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Conductive coordination polymers (CPs) have potential in a wide range of applications because of their inherent structural and functional diversity. Three electrically conductive CPs (Cux C6 S6 , x=3, 4 or 5.5) derived from the same organic linker (benzenehexathiol) and metal node (copper(I)) were synthesized and studied. Cux C6 S6 materials are organic-inorganic hybrid copper sulfides comprising a π-π stacking structure and cooper sulfur networks. Charge-transport pathways within the network facilitate conductivity and offer control of the Fermi level through modulation of the oxidation level of the non-innocent redox-active ligand. Two Cux C6 S6 (x=4 or 5.5) CPs display high electrical conductivity and they feature a tunable structural topology and electronic structure. Cu4 C6 S6 and Cu5.5 C6 S6 act as degenerate semiconductors. Moreover, Cu5.5 C6 S6 is a p-type thermoelectric material with a ZT value of 0.12 at 390 K, which is a record-breaking performance for p-type CPs.

Osteoporosis leads to various complications, such as prosthesis loosening and periprosthetic fracture, after joint replacement. This is mainly due to the impaired osteogenesis and excessive osteoclastic activity in osteoporotic microenvironment, which leads to insufficient osseointegration between prostheses and host bone. In this study, a functional drug-releasing inorganic-organic bioactive interface was constructed, comprising inorganic three-dimensional (3D) printed porous titanium alloy interface and organic poloxamer 407 temperature-sensitive hydrogel loaded with a novel anti-osteoporosis drug (technetium methylenediphosphonate, 99Tc-MDP). The inorganic-organic bioactive interface showed good biocompatibility and exhibited a sustained release profile. This performance enhanced osteogenic differentiation, inhibited the expression of osteoclast-related genes and inhibited the osteoclastogenesis, as compared with traditional bisphosphonates (alendronate) in vitro. When implanted into the distal femoral defect using an osteoporotic rabbit model, the 99Tc-MDP-loaded bioactive interface exhibited the most stable osseointegration with native bone. Furthermore, the drug delivery system inhibited osteoclastic activity via regulation of the osteoprotegerin/receptor activator of NF-κB ligand (OPG/RANKL) signaling pathway, which significantly ameliorated the osteoporosis status to effectively prevent continuous bone destruction around the interface. This study has clinical significance, as it demonstrates that the 99Tc-MDP modified inorganic-organic interface serve as a novel artificial prosthetic interface for patients with poor osteogenesis.

Metal-bis(dithiolene) is one of the most promising structures showing redox activity, excellent electron transport and magnetic properties as well as catalytic activities. Perthiolated coronene (PTC), an emerging highly symmetric ligand containing the smallest graphene nanoplate was employed to manufacture a hybrid material with fused metal-bis(dithiolene) and graphene nanoplate, and it has been demonstrated as an efficient strategy for the construction of multifunctional materials recently. Herein, Co-PTC, a 2D MOF containing Co-bis(dithiolene) and coronene units is prepared via a homogeneous reaction for the first time as powder samples, which are bar-shaped microparticles composed of nanosheets. A neutral formula of [Co3 (C24 S12 )]n is verified for Co-PTC. Co-PTC plays an ultrahigh conductivity of approximately 45 S cm-1 at room temperature as compressed samples, which is among the highest value ever reported for the compressed powder samples of conducting MOFs. Moreover, Co-PTC exhibits good electrocatalytic performance in the hydrogen evolution reaction (HER) with a Tafel slope of 189 mV decade-1 and an operating overpotential of 227 mV at 10 mA cm-1 with pH=0, as well as a remarkable stability in the extremely acidic aqueous solutions, which is the best hydrogen evolution properties among metal-organic compounds.

Patients with osteoporosis are more likely to suffer prosthesis displacement, subsidence or periprosthesis fracture after prosthesis replacement. This is due to excessive osteoclast activity and a lack of bone marrow mesenchymal stem cell (BMSC) integration at the implant-bone interface locally in the setting of osteoporosis. In order to inhibit local excessive bone resorption and promote bone integration, we have constructed a porous titanium/poloxamer 407 hydrogel system loaded with zoledronate (ZOL), a bisphosphonate, to promote osteointegration in a rabbit model of osteoporosis. This composite scaffold (ZOL/gTi) showed good biocompatibility and sustained ZOL release along with the degradation of hydrogel. Not only does this system provide a three-dimensional structural network for BMSC proliferation but also locally released ZOL promotes proliferation and osteogenic differentiation while inhibiting osteoclast differentiation of BMSCs in vitro. After implantation of ZOL/gTi into a distal femoral defect in the rabbits, micro-CT, histological, push-out, as well as genetic and protein analyses revealed significant promotion of osteointegration with the aid of this composite scaffold. Here, we provide an important theoretical basis for the research and development of bioactive implant interfaces for patients with osteogenic defects, such as osteoporosis. Keywords: Bioactive interface, Zoledronate, Osteoporotic microenvironment, Osseointegration

Hybrid two-dimensional (2D) van der Waals (vdW) p–n junctions are attractive due to the controlled synthesis of the physical performances of organic semiconductors and quantum confinement effects of 2D materials, enabling highly tunable optoelectronic performances as well as low-cost processability. Here, hybrid 2D heterostructures are fabricated using a p-type semiconducting polymer (PDVT-10) and n-type MoS2. An ultra-thin film (∼9 nm) of the PDVT-10 polymer is formed using the Langmuir–Schaefer (LS) technique. Large-scale MoS2 monolayers are prepared using a chemical vapor deposition (CVD) method. The PDVT-10/MoS2 vertical heterojunction devices show ambipolar charge transport properties with a p-type maximum field-effect mobility of 0.3 cm2 V−1 s−1 and an n-type maximum field-effect mobility of 2.45 cm2 V−1 s−1. In addition, the heterojunctions exhibit a great photoresponse under white light as well as a clear rectifying behavior.

A graphene-like coordination polymer based on copper(II) benzenehexathiol (Cu-BHT, 1) with high electric conductivity (103 S·cm–1) was prepared recently. The high conductivity makes this material a good candidate for electrocatalysis, and here its catalytic activity toward hydrogen evolution reaction (HER) was evaluated. Cu-BHT shows good activity and stability for HER in acidic solutions under high current densities. By changing the preparation conditions, the morphology of Cu-BHT materials was controlled at the mesoscale, which allows the preparation of a thin film (TF-1), nanocrystal (NC-1), and amorphous nanoparticle (NP-1) of Cu-BHT. The overpotential of Cu-BHT toward HER shows an improved activity from 760 mV (NC-1) to 450 mV (NP-1) at a current density of 10 mA·cm–2. A Tafel slope of ∼95 mV·dec–1 and an exchange current density of 10–3 mA·cm–2 were achieved under optimized conditions. Density functional theory calculations suggest that the “Cu-edge site” on the (100) surface plays an important role...

Conjugated backbones play a fundamental role in determining the electronic properties of organic semiconductors. On the basis of two solution-processable dihydropyrrolo[3,4-c]pyrrole-1,4-diylidenebis(thieno[3,2-b]thiophene) derivatives with aromatic and quinoid structures, we have carried out a systematic study of the relationship between the conjugated-backbone structure and the thermoelectric properties. In particular, a combination of UV–vis–NIR spectra, photoemission spectroscopy, and doping optimization are utilized to probe the interplay between energy levels, chemical doping, and thermoelectric performance. We found that a moderate change in the conjugated backbone leads to varied doping mechanisms and contributes to dramatic changes in the thermoelectric performance. Notably, the chemically doped A-DCV-DPPTT, a small molecule with aromatic structure, exhibits an electrical conductivity of 5.3 S cm–1 and a high power factor (PF373 K) up to 236 μW m–1 K–2, which is 50 times higher than that of Q-DCM...

Bone nonunion has become one of the most severe sequelae of fractures, infections, bone tumors, or revision arthroplasty owing to its high morbidity and disability rate. Recently, bone nonunion has received considerable attention from plastic surgeons. There are different treatment methods for nonunion depending on its classification according to the etiology and pathological types. Bone tissue engineering provides advanced platforms for the treatment of bone nonunion via the use of material scaffolds with sufficient mechanical strength. Meanwhile, it promotes bone regeneration and osseointegration by the addition of various growth factors or drugs. This review describes in detail the classification and leading causes of nonunion, as well as the clinical treatment methods and basic research progress, including the design of metal and bioactive material scaffolds. Future challenges in engineering, material science, and three-dimensional printing are also summarized. This article may provide new perspectives of the clinical translation for the treatment of bone nonunion by understanding the pathogenic mechanism and the rational application of bioactive scaffolds. Keywords: Material, Bone nonunion, Classification, Pathological feature, Treatment progress

The local sustained release of bioactive substances are attracting increasing attention in bone tissue engineering, which is beneficial to bone tissue formation and helps to improve the bone ingrowth ability of a scaffold. Bisphosphonates (BPs), as a representative kind of osteoclast inhibitors, are proven to possess excellent osteogenic induction capability. Accordingly, various physical and chemical strategies are developed to functionalize bone tissue scaffolds with BPs to achieve controlled release profiles. Compared with traditional treatment modalities, local release of BPs from these composite scaffolds will contribute to continuous bone integration without the risk of many complications. This review explores the molecular mechanisms of BPs on bone metabolism and analyzes the appropriate concentrations of BPs that promote bone regeneration. The advanced BP loading strategies, implant modification technologies, and BP-loaded composite scaffolds based on different matrices are summarized. Finally, the latest advances and the future development of BP-modified scaffolds for enhanced bone regeneration are discussed. This article provides leading-edge design strategies of the BP-functionalized bone engineering scaffolds for improved bone repairability.

The use of metal shell is an effective method to solve electromagnetic interference caused by printed circuit board (PCB) of electronic equipment. Electromagnetic leakage mainly occurs at the junction of the upper metal shell and the lower metal shell. In order to reduce the electromagnetic interference caused by the electromagnetic leakage, the conductive adhesive is coated on the connection between the upper shell and the lower shell. In this paper, a simulation model of shielding effectiveness is established in CST STUDIO SUITE. It is mainly used to calculate the effects of conductivity and geometric size of conductive adhesives on shielding effectiveness. In the actual design process of electronic equipment, we can find a more economical combination of size and conductivity of conductive adhesives through the simulation of shielding effectiveness. The results can be used to guide the design of conductive adhesives to solve the electromagnetic compatibility problems of electronic equipment.

Polythiophene (PTh) with highly regular molecular structure is synthesized as nearly amorphous thin films by electrochemical methods in a BFEE/DTBP mixed medium (BFEE = boron fluoride ethyl ether; DTBP = 2,6-di-tert-butypyridine). The doping level and film morphology of PTh are modulated through adjusting the current density applied during the polymerization process. A combined analysis with solid-state NMR, FT-IR, and Raman spectra reveals the molecular structural regularity of the resulted PTh films, which leads to the highest electrical conductivity up to 700 S cm-1 for films obtained under an optimized current density of 1 mA cm-2 . By applying the self-heating 3ω-method, thermal conductivities are measured along the in-plane direction. A highly reduced Lorenz number of 6.49 × 10-9 W Ω K-2 and low lattice thermal conductivity of 0.21 W m-1 K-1 were extracted based on the analyses of the electrical and thermal conductivities according to the Wiedemann-Franz Law; the former is about one-third of the Sommerfeld value. Finally, the maximized ZT value can reach up to 0.10 under room temperature, which shows that the highly conducting polymers with less ordered structure is the practical direction for developing organic thermoelectric materials.

Nanocrystals of a 2D π-d conjugated copper bis(diselenolene) coordination polymer (Cu-BHS, BHS = benzenehexaselenolate) are synthesized via a simple homogeneous reaction between cupric ions and benzenehexaselenol (H6BHS). Its 2D extended hexagonal lattice is confirmed by powder X-ray diffraction, and further characterized by scanning electron microscopy, transmission electron microscopy, and X-ray photoelectron spectroscopy. The electrical conductivity measured on compressed powder sample reaches 110 S cm-1 at 300 K, which is among the highest value ever reported for coordination polymers. Furthermore, the intrinsic metallic characteristics of Cu-BHS are confirmed by ultraviolet photoelectron spectroscopy and band structure calculation.