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Purpose: Transforming growth factor β (TGFβ) is a pleiotropic cytokine that affects tumor growth, metastasis, stroma, and immune response. We investigated the therapeutic efficacy of anti–TGFβ receptor II (TGFβ RII) antibody in controlling metastasis and tumor growth as well as enhancing antitumor immunity in preclinical tumor models.Experimental Design: We generated neutralizing antibodies to TGFβ RII and assessed the antibody effects on cancer, stroma, and immune cells in vitro. The efficacy and mechanism of action of the antibody as monotherapy and in combination with chemotherapy in suppression of primary tumor growth and metastasis were evaluated in several tumor models.Results: Anti–TGFβ RII antibody blocked TGFβ RII binding to TGFβ 1, 2, and 3, and attenuated the TGFβ-mediated activation of downstream Smad2 kinase, invasion of cancer cells, motility of endothelial and fibroblast cells, and induction of immunosuppressive cells. Treatment with the antibody significantly suppressed primary tumor growth and metastasis and enhanced natural killer and CTL activity in tumor-bearing mice. Immunohistochemistry analysis showed cancer cell apoptosis and massive necrosis, and increased tumor-infiltrating T effector cells and decreased tumor-infiltrating Gr-1+ myeloid cells in the antibody-treated tumors. Fluorescence-activated cell sorting analysis indicated the significant reduction of peripheral Gr-1+/CD11b+ myeloid cells in treated animals. Concomitant treatment with the cytotoxic agent cyclophosphamide resulted in a significantly increased antitumor efficacy against primary tumor growth and metastasis.Conclusions: These preclinical data provide a foundation to support using anti–TGFβ RII antibody as a therapeutic agent for TGFβ RII–dependent cancer with metastatic capacity. Clin Cancer Res; 16(4); 1191–205

Supplementary Data from Anti–Transforming Growth Factor β Receptor II Antibody Has Therapeutic Efficacy against Primary Tumor Growth and Metastasis through Multieffects on Cancer, Stroma, and Immune Cells

RON is a member of the c-MET receptor tyrosine kinase family. Like c-MET, RON is expressed by a variety of epithelial-derived tumors and cancer cell lines and it is thought to play a functional role in tumorigenesis. To date, antagonists of RON activity have not been tested in vivo to validate RON as a potential cancer target. In this report, we used an antibody phage display library to generate IMC-41A10, a human immunoglobulin G1 (IgG1) antibody that binds with high affinity (ED50 = 0.15 nmol/L) to RON and effectively blocks interaction with its ligand, macrophage-stimulating protein (MSP; IC50 = 2 nmol/L). We found IMC-41A10 to be a potent inhibitor of receptor and downstream signaling, cell migration, and tumorigenesis. It antagonized MSP-induced phosphorylation of RON, mitogen-activated protein kinase (MAPK), and AKT in several cancer cell lines. In HT-29 colon, NCI-H292 lung, and BXPC-3 pancreatic cancer xenograft tumor models, IMC-41A10 inhibited tumor growth by 50% to 60% as a single agent, and in BXPC-3 xenografts, it led to tumor regressions when combined with Erbitux. Western blot analyses of HT-29 and NCI-H292 xenograft tumors treated with IMC-41A10 revealed a decrease in MAPK phosphorylation compared with control IgG–treated tumors, suggesting that inhibition of MAPK activity may be required for the antitumor activity of IMC-41A10. To our knowledge, this is the first demonstration that a RON antagonist and specifically an inhibitory antibody of RON negatively affects tumorigenesis. Another major contribution of this report is an extensive analysis of RON expression in ∼100 cancer cell lines and ∼300 patient tumor samples representing 10 major cancer types. Taken together, our results highlight the potential therapeutic usefulness of RON activity inhibition in human cancers. (Cancer Res 2006; 66(18): 9162-70)

Supplementary Figure 3 from Therapeutic Implications of a Human Neutralizing Antibody to the Macrophage-Stimulating Protein Receptor Tyrosine Kinase (RON), a c-MET Family Member

Supplementary Figure 4 from Therapeutic Implications of a Human Neutralizing Antibody to the Macrophage-Stimulating Protein Receptor Tyrosine Kinase (RON), a c-MET Family Member

Supplementary Figure 6A and 6B from Therapeutic Implications of a Human Neutralizing Antibody to the Macrophage-Stimulating Protein Receptor Tyrosine Kinase (RON), a c-MET Family Member

Supplementary Figure 2 from Therapeutic Implications of a Human Neutralizing Antibody to the Macrophage-Stimulating Protein Receptor Tyrosine Kinase (RON), a c-MET Family Member

Supplementary Figure 1 from Therapeutic Implications of a Human Neutralizing Antibody to the Macrophage-Stimulating Protein Receptor Tyrosine Kinase (RON), a c-MET Family Member

Supplementary Figure 2 from Glioma Tumor Stem-Like Cells Promote Tumor Angiogenesis and Vasculogenesis via Vascular Endothelial Growth Factor and Stromal-Derived Factor 1

Supplementary Figure 5A and 5B from Therapeutic Implications of a Human Neutralizing Antibody to the Macrophage-Stimulating Protein Receptor Tyrosine Kinase (RON), a c-MET Family Member

Supplementary Figure 7A and 7B from Therapeutic Implications of a Human Neutralizing Antibody to the Macrophage-Stimulating Protein Receptor Tyrosine Kinase (RON), a c-MET Family Member

Supplementary Figure 1 from Glioma Tumor Stem-Like Cells Promote Tumor Angiogenesis and Vasculogenesis via Vascular Endothelial Growth Factor and Stromal-Derived Factor 1

Supplementary Figure Legends 1-2 from Glioma Tumor Stem-Like Cells Promote Tumor Angiogenesis and Vasculogenesis via Vascular Endothelial Growth Factor and Stromal-Derived Factor 1

Immune checkpoint blockade has shown significant clinical benefit in multiple cancer indications, but many patients are either refractory or become resistant to the treatment over time. HER2/neu oncogene overexpressed in invasive breast cancer patients associates with more aggressive diseases and poor prognosis. Anti-HER2 mAbs, such as trastuzumab, are currently the standard of care for HER2-overexpressing cancers, but the response rates are below 30% and patients generally suffer relapse within a year. In this study we developed a bispecific antibody (BsAb) simultaneously targeting both PD1 and HER2 in an attempt to combine HER2-targeted therapy with immune checkpoint blockade for treating HER2-positive solid tumors. The BsAb was constructed by fusing scFvs (anti-PD1) with the effector-functional Fc of an IgG (trastuzumab) via a flexible peptide linker. We showed that the BsAb bound to human HER2 and PD1 with high affinities (EC50 values were 0.2 and 0.14 nM, respectively), and exhibited potent antitumor activities in vitro and in vivo. Furthermore, we demonstrated that the BsAb exhibited both HER2 and PD1 blockade activities and was effective in killing HER2-positive tumor cells via antibody-dependent cellular cytotoxicity. In addition, the BsAb could crosslink HER2-positive tumor cells with T cells to form PD1 immunological synapses that directed tumor cell killing without the need of antigen presentation. Thus, the BsAb is a new promising approach for treating late-stage metastatic HER2-positive cancers.

Asthma is characterized by airway hyperresponsiveness and inflammation, as well as underlying structural changes to the airways. Interleukin-4 (IL-4) is a key T-helper type 2 (Th2) cytokine that plays important roles in the pathogenesis of atopic and eosinophilic asthma. We developed a novel humanized anti-IL-4Rα antibody that can potently inhibit IL-4/IL-13-mediated TF-1 cell proliferation. Using monocytes isolated from human peripheral blood mononuclear cells (PBMCs), we revealed a critical role of CD32 in modulating the immune responses of monocytes in response to blockade of IL-4Rα signaling pathway. We, therefore, devised a new strategy to increase the efficacy of the anti-IL-4Rα monoclonal antibody for the treatment of asthma and other atopic diseases by co-engaging CD32 and IL-4Rα on monocytic cells by choosing IgG classes or Fc mutations with higher affinities for CD32. The antibody with selectively enhanced affinity for CD32A displayed superior suppression of IL-4-induced monocytes’ activities, including the down-regulation of CD23 expression. Intriguingly, further analysis demonstrated that both CD32A and CD32B contributed to the enhancement of antibody-mediated suppression of CD23 expression from monocytes in response to blockade of IL-4Rα signaling. Furthermore, inhibition of IgE secretion from human PBMC by the antibody variants further suggests that the complex allergic inflammation mediated by IL-4/IL-4Rα signaling might result from a global network where multiple cell types that express multiple FcγRs are all involved, of which CD32, especially CD32A, is a key mediator. In this respect, our study provides new insights into designing therapeutic antibodies for targeting Th2 cytokine-mediated allergic pathogenesis.

IL-33, the ligand for ST2, is a member of IL-1 family. IL-33 was described to activate many immune cell types involved in type-2 immunity and allergic inflammation. Here we describe a novel anti-IL33 humanized monoclonal antibody, SSGJ-621, which bound IL-33 with high affinity and blocked the interaction between IL-33 and ST2. Our study has shown that SSGJ-621 was capable of effectively neutralizing IL-33-induced IL-6 secretion from HUVECs and IL-33-dependent IFNγ production in PBMCs and NK cells, suggesting a role that IL-33 might be involved in Th1-type of immunity. In addition, SSGJ-621 also exhibited potent inhibitory effects on IL-33 induced IL-5 and IL-13 production in KU812 cells. In vivo study demonstrated that SSGJ-621 can inhibit the activation of splenocytes in spleen and the production of eosinophils and IL-5 in peripheral blood. Thereby, our results highlight the dual functions of IL-33 in promoting Th1 and Th2 immune responses and SSGJ-621 has potentials to treat not only chronic inflammatory diseases induced by IL-33, but also cancers by favoring Th1 antitumor immunity in the tumor microenvironment. Citation Format: Xuesai Zhang, Qingrou Li, Cui Liu, Le Zhao, Lujie Wang, Lan Deng, Wei Xu, Hongli song, Zhenping Zhu, Haomin Huang. A novel anti-IL33 antibody that neutralized Th1-type and Th2-type pro-inflammation responses induced by IL-33/ST2 axis pathway [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 6191.

Highlights • The anti-PD1 x anti-EGFR bispecific antibody (BsAb) exhibited all in-vitro bioactivities comparable to that of the parental mAbs and showed anti-tumor efficacies of each of the two arms on par with the mAbs in-vivo. • The anti-PD1 x anti-EGFR bispecific antibody (BsAb) retained full ADCC towards cancer cells but not to T cells. Thus the BsAb is capable of killing tumor cells via ADCC while sparing T cells for T cell-induced anti-tumor immunity. • The anti-PD1 x anti-EGFR bispecific antibody (BsAb) exhibited significantly stronger tumor cell killing effects in the presence of PBMC relative to that of combination of cetuximab with an anti-PD1 mAb, 609A., We developed a strategy to combine conventional targeted therapy with immune checkpoint blockade using a tumor-targeting bispecific antibody (BsAb) to treat solid tumors. The BsAb was designed to simultaneously engage a tumor-associated antigen, epidermal growth factor receptor (EGFR), and programed cell death protein 1 (PD1). In addition to its direct anti-tumor activity via EGFR inhibition, the BsAb mediated efficient antibody-dependent cellular cytotoxicity (ADCC) and activated T cell antitumor im munity through blockade of PD1 from interacting with its counterpart, programed cell death ligand 1 (PDL1). Further, the BsAb exhibited a potent direct tumor cell killing activity in the presence of PBMC, most likely, via activating and, at the same time, physically engaging T cells with tumor cells. Taken together, we here illustrate a new strategy in the design and production of novel BsAbs with enhanced therapeutic efficacy through both direct tumor growth inhibition and T cell activation via tumor-targeted immune checkpoint blockade.

Precious metal-free hybrid photocatalysts with low cost and high efficiency of photocatalytic H2 evolution are of great significance for clean energy. Herein, we report that oxygen-incorporation in Co2P, a noble metal-free co-catalyst used for forming a hetero-structure photocatalyst CdS/o-Co2P, greatly improves the efficiency and durability for photocatalytic hydrogen production from water. Regulating the kinetics of water reduction by different oxygen incorporation levels (determined by phosphorization time) was investigated to optimize the activity of photocatalytic H2 evolution. The intimate interaction between the CdS nanorods and cocatalyst o-Co2P enhances the separation of the photo-generated electron–hole pairs. Consequently, the optimal loading content of o-Co2P is 5 wt% for CdS, phosphorization time is 80 min, giving a photocatalytic H2 production rate of 184.48 mmol g−1 h−1, and the apparent quantum yield at 420 nm over CdS/o-Co2P-5 wt% reaches 22.17%. This study provides a simple method for constructing low cost and high performance photocatalysts, which enhance photocatalytic H2 evolution.

TiO2 with exposed (001) facets were composited with CdS nanorods to construct 2D/1D heterojunction. As comparison, P25 with mainly exposed (101) facets were employed to combine with CdS nanorods. The 2D/1D heterojunction of TiO2 nanosheets and CdS nanorod displayed 3.7 times higher hydrogen generation than that of P25/CdS composites. The results indicated that TiO2 with exposed (001) facets were favorable for enhancing the photocatalytic activity of CdS via optimizing the heterojunction between TiO2 and CdS. Photoluminescence and photoelectrochemical characteristics results demonstrated that the 2D-TiO2/1D-CdS heterojunction exhibits higher separation efficiency of photoinduced carriers and superior electron transfer ability. This work exemplifies that heterojunction modification is an effective strategy to improve the efficiency of the photocatalyst composites.

The dehydrogenation and conversion of methanol into 1,1-dimethoxymethane (DMM) was achieved over noble metal-free photocatalyst CdS/Ni2P under visible light. This photocatalytic process for methanol-to-H2 and DMM conversion is efficient and atom economic, with an optimal rate and selectivity of DMM of 188.42 mmol g−1 h−1 and 82.93%, respectively. This work supplies a new green approach for the direct efficient conversion of methanol into DMM and provides a promising avenue for sustainable bio-methanol applications.

Designing cost-effective, highly efficient and stable electrocatalysts for oxygen evolution reaction is of paramount importance. Although extensive studies have focused on the relatively cheaper 3d transition metal oxide catalysts, the effect of trimetallic composites on the catalytic ability still remains elusive. Herein, we selected FeCo catalyst as the platform and investigated the catalytic activity of trimetallic composites, which were synthesized by incorporating Mo, W or Ni into the FeCo catalyst. The experimental results evidenced that FeCoMo/CP exhibited high catalytic activity towards water oxidation in alkaline solution, which required an overpotential of only ∼270 mV. Such impressive catalytic performance of FeCoMo/CP can be attributed to the fact that the introduction of Mo appreciably modulated the electronic structure of the Fe and Co centers, leading to an enhancement in intrinsic active sites. Benefiting from the tight contact with the highly conductive carbon paper substrate, FeCoMo/CP showed excellent stability up to 120 h. These results indicate that the surface engineering of FeCo-based catalysts by incorporating non-noble metals is a rational strategy to promote the performance of electrocatalysts.

This study aims to develop an effective and inexpensive oxygen evolution reaction (OER) electrocatalysts for efficient water splitting. Cu2O nanoparticles coated with carbon (Cu2O@C) were successfully synthesized by photocatalytic method. As a novel non-noble-metal OER catalyst, the Cu2O@C exhibited excellent OER efficiency with an onset overpotential of 250 mV and a Tafel slope of 63 mV decade−1. This catalyst maintained its catalytic activity for at least 100 h and required only an overpotential of 330 mV to attain a current density 10 mA cm−2GEO. During OER catalysis, the carbon shell served as a conducting media to quicken the charge transfer and as a protective layer to enhance the phase stability and prevent the aggregation of Cu2O nanoparticles.

A series of new Zn-porphyrin dyes (LYD-1 similar to 5) with various substituted and anchoring groups have been designed, fabricated and fully characterized by nuclear magnetic resonance (NMR), ultraviolet visible (UV-vis), and High Resolution Mass spectroscopy (HRMS). The solar cells sensitized by new dyes have been systematically investigated by photoelectrochemical experiments of current density-voltage (J - V), incident monochromatic photon-to-electron conversion efficiency (IPCE) and electrochemical impedance spectra (EIS). The results show that the performance of DSC devices is deeply affected by the substituted and anchoring groups of dyes. The best solar cell sensitized by LYD-5 with alkoxyl donors and salicylic acid exhibits excellent photovoltaic conversion efficiency of 8.5% compared with 7.7% of YD2-o-C8-based solar cell under the same conditions. Their structural features and electron distribution of HOMOs and LUMOs are calculated computationally using a DFT method at the level of B3LYP/6-31G(d)/LANL2DZ.

We report new insights into the photoelectrochemical reduction of CO 2 in a photoelectrochemical system, which is assembled from a nickel foam covered with TiO 2 modified by covalent ligands as photocathode and BiVO 4 as photoanode. These photoelectrocatalytic cells generate mainly methanol as a product in the liquid phase. Our results show that imine-functionalized TiO 2 /Ni has the highest activity. The formation rate of methanol in this excellent cell is up to 153 μM/h · cm 2 , which is about 15 times higher than that of the TiO 2 /Ni electrode. If the Faradaic efficiency is considered as 100%, the light quantum efficiency of this cell reaches 1.2%, that is two times better than that of plants. Isotopic labeling experiments with 13 CO 2 confirm that the detected products are produced exclusively by the reduction of CO 2 and water splitting.

TiO2-Ni(OH)2/CNT/CdS hybrid photocatalyst have been fabricated by a facile synthesis method under room temperature. CdS sensitized TiO2 hybrid photocatalysts with Ni(OH)2 and CNT cocatalysts anchored on TiO2 surface caused significant enhancement in photocatalytic H2 production rate in lactic acid aqueous solution under visible light irradiation. The optimized TiO2-Ni(OH)2/CNT/CdS shows high photocatalytic activity in H2 genneration of 12 mmol g−1 h−1 exceeding TiO2-Ni(OH)2/CdS and TiO2/CNT/CdS which can be attributed to the combined effect of Ni(OH)2 and CNT. Photoluminescence and photoelectrochemical characteristics results demonstrated that the introduction of Ni(OH)2 and CNT displays synergetic effect in promoting the separation efficiency of the photoinduced electron-hole pairs. A scheme of charge transfer over the hybrid photocatalyst is proposed indicating the synergetic effect of Ni(OH)2 and CNT on promoting electron transport at the heterojunction surface between TiO2 and CdS. The performance of the stability of the TiO2-Ni(OH)2/CNT/CdS was tested in the presence of lactic acid under visible light irradiation. The system gives no loss in the hydrogen production after several recycling experiments confirming that the composite is stable and anti-photocorroded.

The photoelectrocatalytic (PEC) reduction of CO2 to chemical fuels was achieved by utilizing the multi-functionalized TiO2 film photocathodes. On the surfaces of TiO2 films, Pd nanoparticles were introduced to catch protons, molecules of Eosin Y disodium salt were embedded to absorb solar energy, and four different amine ligands were immobilized to capture and activate CO2. In the novel PEC cells, multi-functionalized TiO2 and Co-Pi/W:BiVO4 films were served as photocathode and the counter electrode, respectively. It was found that methanol was the major liquid product. Besides, some ethanol and acetone can be detected as well. The maximum formation rate and the highest selectivity of methanol were 43.6 μM cm−2 h−1 and approximately 100%, respectively. The Faradaic efficiencies of the PEC cells can exceed 1000% with the aid of photoelectrons. The 13CO2 labeling experiments verify that methanol and carbon monoxide are derived from CO2.

Selective oxidation of alcohols to highly valued chemicals in a clean manner (e.g., with water as a solvent and O2 or H2O2 as the primary oxidant) is the subject of considerable research attention. This paper presents a simple and environmentally friendly approach for the selective oxidation of isopropanol to pinacol C6 (2,3-dimethyl-2,3-butanediol) in water with hydrogen peroxide (H2O2) through UV irradiation under mild conditions. A selectivity of 82–95% is achieved at H2O2 feeding rates below 4 mL h−1. The introduction of TiO2 nanotubes can further accelerate isopropanol conversion and enhance pinacol C6 formation. The highest formation rate of pinacol C6 and the highest conversion rate of isopropanol are 29.4 and 71.4 mmol h−1, respectively. The proposed strategy provides a green solution for the synthesis of aliphatic pinacol and offers a new design for the construction of C–C bonds with alphatic alcohol.

Water oxidation and reduction over semiconductor-based photocatalysts intrinsically occur at different spatial sites. Modulation of the reaction sites and charge transfer between them are logically important in speeding up the reaction. Here, we demonstrate that divorcing a CdSe–CdS–Pt donor–acceptor system on different surface sites of TiO2 can significantly increase the H2 generation rate. The increase is derived from an effective reset of water oxidation and reduction sites. Widening of the site distance by employing a TiO2 membraniform acceptor effectively decreases the electron–hole recombination especially for a membrane of TiO2 nanotube arrays. The oriented charge transfer characteristic of TiO2 nanotube arrays benefits long-range electron transport, thereby increasing the electron lifetime and reaction rate. When more conductive carbon nanotube arrays serve as an electron acceptor to replace TiO2, the electron transport is greatly improved, resulting in an ultrahigh H2 generation rate of 1270 mmol g−1 h−1. This work provides a basis for the design and construction of highly efficient photocatalysts through rational modulation of reaction sites and charge transport.

The morphological characteristics of a photocatalyst is central to its photocatalytic activity for solar energy conversion. Herein, Pt–ZnS/CdS composites comprising ZnS nanosheets, embedded via the geometry and size modulation and tuning of band gap of CdS with 0D, 1D or 2D structure, were investigated for solar hydrogen production. The photoactivity results indicate that the shape and morphology of CdS in the Pt–ZnS/CdS heterojunction play a pivotal role in affecting the photocatalytic performance. CdS with a 1D structure deposited on porous Pt–ZnS nanosheets endow the heterojunction with increased efficiency for the separation and transport of photoinduced electron–hole pairs. The proposed mechanism for the boosted suppression of charge recombination was further confirmed by the transient photocurrent response and photoluminescence.

The conversion of carbon dioxide into useful chemicals is a prospective strategy for alleviating the greenhouse effect and the depletion of energy. Herein, we report an artificial photosynthetic system composed of a photoanode and a photocathode comprised of NRx@TiO2 functionalized with Nile red via covalent linkage or Pd/NRx@TiO2 with additional palladium nanoparticles. The new Nile red derivatives and organic–inorganic composite electrodes were steadily prepared and well characterized using NMR, HRMS, UV-vis, FTIR, TEM, XPS, XRD and SEM. Methanol and oxygen were the products that could be detected in the liquid and gas phase. The main active species in this artificial photosynthesis system were proven using EPR spectroscopy to be hydroxy radicals releasing O2 gas via H2O2. Moreover, the carbon source of methanol was validated using a 13CO2 labeling experiment; 18O2 was determined to come from H2O using GC-MS. The optimal photoelectrocatalytic CO2 reduction was carried out using Pd/NR2@TiO2 as the working electrode yielding methanol at a rate of 106 μM h−1 cm−2 with high light quantum efficiency (Φcell = 0.95).

Facile carbon–carbon bond formation was achieved through the dehydrogenation coupling of acetone at the α-position. Using the H2O2/UV-light system, the acetonyl radicals that were formed from the selective cleavage of the α-C–H bond of acetone underwent a C–C coupling reaction. By modulating the instantaneous concentration of hydrogen peroxide, the direct C–C coupling of acetone was achieved. Moreover, the selectivity and generation rate of 2,5-hexanedione reached 67.4% and 8.6 mmol h−1, respectively.

To understand the mechanism of the photocatalytic direct synthesis of 1,1-diethoxyethane (DEE) from ethanol is vital for enhancing the reaction efficiency. Based on photocatalytic data of different phase TiO2 and F–TiO2 catalysts, radical trapping data, and GC-MS data, we proposed a photocatalytic mechanism for the preparation of both DEE in neat ethanol and 2,3-butanediol (2,3-BD) in ethanol–H2O using photocatalytic methods. In neat ethanol, hydroxyl isn’t involved in the catalytic cyclic process but hydroxyl has an indirect site-holding effect, thus leading to more hydroxyl groups with higher activity. In ethanol–H2O, although the strong oxidant ˙OH radical is involved, fewer OH groups lead to higher selectivity of 2,3-BD. The interaction of the reactant/solvent with the surface group of the catalyst is important in the activity and selectivity of photocatalytic reactions. This finding gives fundamental insight into the role of TiO2 surface hydroxyl in the photocatalytic dehydrogenation process of alcohols and opens a promising path to obtaining both high selectivity and high conversion in TiO2-based photocatalytic activity.

New dithiafulvenyl-pi-phenothiazine dyes have been devised and prepared for dye-sensitized solar cells. Various pi-spacers have been successfully introduced into the skeleton of dithiafulvenyl and phenothiazine unit to generate novel D-pi-D-A dyes (DPP-1 similar to 4). All dyes have been characterized with NMR, HRMS, UV-vis and fluorescence spectra, and taken into cyclic voltammetry measurements. The devices of new dyes have been determined by photoelectrochemical experiments (IV, IPCE and EIS), in which, solar cell of DPP-4 with biphenyl ring pi-spacer enhances obviously its photoelectric conversion efficiency to 7.66% reaching 94% of N719-based standard cell and displays good long-term stability with quasi-solid-state electrolyte. Density functional theory (DFT) calculations of new dyes provide further insight into the molecular geometries and the impacts of the torsion angles on their photovoltaic performance. Large dihedral angles in DPP dyes induce good charge separation for efficient unidirectional flow of electron from donor to acceptor. (C) 2016 Elsevier B.V. All rights reserved.

Three-dimensional (3D) graphene frameworks (GFs) loading CuS nanocrystals composite (GFs–CuS) are prepared by an in-situ hydrothermal process. We find that 3D graphene frameworks exhibit an excellent supporter for even growth and good distribution of CuS nanocrystals. Such 3D architecture composite could provide multi-direction channels that greatly facilitate electron transport and ion diffusion as well as offer more accessible catalytic active sites. These intrinsic factors are essential for an efficient counter electrode (CE) of quantum dot-sensitized solar cells (QDSSCs). As expected, the CdS/CdSe QDSSCs based on GFs-CuS CE achieves a high power conversion efficiency of 5.04%, which is higher than those of the traditional Pt CE (3.18%), GFs CE (3.60%) and CuS CE (3.75%), even better than 2D graphene–CuS composite CE (4.17%). The electrochemical impedance spectra and Tafel polarization curve analysis reveal that the 3D GFs–CuS composite counter electrode exhibits the lower charge-transfer resistance, faster ion diffusion ability and the higher electrocatalytic activity in comparison with the Pt, GFs, CuS and 2D graphene–CuS electrodes. Furthermore, the GFs–CuS CE exhibits excellent stability, demonstrating its promising potential application as effective counter electrode material in QDSSCs.

Due to the limited electronic conductivity, the application of many metal oxides that may have attractive (photo)-electrochemical properties has been limited. Regarding these issues, incorporating low-dimensional conducting scaffolds into the electrodes or supporting the metal oxides onto the conducting networks are common approaches. However, some key electronic processes like interfacial charge transfer are far from being consciously concerned. Here we use a carbon-TiO2 contact as a model system to demonstrate the electronic processes occurring at the metal-semiconductor interface. To minimize the energy dissipation for fast transfer of electrons from semiconductor to carbon scaffolds, facilitating electron tunneling while avoiding high energy-consuming thermionic emission is desired, according to our theoretical simulation of the voltammetric behaviors. To validate this, we manage to sandwich ultrathin TiO2 interlayers with heavy electronic doping between the carbon conductors and dopant-free TiO2. The radially graded distribution of the electronic doping along the cross-sectional direction of carbon conductor realized by immobilizing the dopant species on the carbon surface can minimize the energy consumption for contacts to both the carbon and the dopant-free TiO2. Our strategy provides an important requirement for metal oxide electrode design.

Tartronic acid (TA) is a high value-added chemical widely used as a pharmaceutical product and a preservative; however, its synthesis technology is complicated and high cost. In this study, aqueous solutions of lactic acid were photochemically converted into TA via green oxidation by using hydrogen peroxide (H2O2).

A new series of phenothiazine-based D–A–π–A dyes PZ-1–4 have been designed, synthesized and fully characterized by 1H, 13C NMR, HRMS, UV-vis, fluorescence, and cyclic voltammetry spectroscopy. Benzothiadiazole was introduced into the D–π–A dyes as an additional acceptor. Various donors and new π-spacers have been connected to phenothiazine skeleton on opposite sides to generate PZ-2–4 dyes. The DSSC devices have been systematically investigated by photoelectrochemical experiments, the solar cell of PZ-4 with a simple hexyloxyphenyl group achieves the highest photoelectric conversion efficiency of 6.35%. Density functional theory (DFT) calculation results demonstrate that the large dihedral angle (36.3°) between the π-spacer and phenothiazine in PZ-4 induces better charge separation. Its largest semicircle at intermediate frequencies in electrochemical impedance spectroscopy (EIS) prevents the recombination of photoelectrons injected into the titanium dioxide (TiO2) conductive band with I3− in electrolyte, which might be caused by the blocking interaction of the hexyloxy group dye.

Back reactions were suppressed effectively by double blocking barrier, organic molecules and ZnS on the photoanode of quantum dot (QDs) sensitized solar cells (QDSSCs), thereby achieving higher conversion efficiency. In this work, four different organic molecules were applied in QDSSCs, the efficiency increased two-fold from 2.21% to 4.25% when co-modifications with 4-tert-butyl pyridine (TBP) and ZnS were sequentially applied. The incident photon-to-current efficiency (IPCE) and parameters obtained from impedance spectroscopy (IS) such as recombination resistance (Rrec), chemical capacitance (Cμ), and electron lifetimes were consistent with the measured photovoltaic performance. We speculated that organic molecules mainly inhibit the charge recombination of the injected electrons in TiO2 with electrolyte, because of its steric factor and the electron-donating property of the tert-butyl group. The selective site of modification has been tested for assessing the dominant mechanism underlying the improvement of solar cell characteristics.

The hydrogenative cyclization of levulinic acid (LA) into γ-valerolactone (GVL) is an attractive route toward the use of renewable bio-sources but it normally suffers from the consumption of H2. In this study, we report that an intermolecular hydrogen transfer from isopropanol to LA can be realized efficiently under photocatalytic conditions over gold-loaded TiO2 catalysts. In this manner, isopropanol is dehydrogenated as acetone and pinacol with the total selectivity of >99%, whereas LA is hydrogenated and cyclized as GVL with the selectivity of up to 85%. In this reaction process, the production of GVL is mediated with hydrogenated dehydration of LA into an acetyl propionyl radical, which is further hydrogenated and cyclized as GVL. This hydrogenation–dehydrogenation coupling process provides an atom-economical green way for the conversion of LA into GVL.

Theoretically, selective C–H manipulation in ethanol can result in a direct C–C coupling synthesis of 2,3-butanediol (2,3-BDO). However, this process is typically extremely difficult to achieve because of the high complexity of the involved chemical bonds. In this work, we determine that hydroxide radicals generated from the photolysis of H2O2 can selectively attack the α-hydrogen atom in ethanol aqueous solutions and crack the C–H bond to produce hydroxyethyl radicals, which subsequently undergo C–C coupling to form 2,3-BDO. This selective C–H breakage is determined by the reaction rate, which is primarily controlled by the local H2O2 concentration at a given irradiation intensity. At a moderate reaction rate of ethanol (37 mmol h−1), the 2,3-BDO selectivity reaching as high as 91% can be obtained. The introduction of a catalyst can further increase ethanol conversion and enhance the 2,3-BDO formation rate by controlling the reaction rate. This result provides an environment-friendly approach to convert bio-ethanol directly to 2,3-BDO and to manipulate a single bond selectively in complex bonding situations.

Substrates are normally required in the chemical synthesis of graphene to enhance its formation. However, removing substrates in the post purification stage is difficult, during which harsh reagents are used and the substrates are usually consumed undesirably. In this paper, we report that universal sodium carbonate (Na 2 CO 3 ) particles can effectively promote the construction of well-structured graphene frameworks based on a quick thermal decomposition of fumaric acids. Notably, the Na 2 CO 3 particles are easily separated from graphene through a simple and green method, namely, washing with water at room temperature. Together with the reused characteristic of the recovered Na 2 CO 3 particles, this approach is undoubtedly beneficial to the low-cost and clean synthesis of graphene. Benefiting from the framework structure, the as-synthesized graphene exhibits excellent performance in the supercapacitor. The specific capacitance of the GFs-modified electrode was calculated to be 242 F g −1 at 0.5 A g −1 , which was almost twice that of the RGO-modified electrode (134 F g −1 ). More importantly, the GFs-modified electrode maintained 92.6% retention of its initial specific capacitance (from current density of 0.5 to 16 A g −1 ), which was much higher than that of 2D graphene-modified electrode.

Graphene with a cellular framework structure (GFs) exhibits unique advantages that facilitate quasi-isotropic electron conduction, promote ion diffusion, and induce transport. GFs can act as an ideal support to uniformly disperse platinum (Pt) nanoparticles to better catalyze molecular or ionic reactions, which are intrinsically important for an effective counter electrode (CE) in dye-sensitized solar cells (DSSCs) systems. The power conversion efficiency of optimized DSSCs with GFs CE is 6.15%, which is comparable to that of the conventional Pt CEs (6.71%) and markedly than that of 2D graphene sheets CE (3.60%). More importantly, the GFs-Pt composite CEs could achieve an efficiency of 7.26%. The dynamic discipline behind the improved performance of GFs-based CEs in DSSCs is systematic investigated by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and Tafel polarization analysis, revealing that the better diffusion coefficient of the I3− ion and lower charge transfer resistance at CE interface result in the higher efficiency of GFs based solar cells.

Converting renewable biomass and their derivatives into chemicals and fuels has received much attention to reduce the dependence on fossil resources. Photocatalytic ethanol dehydrogenation-acetalization to prepare value-added 1,1-diethoxyethane and H2 was achieved over non-precious metal CdS/Ni-MoS2 catalyst under visible light. The system displays an excellent production rate and high selectivity of 1,1-diethoxyethane, 52.1 mmol g-1 h-1 and 99.2 %, respectively. In-situ electron spin resonance, photoluminescence spectroscopy and transient photocurrent responses were conducted to investigate the mechanism. This study provides a promising strategy for a green application of bioethanol.