition, it was found that the water-insoluble PbS layer could effectively protect the perovskite film from the moisture permeation. As a result, the perovskite solar cell exhibited a stable output efficiency of 22.04% with high stability.

Organic–inorganic hybrid perovskite materials have attracted significant attention due to their intriguing optical and electrical properties. However, it is a challenge to grow a perovskite thin film with controlled crystallinity and large-sized grains by a simple solution process, which is important for highly efficient and stable perovskite solar cells. Herein, a methylamine-assisted secondary grain growth approach is developed for post-annealing of a methyl ammonium lead iodide (MAPbI3) perovskite film in a controlled methylamine (MA0) atmosphere, leading to the formation of a full-coverage and highly oriented perovskite film with large grain sizes up to tens of microns. The resultant perovskite film shows low trap density, strong photoluminescence, and a prolonged decay lifetime. The perovskite photovoltaic device shows an enhanced power conversion efficiency (PCE) of 20.81% with good environmental stability. The method reported here provides a promising and facile route to fabricate high-quality MAPbI3 perovskite films for efficient optoelectronic devices.

The one-step hydroalkylation of benzene to cyclohexylbenzene (CHB) needs to occur on bifunctional metal/zeolite catalysts, and introducing more acid sites to match the metal sites plays a key role in improving the matching of acid/metal sites toward the requirements of benzene hydroalkylation. Herein, we designed and constructed a Si–Al framework coating with extra acid sites outside the surface of the Pd/HBeta catalyst and obtained a zeolite-encaged Pd NP structure (Pd@HBeta). Notably, the Pd@HBeta catalysts achieved excellent catalytic performance with 44.0% CHB selectivity at about 85.0% benzene conversion, which is much higher than that of the Pd/HBeta catalyst with a CHB selectivity of 25.1% at the same benzene conversion. The remarkable increment of CHB selectivity of Pd@HBeta is mainly attributed to the extra acid sites provided by the coated Si–Al framework as well as the increase of the B/L ratio. Moreover, the adsorption capacity of benzene and cyclohexene is greatly improved after introducing extra acid sites by coating the Si–Al framework, which is beneficial for both hydrogenation and alkylation. Further DFT calculations reveal that C6H10 can easily desorb from Pd NPs and migrate to the acidic channel of HBeta in the Pd@HBeta catalyst than that in Pd/HBeta. Our work presents an elegant example of catalytic hydroalkylation selectivity regulation by coating an extra Si–Al framework to enhance the matching of acid/metal balance.

Two-dimensional (2D) layered heterojunctions with a staggered band structure and unique interface properties exhibit promising application prospects in photocatalytic pollutant removal, water splitting, and CO2 reduction. Ultrathin 2D/2D heterojunctions with a large specific surface area and a short migration path of the photogenerated charge always illustrate a better photocatalytic performance than non-ultrathin 2D heterojunction photocatalysts. In this study, a novel ultrathin 2D/2D heterojunction of the Bi2O2(OH)(NO3)/BiOBr nanosheet composite (ultrathin BION/BiOBr) was in situ self-assembled though a cetyltrimethylammonium bromide assisted one-step hydrothermal method. Benefiting from the advantage of the unique ultrathin heterojunction structure, the ultrathin 2D/2D BION/BiOBr heterojunctions exhibit a greatly improved photocatalytic removal effect for multiple pollutants compared to the nanocrystal BION/BiOBr, pure BION. As a representative, the ultrathin 2D/2D Br-modified BION/BiOBr heterojunction shows an enhanced tetracycline degradation rate of 76%, which corresponded to a higher photodegradation rate constant of 0.01116 min–1 when compared to pure BION (17%, 0.00161 min–1) and nanocrystal BION/BiOBr (24%, 0.00223 min–1) under visible-light irradiation for 2 h. A series of characterization and density functional theory calculations demonstrate the enhanced separation and migration efficiency of the photogenerated electrons and holes over the ultrathin heterojunction, facilitating the formation of oxidizing groups for the organic pollutant removal. The possible mechanism of the TC photodegradation and the possible photodegradation pathway are also investigated in detail. This work provides a feasible method for constructing ultrathin 2D/2D heterojunction materials for environmental purification.

Developing high-efficiency and low-cost catalysts for the hydrogen evolution reaction (HER) and hydrogen generation from chemical hydrogen storage materials are both significant and critical for th...

Long intergenic non-coding RNAs (lincRNAs) are long non‑coding transcripts from the intergenic regions of annotated protein‑coding genes. lincRNA cyclooxygenase 2 (Cox2) is an early‑primary response gene regulated by the NF‑κB signaling pathway in macrophages. It was found that lincRNACox2 was significantly increased in patients with the Mycobacterium tuberculosis (M. tuberculosis) H37Ra strain infection and macrophages, using reverse transcription-quantitative PCR (RT‑qPCR). ELISA, western blotting and RT‑qPCR results indicated that the inflammatory response factors tumor necrosis factor‑α, interferon‑γ, interleukin‑6, Cox2 and inducible nitric oxide synthase were significantly increased in H37Ra infected macrophages. In addition, the inflammatory regulating proteins NF‑κB and Stat3 were significantly increased in H37Ra infected macrophages but decreased in lincRNACox2 knockdown macrophages infected with H37Ra. Moreover, the knockdown of lincRNACox2 increased the apoptotic rate of H37Ra infected macrophages and facilitated the proliferation of H37Ra. Collectively, the present results suggested that lincRNACox2 may be required for the activation of NF‑κB and Stat3, in order to regulate inflammatory responses involved in resistance to M. tuberculosis infection.

Solution-processed polycrystalline perovskite films have detrimental defects in the bulk and surfaces/grain boundaries, especially the uncoordinated lead ions (Pb2+) with low formation energy, limiting both the performance and stability of the photovoltaic devices. In this work, a conductive polymer poly(3,4-ethylenedioxythiophene) (PEDOT) is incorporated into a bulk perovskite film by a facile in-situ polymerization method, where 5-bromo-2,3-dihydro-thieno[3,4-b] [1] , [4] dioxine (BEDOT) as monomer is directly added to a perovskite precursor solution and then in-situ polymerized within the perovskite film during the film formation. The PEDOT is chemically anchored at the surface and grain boundaries of the perovskite film via interaction of sulfur and oxygen atoms in PEDOT with uncoordinated lead ions in the perovskite, passivating the surface and bulk defects and also improving the charge extraction efficiency in the solar cell. Moreover, robust and hydrophobic properties of PEDOT can enhance the thermal and moisture resistance of the perovskite film. As a result, a champion power conversion efficiency (PCE) of 22.58% is achieved, along with significantly enhanced environmental, thermal, and light-soaking stability.

Developing a low-cost and efficient photocatalysts activated peroxymonosulfate (PMS) for organic pollutants degradation are recognized as an importance way for dealing with environmental pollution. In this work, Fe-rectorite catalyst was synthesized by a simple impregnation-calcine method to synergetic photo activate PMS for antibiotics degradation. As expected, the Fe-rectorite/PMS/Light system exhibits superior catalytic performance for tetracycline (TC) removal, which achieving 96.4% removal rate of TC (30 mg/L) under light within 60 min. Fe-retorite has better degradation performance for TC than rectorite under photo-mediation. The enhancement of the degradation performance of TC by Fe-retorite can be attributed to the improvement of the separation efficiency of photogenerated electrons and holes in the rectorite by the loading of Fe

Studies have received intense concern on the classical conductive polymers for thermoelectric (TE) materials; but polypyrrole (PPy) seemed to be an exception due likely to its relatively poor TE behaviors. In this work, we present an unconventional two-step electrochemical post-treatment strategy to improve the TE performance of the PPy films electrodeposited, namely first oxidation at + 0.7 V and subsequent reduction at different potentials ranged from − 1.3 to 0 V (vs Ag/Ag+). The doping level of PPy films was regulated accurately by controlling the applied potential. Consequently, the significantly enhanced power factor and figure of merit have been achieved, which are far higher than those of the films obtained via one-step electrochemical post-treatment and hit the records high for the pure PPy. This indicates that the two-step electrochemical post-treatment is a feasible and effective protocol for perfecting thermoelectric performance of polymers, and may be extended to other conducting polymeric systems.

Resourcing solid waste as catalysts for activating peroxymonosulfate (PMS) used in high-salt organic wastewater treatment, to realize waste control, is meaningful, promising, and a win–win strategy for environmental remediation. Here, a magnetically recyclable hybrid originating from used warm paste (greater than92% yield) was developed using water washing to activate PMS for antibiotics degradation under hypersaline system. Scanning electron microscope (SEM) and transmission electron microscopy (TEM) measurements indicated that the hybrid is a sheet structure with active Fe sites uniformly dispersed on the surface. The hybrid displayed an excellent PMS activation capacity; it is superior to those of classical Fe3O4 and Co3O4, which could degrade the tetracycline (TC). However, under a high-salt (0.2 mol/L Na2SO4) or mixed salts condition, the hybrid exhibited TC degradation performance. Moreover, a detailed investigation of the impact on of TC removal indicated that the preferable conditions were pH = 6, temperature = 25 °C, catalyst = 0.3 g/L and PMS = 0.3 g/L. Systematic experiments uncovered the hybrid exhibiting superb catalysis universality and adaptability in three refractory organics, 5 natural polluted water matrices, and coexisting-ions system, as well as five times, recycle processes. The surface chemical analysis combined with quenching experiment and electron paramagnetic resonance (EPR) test confirmed the PMS activation mechanism and the reactive radicals contributed in order of 1O2 > •OH > SO4•−. Considering its performance, stability and applicability, the warm paste hybrid would be good for PMS activation toward high-salt environment remediation. Thus inducing a novel direction for solid waste treatment and mitigated resource scarcity.

Bimetallic catalyst with three-dimensional hierarchical structure is very promising for Fenton-like reaction owing to its synergistic effect and unique microstructure. The combination of photocatalysis with peroxymonosulfate (PMS) as a good electron acceptor is an effective method to avoid the combination of electrons and holes, further significantly improving the degradation efficiency of refractory organics. In this work, a three-dimensional hierarchical and spinel-type MnCo2O4 catalyst was studied as a proof of concept for effective photoinduced PMS activation towards antibiotics degradation. As expected, the three-dimensional hierarchical MnCo2O4 (3D MnCo2O4) catalyst showed an excellent catalytic activity for PMS activation towards tetracycline (TC) degradation under the light irradiation over MnO2/light/PMS systems, Co3O4/light/PMS systems and general MnCo2O4/light/PMS systems. In a wide pH range (3-9) and a complex anionic (Cl−, HCO3−, NO3− and PO43−) environment, the 3D MnCo2O4/PMS/light system also can still degrade 95% of TC within 15 min and keep good catalytic stability. The superiority of 3D MnCo2O4/PMS/light system towards efficiency of TC degradation is attributed to its synergistic effect of Co-Mn on Co (III)/Co (II) cycle, peculiar microstructure and photocatalysis combination. Our work provides a promising highly-efficient heterogeneous catalytic system for environmental application.

Developing a low-cost and excellent catalyst for advanced oxidation process (AOPs) to degrade refractory organic contaminants is still an urgent problem. In this work, a copper oxide decorated natural rectorite (Cu-R) catalyst was successfully synthesized by a facile impregnation method. Intriguingly, Cu-R possessed excellent performance in removing tetracycline (TC) through photoinduced peroxymonosulfate (PMS) activation, and its reaction rate constants were ca. 4.3 times and 7.0 times that of Fe2O3 and Co3O4, respectively. Moreover, the effects of reaction parameters on the photoinduced Cu-R activation of PMS to degrade TC were investigated in detail. The results showed that the system exhibited excellent impact resistance to Cl−, HCO3− and NO3− in aqueous solution. Cu-R could not only exhibit excellent removal of TC in a wide pH range of 5–9, but also maintain the stability of the catalyst. The electron paramagnetic resonance test and quenching experiments proved that the excellent TC removal ability could be mainly attributed to the synergistic effect between CuO and rectorite under the assistant of light, which was beneficial for the activation of PMS and then produced a large number of active radicals such as •OH and O2•-. Importantly, a possible path for TC degradation was given by the LC-MS analysis. The prepared Cu-R can provide a low-cost, high-efficiency and promising catalyst for the treatment of antibiotic wastewater by PMS activation with photoassistent.

Full light photo-Fenton and photo-thermal effect are of great importance but deserve attentions far insufficient in advanced oxidation progresses for extensive environmental remediation. Herein, ultraviolet-visible-near infrared (UV–vis-NIR) light absorbance and photo-thermal conversion were induced into H2O2 activation towards refractory antibiotics elimination from wastewater through green recyclable rGO-ZnFe2O4 developed via ultrasonic method. Interestingly, photo-thermal synergy presents much superior performance than that of solely photo-Fenton or thermal-Fenton process. Multiple light reflection inner ZnFe2O4 microsphere strengthens UV–vis capture and thermal conversion in degradation reaction. Orbital hybridization and electron rearrangement endow rGO-ZnFe2O4 wide NIR absorbency, fast thermal transfer and photo-generated electrons-holes separation for photo-thermal Fenton progress. Degradation rate of ciprofloxacin on rGO-ZnFe2O4 is found 3 times of ZnFe2O4 under full light exposure which can heat solution from room temperature to 70 °C, while 4 times under NIR irradiation where solution is heated to 46 °C. The great differences are mainly originated from photo-induced thermal energy, which in-situ heating active sites to lower H2O2 activation barrier, accelerate Fe2+/Fe3+ cycle and facilitate spread of radicals. Radicals contribute in OH > h+ > O2 − under full light irradiation, while perform in h+ > O2 − > OH when taking away photo-generated heat. Results based on systematic experiments and theory calculation imply the strong potential of photo-thermal Fenton in pollutants control, which proposes novel strategy in Fenton reaction for environmental remediation with effective utilization of solar energy.

Polymer/inorganic nanocomposite (NC) hydrogels usually display super mechanical properties, due to their 3D crosslinked network of delaminated inorganic nanoparticles and polymers as well as strong interfacial interactions. Multiple functions including photoluminescence are strongly desired for their applications. In this study, we report layered rare-earth hydroxide (LRH)/polyacrylamide NC hydrogels with highly colour-tunable photoluminescence functions by a cascaded energy transfer effect. These NC hydrogels based on LRHs containing Gd3+, Tb3+ or Eu3+ ions are fabricated via a convenient and green in situ polymerization procedure. Diverse photoluminescent colours are clearly observed, ranging from green, yellow-green, yellow, reddish-orange, yellowish pink, pink to bluish violet. Furthermore, these NC hydrogels exhibit long luminescence lifetimes and high quantum efficiencies. More interestingly, such fascinating photoluminescence features are highly tunable by varying the constituent or concentration of LRHs, and the excitation wavelength. Finally, a cascaded energy transfer pathway is proposed to elucidate the molecular mechanism of the tunable multiple-colour photoluminescence functions, i.e. the LRH host → sensitizer sodium salicylate (SA) → Tb3+, and finally Tb3+ → Eu3+.

The low toxicity, narrow bandgaps, and high charge‐carrier mobilities make tin perovskites the most promising light absorbers for low‐cost perovskite solar cells (PSCs). However, the development of the Sn‐based PSCs is seriously hampered by the critical issues of poor stability and low power conversion efficiency (PCE) due to the facile oxidation of Sn2+ to Sn4+ and poor film formability of the perovskite films. Herein, a synthetic strategy is developed for the fabrication of methylammonium tin iodide (MASnI3) film via ion exchange/insertion reactions between solid‐state SnF2 and gaseous methylammonium iodide. In this way, the nucleation and crystallization of MASnI3 can be well controlled, and a highly uniform pinhole‐free MASnI3 perovskite film is obtained. More importantly, the detrimental oxidation can be effectively suppressed in the resulting MASnI3 film due to the presence of a large amount of remaining SnF2. This high‐quality perovskite film enables the realization of a PCE of 7.78%, which is among the highest values reported for the MASnI3‐based solar cells. Moreover, the MASnI3 solar cells exhibit high reproducibility and good stability. This method provides new opportunities for the fabrication of low‐cost and lead‐free tin‐based halide perovskite solar cells., Tin fluoride and methylammonium iodide are employed as precursors for the fabrication of methylammonium tin iodide (MASnI3) film via an ion exchange/insertion reactions approach, and a highly uniform, pinhole‐free perovskite film is obtained with a high concentration of SnF2 and a low content of Sn4+. The corresponding solar cell exhibits the highest power conversion efficiency of 7.78% with high reproducibility and stability.

As an important regulator of neddylation, neural precursor cell expressed developmentally downregulated 8 (Nedd8)‑conjugating enzyme E2M (UBE2M) mediates cullin neddylation. Upregulation of the neddylation pathway is associated with tumor progression in intrahepatic cholangiocarcinoma (ICC). The present study was designed to assess the effects of Nedd8‑conjugating enzyme UBE2M knockdown on intrahepatic cholangiocarcinoma cells, and to determine the potential underlying mechanisms. UBE2M and associated protein expression levels were determined via immunohistochemistry and western blotting. ICC cells were transfected with short hairpin RNA to knockdown UBE2M expression. Cell Counting Kit‑8 and colony formation assays, and xenograft experiments were used to examine cell viability and colony survival in vitro, and tumor formation in vivo. Survival was evaluated using Kaplan‑Meier analysis and log‑rank tests. Patients with ICC presenting high expression of UBE2M exhibited worse accumulative recurrence and overall survival compared with patients with low expression. Knockdown of UBE2M expression led to a decrease in the viability and clonogenic survival of QBC939 and HUCCT1 cells, and suppressed tumor formation in vivo. UBE2M silencing caused accumulation of cullin‑RING ligase substrates (chromatin‑licensing and DNA replication factor 1 and origin recognition complex subunit 1), inducing DNA damage responses and apoptosis. The present findings suggested that UBE2M serves an important role in ICC progression and may present as a novel target for the treatment of ICC.

Nowadays, using solar energy to convert CO2 into hydrocarbon fuels such as CO and methanol is considered as an attractive approach to alleviate environmental pollution and the energy crisis. However, the easy recombination of photo-generated carriers and holes of photocatalyst is still the main factor that inhibits photocatalytic performance for CO2 conversion. In this study, the BiO[Formula: see text]/Bi2O[Formula: see text] heterojunction complex was successfully synthesized via a facile hydrothermal method. The BiO[Formula: see text]/Bi2O[Formula: see text] heterogeneous catalyst shows greatly improved photocatalytic performance for CO2 reduction, and the CO and CH4 yields obtained on BiO[Formula: see text]/Bi2O[Formula: see text] are 6.8 and 16 times compared with pure BiO[Formula: see text]. The improved photocatalytic performance can be ascribed to the rapid charge separation on BiO[Formula: see text]/Bi2O[Formula: see text] interface, thereby providing a favorable surface with suitable electronic structure for CO2 reduction. Subsequently, a possible photocatalytic mechanism was proposed to explain the improved performance of photocatalytic CO2 reduction.

A direct evidence by infrared dichroism is reported for the first time for the effect of molecular orientation on thermoelectric (TE) performance of organic polymer materials. The preferred orientation was induced by mechanical uni-axial stretching of the films of neat polyaniline (PANI) and its nanocomposites with reduced graphene oxide (rGO) or multi-walled carbon nanotube (MWCNT). Five characteristic bands of Fourier transform infrared (FTIR) spectra were chosen, and quantitative investigations were carried out using the dichroic ratios measured by polarized FTIR spectra. The influences of draw ratio and content of inorganic carbon nanoparticles were taken into account. The results show that the TE performance (including anisotropic TE function) can be conveniently tuned by polymer molecular orientation induced by mechanical stretching, which shed light on the understanding of molecular mechanism towards structure-TE performance relationship, and will speed up the applications of organic polymer TE materials.

Being green energy materials, thermoelectric (TE) materials can realize direct energy conversions between heat and electricity, thus have widely applications in both TE generators for energy harvesting and local cooling. Especially, low-quality waste heat can be conveniently used. In the recent several years, there is rapidly growing interest in organic conducting polymer/carbon particle TE composites, which synergistically combine the advantages of both carbon particles and polymer materials. In this review, the recent progress is systematically summarized in the order of the dimensionality of the carbon particles (2D, 1D and 0D) and the type of polymer matrix. Synergistic effect and polymer ordered structure, morphological tuning, devices and flexible films are highlighted. Finally, prospects and suggestions for future studies are presented.

Organic thermoelectric materials are emerging green energy materials, where n-type candidates are of special interest due to the strong demand for thermoelectric modules with flexibility, light weight, large-area fabrication and ease of processing into versatile shapes. Here, an exciting novel strategy to prepare an n-type single-walled carbon nanotube (SWCNT) is proposed by diethylenetriamine (DETA) doping (electron donation) and subsequent CaH2 treatment of the pristine SWCNT (p-type). The Seebeck coefficient and the electrical conductivity for the obtained DETA-CaH2-SWCNT are −41.0 ± 1.5 μV K−1 and 165 ± 10 S cm−1, respectively. A possible mechanism is discussed for the p- to n-type conversion. Then, a multilayered alternating stacked structure is employed to construct thermoelectric modules which realize the conduction layers electrically in series and thermally in parallel. Importantly, the module containing 14 couples displays large open circuit voltages of 62 mV and 125 mV at temperature gradients (ΔT) of 55 K and 110 K, respectively, and a maximum output power of 649 nW at ΔT = 55 K. The strategy proposed here opens a new way to fabricate organic n-type materials and flexible thermoelectric modules. These promising results show great potential in fabrication and applications of flexible and wearable power-conversion devices for next-generation power generators and waste-heat-recovery systems.

Although organic polymer/inorganic particle composites with thermoelectric (TE) performance have witnessed rapid progress in recent years, previous studies mainly focused on a few classically conducting polymers. Schiff base polymers have various advantages such as their ease of preparation, versatile derivatives and adjustable complexation. Unfortunately, studies of Schiff base TE composites are very scarce. The only example reported so far is obtained via a two-step procedure, i.e. synthesis of monomer and subsequent polymerization. Here, we report a convenient one-pot preparation and the TE performances of a series of flexible composite films based on single-walled carbon nanotubes (SWCNTs) and a novel poly-Schiff base, which is achieved via a condensation reaction between glyoxal and p-phenylenediamine. Furthermore, the TE performance of the poly-Schiff base composites reported herein can be conveniently adjusted by chelating transition metal ions. The results reveal that both the preparation method and the poly-Schiff base/SWCNT mass ratio have important impacts on the composite TE performance. The electrical conductivities and the Seebeck coefficients for the physically mixed composites exhibit opposite variation tendencies with poly-Schiff base/SWCNT mass ratio, while the power factors increase with increasing mass ratio. At a poly-Schiff base/SWCNT mass ratio of 1 : 3, the physically mixed composite reaches the highest power factor of 77.7 ± 5.8 μW m−1 K−2. Finally, by chelating transition metal ions with 1,4-diazabuta-1,3-diene unit of poly-Schiff base, the TE performances of poly-Schiff base/transition metal/SWCNT composites are conveniently adjusted.

Recently, due to their unique advantages over inorganic materials, organic polymer thermoelectric (TE) materials have received considerable attention. However, most studies focus on TE performance enhancement. So far, little attention has been paid to large-area preparation, stretchability, super flexibility and mechanical stability, although these are the intrinsic advantages of polymer materials. Here we report for the first time large-area, stretchable, super flexible and mechanically stable TE films of polymer/carbon nanotube composites. Mechanically stretchable films with a diameter of ∼18 cm are achieved by common vacuum filtration, whose thicknesses and sizes can be conveniently adjusted. Despite direct observations of films under various deformations of bending, rolling or twisting, quantitative measurements of minimum bending radii (

The design of electrocatalysts with excellent performance and low cost is of great significance for the electrocatalytic water splitting. NiSe2 has been widely concerned because of its suitable adsorption energy and adjustable electronic structure for hydrogen evolution reaction (HER). Here, a hollow spherical NiSe2 catalyst was designed and prepared by the hydrothermal method. Thanks to the unique three-dimensional (3D) open configuration and favorable active components, it exhibits superior catalytic activity for HER. It delivers an overpotential of 330[Formula: see text]mV at the current density of 10[Formula: see text]mA[Formula: see text]cm[Formula: see text], corresponding to the Tafel slope of 128[Formula: see text]mV[Formula: see text]dec[Formula: see text]. This work demonstrates that the 3D hollow structure with large specific surface and rich internal space can effectively improve the mass transfer efficiency and electron transfer. This work may provide a controllable way for the design of hollow structure catalysts.

The development of high activity, long stability, and cost-efficient catalyst for overall water splitting is paramount for the scalable production of hydrogen. Herein, we report low ruthenium content ruthenium cobalt nanoalloys encapsulated in nitrogen-doped carbon layers synthesized via incipient-wetness impregnation-pyrolysis method (denoted as RuCo@NC-temp.). A series of characterizations reveal that trace amounts of ruthenium inserts into the cobalt lattice matrix that can form RuCo alloys. The optimized catalyst (RuCo@NC-750, 1.56 wt% Ru) shows superior catalytic performance for hydrogen evolution reaction in alkaline, acidic, and neutral media, as well as oxygen evolution reaction in alkaline media. The catalytic reaction displays an overpotential of 25 mV (1.0 M KOH), 29 mV (0.5 M H2SO4), and 163 mV (1.0 M PBS) for hydrogen evolution reaction and 308 mV (1.0 M KOH) for oxygen evolution reaction at a current density of 10 mA cm−2. RuCo@NC-750 needs only 1.54 V to achieve a current density of 10 mA cm−2 when it serves as both the anode and cathode material in a two-electrode electrolyzer. The excellent electrocatalytic performance can be attributed to the doping of ruthenium into the cobalt lattice matrix, which effectively enhance the electron transfer from the metal core to the carbon surface, and is beneficial for regulating the electronic structure of the carbon surface and strengthening the carbon-hydrogen bond and surface defects.

We report flexible films of organic–inorganic thermoelectric (TE) composites based on organometallic coordination compound [copper-phenylacetylide (PhC2Cu)] nanobelts and single-walled carbon nanotubes (SWCNTs). Interestingly, an unusual mechanochromic luminescence phenomenon from bright green to dark red is clearly observed after grinding the PhC2Cu crystalline nanobelts. The PhC2Cu/SWCNT composites display high mechanical flexibility and excellent TE performance. The maximum power factor at room temperature can reach as high as 200.2 ± 10.9 μW m–1 K–2. The present study opens an avenue to fabricate novel organic–inorganic TE composite materials using organometallic coordination compounds such as PhC2Cu.

We report reduced graphene oxide (rGO)/single-walled carbon nanotube (SWCNT) hybrid aerogels with enhanced thermoelectric (TE) performance and removal of organic solvents by designing 3D double-interconnected network porous microstructures. A convenient, cost-effective, and scalable preparation procedure is proposed compared with conventional high-temperature pyrolysis and supercritical drying techniques. The obtained hybrid aerogels are systematically characterized by apparent density, scanning electron microscopy, X-ray photoemission spectroscopy, Raman spectroscopy, and porosity. An enhanced TE performance of ZT ≈ ∼8.03 × 10–3 has been achieved due to the 3D double-interconnected network porous microstructure, the energy-filtering effect, and the phonon scattering at the abundant interfaces and joints. In addition, upon a large axial compression deformation, a high degree of retention of the Seebeck coefficient and a simultaneously significant enhancement of the electrical conductivity are observed. Fi...

Taking advantage of the high electrical conductivity of a single-walled carbon nanotube (SWCNT) and the large Seebeck coefficient of rylene diimide, a convenient strategy is proposed to achieve high-performance n-type thermoelectric (TE) composites containing a SWCNT and amino-substituted perylene diimide (PDINE) or naphthalene diimide (NDINE). The obtained n-type composites display greatly enhanced TE performance with maximum power factors of 112 ± 8 (PDINE/SWCNT) and 135 ± 14 (NDINE/SWCNT) μW m–1 K–2. A short doping time of 0.5 h can ensure high TE performance. The corresponding TE module consisting of five p–n junctions reaches a large output power of 3.3 μW under a 50 °C temperature gradient. In addition, the n-type composites exhibit high air stability and excellent thermal stability. This design strategy benefits the future fabricating of high-performance n-type TE materials and devices.

Although composites of organic polymers or n-type small molecule/carbon nanotube (CNT) have achieved significant advances in thermoelectric (TE) applications, p-type TE composites of small organic molecules as thick surface coating layers on the surfaces of inorganic nanoparticles still remain a great challenge. Taking advantage of in situ oxidation reaction of thieno[3,4-b]pyrazine (TP) into TP di-N-oxide (TPNO) on single-walled CNT (SWCNT) surface, a novel synthesis strategy is proposed to achieve flexible films of TE composites with narrow-bandgap (1.19 eV) small molecule coating on SWCNT surface. The TE performance can be effectively enhanced and conveniently tuned by poly(sodium-p-styrenesulfonate) content, TPNO/SWCNT mass ratio, and posttreatment by various polar solvents. The maximum of the composite power factor at room temperature is 29.4 ± 1.0 µW m-1 K-2 . The work presents a way to achieve flexible films of p-type small organic molecule/inorganic composites with clear surface coating morphology for TE application.

The cross-coupling reaction of diarylamines with aryl bromides/iodides can be effected by the Ni(II)–(σ-aryl) complex/PPh3/NaH system, and a preliminary investigation was conducted into the mechanism of this reaction.

The cross-coupling reaction of diarylamines with aryl bromides/iodides can be effected by the Ni(ii)-(sigma-aryl) complex/PPh(3)/NaH system, and a preliminary investigation was conducted into the mechanism of this reaction.