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The combustion of biomass fuel boilers not only produces inorganic pollutants such as carbon oxides, nitrogen oxides, sulfur compounds, but also organic pollutants such as VOCs and PAHs, which directly affect the global biogeochemical cycle and atmospheric changes. Compared with foreign countries, there is relatively less research and related standards on the emission of organic pollutants from biomass fuel boilers in China. Therefore, it is necessary to study the emission characteristics of organic pollutants from biomass boilers, which can provide reference for the establishment of organic pollutant emission standards for biomass fuel boilers in China.The emission characteristics of volatile organic compounds(VOCs) and polycyclic aromatic hydrocarbons(PAHs) organic pollutants in the flue gas of three typical biomass-fired boilers in Chongqing were studied, and the emission concentrations of particulate matter, sulfur dioxides(SO2), and nitrogen oxides(NOX) were measured.The results show that the sulfur dioxide emissions from the three types of biomass-fired boilersrs are lower than the local standards in Chongqing, while nitrogen oxides and particulate matter have a phenomenon of exceeding the emission limits of the local standards in Chongqing. The main components of VOCs emitted from biomass powder and biomass particle combustion are OVOCs and aromatic hydrocarbons, while the main components of VOCs emitted from wood biomass combustion are alkynes. The gas-solid distribution pattern of PAHs during the combustion of three types of biomass is basically consistent. Low ring PAHs are mainly enriched in the gas phase, while medium and high ring PAHs are mainly enriched in particulate matter.

In order to improve air quality and reduce haze, Chongqing has raised the nitrogen oxide emission requirements of gas industrial boilers, reduced the emission limits, and promoted a large number of low-nitrogen transformations of industrial boilers in Chongqing. In this paper, the main generation mechanism of nitrogen oxides and different technical schemes of low nitrogen transformation were introduced. Six representative industrial boilers were selected to carry out low nitrogen transformation based on FGR technology, and nitrogen oxide emission under the reference oxygen content, smoke exhaust temperature, thermal efficiency and actual output of boilers before and after the transformation were compared and tested. The test results show that the actual output of industrial boilers can be reduced and the energy consumption of boilers can be increased by using FGR low nitrogen technology.

Due to its soft lattice characteristics, all‐inorganic cesium lead halide (CsPbI3‐xBrx) perovskite is vulnerable to external environmental stress such as moisture, polar solvent, illumination. resulting in structural defects (VI, Ii, etc.) and ion mobility. However, most of the prior arts focus on short‐term and static passivation, which has a negligible effect on defects formed during solar cell operation. Herein, a photoisomerizable molecule, 1,3,3‐trimethylindolino‐8′‐methoxybenzopyrylospiran (OMe‐SP), exhibiting light‐driven pre‐isomeric (SP) and post‐isomeric (PMC) configurations, is employed as an interfacial protective layer on top of CsPbI3‐xBrx. The present strategy not only effectively suppresses migration of halogen ions, but also enables sustainable passivation of defects, thereby significantly reducing interfacial charge recombination and retarding perovskite degradation. Consequently, the OMe‐SP‐modified perovskite solar cells (PSCs) exhibit superior stability, maintaining 91% of their initial efficiency after aging 1032 h under maximum power point (MPP) tracking and continuous one sun illumination. Meanwhile, the OMe‐SP‐modified cell also achieves an impressive power conversion efficiency of 22.20%, which stands as the highest among all‐inorganic perovskite solar cells. Overall, the implementation of this robust strategy provides sustainable defect passivation and continuous suppression of ion migration for achieving both high PCE and stable inorganic perovskite. [ABSTRACT FROM AUTHOR]

The characteristics of the soft component and the ionic‐electronic nature in all‐inorganic CsPbI3‐xBrx perovskite typically lead to a significant number of halide vacancy defects and ions migration, resulting in a reduction in both photovoltaic efficiency and stability. Herein, we present a tailored approach in which both anion‐fixation and undercoordinated‐Pb passivation are achieved in situ during crystallization by employing a molecule derived from aniline, specifically 2‐methoxy‐5‐trifluoromethylaniline (MFA), to address the above challenges. The incorporation of MFA into the perovskite film results in a pronounced inhibition of ion migration, a significant reduction in trap density, an enhancement in grain size, an extension of charge carrier lifetime, and a more favorable alignment of energy levels. These advantageous characteristics contribute to achieving a champion power conversion efficiency (PCE) of 22.14 % for the MFA‐based CsPbI3‐xBrx perovskite solar cells (PSCs), representing the highest efficiency reported thus far for this type of inorganic metal halide perovskite solar cells, to the best of our knowledge. Moreover, the resultant PSCs exhibits higher environmental stability and photostability. This strategy is anticipated to offer significant advantages for large‐area fabrication, particularly in terms of simplicity. [ABSTRACT FROM AUTHOR]

Element doping/alloying is a common strategy to tune the electrical and thermal transports of thermoelectric (TE) materials, but the doping/alloying limit of foreign elements in many TE materials is usually very low, bringing a great challenge to improve the TE performance. In this work, beyond the classic principle of “like dissolves like,” it is found that choosing the compound with a severely distorted lattice and diversified chemical bonding as the matrix also facilitates achieving a high doping/alloying limit. Taking ductile semiconductors as an example, this work shows that gold (Au) element is nearly immiscible in Ag2S and Ag2Te, but has a relatively high alloying limit in complex Ag2S0.5Te0.5 meta‐phase. Au in Ag2S0.5Te0.5 significantly decreases the carrier concentration and improves the TE performance, but scarcely changes the mechanical properties. Consequently, Ag1.99Au0.01S0.5Te0.5 demonstrates both a high figure‐or‐merit of 0.95 at 550 K and extraordinary room‐temperature ductility. This work offers an effective and general strategy to develop stabilized doped/alloyed TE materials. [ABSTRACT FROM AUTHOR]

Gallium oxide (β-Ga2O3) is a well-known extra-wide bandgap semiconductor and one of the promising materials used for power photoelectric devices, gas sensors, catalytic agents, etc. This work presents the suppression of self-trapped holes (STHs) and increase of oxygen vacancies (VO) in β-Ga2O3 microspindles by doping of Zn ions as well as the electrocatalytic activity of these microspindles. Undoped and Zn-doped β-Ga2O3 microspindles were prepared by a hydrothermal method followed by high-temperature calcination. Scanning electron microscopy (SEM) and X-ray diffraction (XRD) results show that the morphology and structure of the samples did not change after low dose of Zn doping. The analyses of temperature-dependent photoluminescence (PL) spectra and X-ray photoelectron spectroscopy (XPS) indicate that incorporation of divalent Zn ions as deep acceptors can increase VO concentration and effectively suppress the formation of STHs. Enhanced electrocatalytic activity was observed in Zn-doped β-Ga2O3 microspindles compared with undoped β-Ga2O3 microspindles. The new active sites introduced by Zn doping, higher VO concentration, and suppressed STHs are believed to be responsible for the enhanced electrocatalytic performance of Zn-doped β-Ga2O3 microspindles. This work is expected to expand the application of β-Ga2O3 based microstructures in electrocatalysis and provide innovative ideas for energy and environmental issues. [ABSTRACT FROM AUTHOR]

A large number of studies have been conducted to examine China's CO2 emissions problem disaggregated to the city level. However, few studies have delved further into the black box of economic production to examine the characteristics of CO2 emissions at the city supply chain level. In the context of the reality that Beijing takes the lead in achieving CO2 emissions reduction, this study decomposes CO2 emissions change in Beijing at three levels: overall, supply stage, and supply chain, using structural decomposition analysis (SDA) and structural path decomposition (SPD), filling the gap in urban CO2 emissions studies. The results show that: (i) energy consumption intensity is the most significant driver of emissions reduction, while per capita final demand is the largest factor in increasing emissions; (ii) Beijing's emissions reduction contribution is mainly reflected in the first supply stage (76.50%) and the second supply stage (18.85%); (iii) the expansion of domestic exports and thus greater demand for transportation is significant in emissions increase supply chains; (iv) the improvement of the demand structure for electricity from domestic exports contributes a large part in emissions reduction supply chains; (v) the existence of many offsetting effects, such as the ebb and flow of domestic exports on the demand for different products, has led to the loss of emissions reduction. Finally, corresponding policy recommendations are presented from the energy, industry, and demand perspectives. Our study will provide assistance in developing more microscopic policies to reduce emissions and replicating the Beijing experience. [ABSTRACT FROM AUTHOR]