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In this work, the hollow rectangular prism-like TiO2 (HRP-TiO2) mesocrystals with exposed {001} facets were synthesized via an in-situ hydrothermal process without introducing any additional hydrof...

The suboptimal carrier dynamics at the perovskite/electron transport layer has largely limited the further performance enhancement of the state-of-the-art inverted p-i-n structured perovskite solar cells. Herein, we discovered that a simple surface modification of the perovskite film by a trivalent metal halide salt, InBr3, could convert the doping levels of the top surface to be more n-type, which spontaneously formed an intriguing n/n+ homojunction between the bulk (weak n type (n) component) and the surface (more n-type (n+) component) in a monolithic perovskite film. This brought about synergistic advantages of the enlarged built-in electric field for facilitated charge separation, as well as optimized electronic energy level alignment and minimized electron injection barrier at the perovskite/C60 interface, leading to both accelerated charge extraction and suppressed interfacial charge recombination. Blade-coated inverted PSCs with n/n+ homojunctions achieved a high power conversion efficiency (PCE) of up to 22.2%, narrowing the efficiency gap with their conventional n-i-p counterparts. The InBr3 surface treatment also improved the operational stability to >1000 hours under light with 93% initial efficiency retained.

Two novel Ru(ii) polypyridyl complexes bearing imidazo-phenanthroline conjugated hydroxybenzoic acid groups were designed to enhance the tumor targeting ability as photosensitizers for photodynamic therapy. [Ru(bpy)2(phcpip)] (ClO4)2 (Ru-1) and [Ru(bpy)2(ohcpip)] (ClO4)2 (Ru-2) (bpy = 2,2'-bipyridine; phcpip = 2-(3-carboxyl-4-hydroxyphenyl) imidazo [4,5-f]phenanthroline; ohcpip = 2-(2-hydroxyl-3-carboxyphenyl) imidazo [4,5-f] [1,10] phenanthroline) were synthesized and their photodynamic antitumor activities were investigated. Both complexes displayed high photocytotoxicity toward cancerous cell lines HepG2, A549, MCF-7, and MDA-MB-231, but low photocytotoxicity toward normal cell lines GES-1 and Huvec. They were mainly localized at the nucleus of HepG2 cells after 24 h incubation, arrested the cell cycle at the G2/M phase and induced cancer cell apoptosis through reactive oxygen species (ROS) mediated pathways. Tumor targeting of the complexes is attributed to stronger molecular binding to DNA.

The in situ hydrolysis of acetontrile to acetate was utilized to construct crystal structures of lanthanide complexes for two analogous ligands, including dimeric [Ln2(Hhpip)2(OAc)6] (Ln = Eu, Tb, Dy; Hhpip = 2-(2-hydroxyphenyl)imidazo[4,5-f][1,10]phenanthroline) and two-dimensional polymeric [Tb(hnpip)(OAc)2]n, where hnpip− is the hydroxyl-deprotonated form of 2-(2-hydroxy-5-nitrophenyl)imidazo[4,5-f][1,10]phenanthroline acting as a tridentate bridging ligand. The former had a [Ln2(μ-η1:η2-OAc)2(μ-η1:η1-OAc)2(η2-OAc)2] subunit, whereas in the latter, [Tb2(μ-η1:η2-OAc)2] and [Tb2(μ-η1:η1-OAc)2] subunits are alternately aligned. The DMSO solution of [Eu2(Hhpip)2(OAc)6] and [Eu2(pip)2(OAc)6] (pip is 2-phenylimidazo[4,5-f][1,10]phenanthroline) were found to have a specific and prompt photoluminescence response to CO32− with significant emission colour change. The limit of detection was about 10 μM, depending on the complex and wavelength monitored.

Perovskite solar cells (PSCs) have been rapidly crowded into the emerging photovoltaic technology, exhibiting continuously boosted power conversion efficiencies (PCEs) over 25%. Despite the high PCE, the voltage loss (Vloss) of PSCs still need to be further reduced to achieve higher open-circuit voltage (Voc) and thus approaching its Shockley–Queisser limit. Great effort on minimizing the Vloss has been made by mainly suppressing non-radiative recombination in perovskite and/or relevant interface, maximizing initial radiative efficiency, and modifying energy level alignment in PSCs. However, a timely overview of the lowest Vloss values achieved and the strategies of suppressing Vloss for the PSCs based on the most prevalent perovskite compositions is still lacking. In this review, the definition and determining factors of Vloss are elucidated, and the state-of-the-art low Vloss values of PSCs based on various types of prevailing perovskites with variable bandgaps are comprehensively discussed. The strategies for suppressing Vloss of PSCs are highlighted, aiming to boost the fundamental understanding of related Vloss mechanisms. Finally, an insightful perspective on further suppressing the Vloss in PSCs is provided, targeting on achieving new record PCEs in PSCs.

Four new metal–organic frameworks (MOFs), [Co3(TCPB)2(CH3OH)4]·4DMF (1), [Cd3(TCPB)2(H2O)4]·3DMF·19H2O (2), [Mn3(TCPB)2(H2O)2(DMF)2]·2DMF (3), and [Zn2(μ3-OH) (TCPB)(H2O)(DEF)]·3DEF (4) (H3TCPB = 1,3,5-tri(4-carboxyphenoxy)benzene), have been successfully synthesized and structurally characterized. Structural analyses show that complexes 1–3 present two-dimensional (3,6)-connected kgd net topology with the Schlafli symbol of (43)2(46·66·83) based on linear trinuclear M3(COO)6 (M = Co, Cd, and Mn) secondary building units (SBUs) and display distinct one-dimensional (1-D) channels. Complex 4 (Zn-TCPB) exhibits a rare three-dimensional twofold interpenetrated (3,6)-connected rutile topology with the Schlafli symbol of (42·610·83) (4·62)2 based on the tetranuclear Zn4(μ3-OH)2(COO)6 clusters, which shows three different types of 1-D opening channels. In addition, as an anode material, the complex 4 (Zn-TCPB) electrode exhibits an irreversible high capacity in the first discharge process and a reversible lithium storage capacity of up to about 455 mA h g−1 at 0.1 A g−1 after 100 cycles. This might provide a new method for finding a promising candidate for the electrode materials in lithium-ion batteries.

Three series of lanthanide coordination polymers with formula [Ln2(PDC)3(H2O)2(DMF)]·4H2O (type I) (Ln = La 1, Pr 2, Sm 3), [(CH3)2NH2][Ln2(PDC)3(HCOO)(H2O)3]·2H2O (type II) (Ln = Tb 4, Ho 5) and [Ln(HPDC)3(H2O)2]·H2O (type III) (Ln = Er 6, Lu 7) (H2PDC = pyridine-3,5-dicarboxylic acid), have been successfully synthesized by the solvothermal reaction of pyridine-3,5-dicarboxylic acid (H2PDC) with the corresponding lanthanide nitrate. Compounds 1–3 are isomorphous and all crystallize in triclinic space group P, showing a 3D microporous framework of pcu topology with square channels along the b-axis. Isostructural compounds 4 and 5 show the same 2D layer network of (4,4)-grid in the monoclinic P21/c space group. Isomorphic 6 and 7 crystallize in the monoclinic Cc space group and present 1D zigzag chains which expand to a 3D supramolecular structure through π⋯π stacking interactions. The structural diversity of these three classes of compounds may be attributed to the effect of lanthanide contraction. They were characterized by infrared spectra (IR), elemental analysis (EA), thermogravimetric analysis (TGA), powder X-ray diffraction (PXRD), and X-ray single crystal diffraction. Furthermore, the catalytic properties of these compounds were investigated and experiments revealed that compounds 1–3 show size-selective catalytic performance for cyanosilylation reactions and could be reused without losing their catalytic activity.

Industrial wastewater and sewage are both important sources of heavy metals and metalloids in urban wastewater treatment plants (WWTPs). China has made great efforts to control heavy metal and metalloid pollution by setting discharge limits for WWTPs. There is, however, limited discharge data and no systematic methodology for the derivation of discharge limits. In this study, 14 heavy metals and metalloids (Hg, alkyl mercury, As, Cd, Cr, Cr6+, Pb, Ni, Be, Ag, Cu, Zn, Mn, Se) that are listed in the Discharge Standard of Pollutants for Municipal Wastewater Treatment Plant (GB 18918-2002) were selected for the analysis of discharge characteristics while using the supervised monitoring data from more than 800 WWTPs located in nine provinces in China. Of the 14 heavy metals and metalloids, all but alkyl mercury were detected in the discharge water. There was a high rate of detection of As, Cu, Mn, Se, and there were some samples that exceeded the standard concentrations of Cr, Cr6+, Pb, and Ni. Removal rates of Hg, As, Cd, Cr, Cr6+, Pb, Ni, Cu, Zn, Mn, and Se were higher than 40%, comparable to values from other countries. Hg and As were selected to analyze the influencing factors of effluent and derive discharge limits of WWTPs using a statistical method, because these two metals had more detected data than other metals. The study used supervised monitoring data from Zhejiang WWTPs with 99 for Hg and 112 for As. Based on the delta-lognormal distribution, the results showed that geographic location was significantly closely correlated with Hg (P = 0.027 &lt, 0.05) and As (P &asymp, 0 &lt, 0.05) discharge concentrations, while size (for Hg P = 0.695 &gt, 0.05, for As P = 0.088 &gt, 0.05) and influent concentration (R2 &lt, 0.5) were not. Derived Hg and As discharge limits suggest that it is necessary to establish stricter discharge limits for WWTPs, which is more consistent with the real-world situation in China. The study here comprehensively researches the discharge characteristics of heavy metals and metalloids in effluent of WWTPs in China, and developed for the first time in China heavy metals and metalloids discharge limits based on statistical methods. The results may inform special discharge limit settings for WWTPs in China.

Two GFPPS linked (+)-thalianatriene (1) and (−)-retigeranin B (2) sesterterpene synthase genes were identified from the genome of Arabidopsis thaliana. 1 possesses an unprecedented 11–6–5 tricyclic ring system, while 2 contains a characteristic 5–5–5–6–5 pentacyclic ring system. Their structures were determined by extensive NMR spectroscopy, chemical derivatization, and X-ray crystallography. The variable-temp NMR measurement of 3, a diepoxy-bearing derivative of 1, enables us to completely assign the NMR signals of the two conformers as 3a (67%, UUU) and 3b (33%, UUD). A plausible biosynthesis mechanism of 1 was proposed.

The treatment of domestic and industrial wastewater is one of the major sources of CH4 in the Chinese waste sector. On the basis of statistical data and country-specific emission factors, using IPCC methodology, the characteristics of CH4 emissions from wastewater treatment in China were analyzed. The driving factors of CH4 emissions were studied, and the emission trend and reduction potential were predicted and analyzed according to the current situation. Results show that in 2010, CH4 emissions from the treatment of domestic and industrial wastewater were 0.6110Mt and 1.6237Mt, respectively. Eight major industries account for more than 92% of emissions, and CH4 emissions gradually increased from 2005 to 2010. From the controlling management scenario, we predict that in 2020, CH4 emissions from the treatment of domestic and industrial wastewater will be 1.0136Mt and 2.3393Mt, respectively, and the reduction potential will be 0.0763Mt and 0.2599Mt, respectively. From 2010 to 2020, CH4 emissions from the treatment of domestic and industrial wastewater will increase by 66% and 44%, respectively.

Based on the statistical theory, the paper collected routine monitoring data for 3 years of 11 municipal wastewater treatment plants with secondary treatment or enhanced secondary treatment in a northern city in China, and analysis of the discharge concentration distribution of COD showed a Delta-lognormal distribution. On this basis, referring to the formulation methods of water pollutant discharge limits used in the USA, the paper studied and assessed the discharge status of COD of the municipal wastewater treatment plants in the city, including the daily maximum and the monthly average discharge status, and came to the conclusion that the daily maximum discharge status met the first grade A class discharge standard (50 mg · L(-1)) required by the Discharge Standard of Pollutants for Municipal Wastewater Treatment Plant (GB 18918-2002). Meanwhile, the assessment conclusion was obtained for the monthly average discharge status, and the conclusions were discussed. The assessment method and the conclusions in this paper might provide reference for formulation and revision of water discharge standards.