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A hierarchical CoP@ZnIn2S4 photocatalyst was prepared via a MOF-templated strategy, which exhibited superior activity owing to the unique morphology.

The conversion of CO2 under mild condition is of great importance because these reactions involving CO2 can not only produce value-added chemicals from abundant and inexpensive CO2 feedstock but also close the carbon cycle. However, the chemical inertness of CO2 requires the development of high-performance catalysts. Herein, Ag nanoparticles/MIL-100(Fe) composites were synthesized by simple impregnation-reduction method and employed as catalysts for the photothermal carboxylation of terminal alkynes with CO2. MIL-100(Fe) could stabilize Ag nanoparticles and prevent them from aggregation during catalytic process. Taking the advantages of photothermal effects and catalytic activities of both Ag nanoparticles and MIL-100(Fe), various aromatic alkynes could be converted to corresponding carboxylic acid products (86%–92% yields) with 1 atm CO2 at room temperature under visible light irradiation when using Ag nanoparticles/MIL-100(Fe) as photothermal catalysts. The catalysts also showed good recyclability with almost no loss of catalytic activity for three consecutive runs. More importantly, the catalytic performance of Ag nanoparticles/MIL-100(Fe) under visible light irradiation at room temperature was comparable to that upon heating, showing that the light source could replace conventional heating method to drive the reaction. This work provided a promising strategy of utilizing solar energy for achieving efficient CO2 conversion to value-added chemicals under mild condition.

We investigated the relationship between perceived value of virtual goods and willingness to consume virtual goods in online mobile games, and examined the roles of gamers' intention to use virtual goods and extraversion in this relationship. We constructed a moderated mediation model to analyze data from 894 undergraduate students in China. Perceived value was positively correlated with willingness to consume, and intention to use played a mediating role in this relationship; further, the indirect effect of intention to use was moderated by extraversion, with a weaker effect occurring for lower extraversion. Thus, perceived value positively predicted intention to use, which increased willingness to consume, and extraversion enhanced the influence of perceived value on intention to use.

Photocatalytic hydrogen evolution by water splitting is highly important for the application of hydrogen energy and the replacement of fossil fuel by solar energy, which needs the development of efficient catalysts with long-term catalytic stability under light irradiation in aqueous solution. Herein, Zn0.5 Cd0.5 S solid solution was synthesized by a metal-organic framework-templated strategy and then loaded with MoS2 by a hydrothermal method to fabricate a MoS2 /Zn0.5 Cd0.5 S heterojunction for photocatalytic hydrogen evolution. The composition of MoS2 /Zn0.5 Cd0.5 S was fine-tuned to obtain the optimized 5 wt % MoS2 /Zn0.5 Cd0.5 S heterojunction, which showed a superior hydrogen evolution rate of 23.80 mmol h-1 g-1 and steady photocatalytic stability over 25 h. The photocatalytic performance is due to the appropriate composition and the formation of an intimate interface between MoS2 and Zn0.5 Cd0.5 S, which endows the photocatalyst with high light-harvesting ability and effective separation of photogenerated carriers.

Information asymmetry between online financial lenders and borrowers may lead to a high risk of overdue repayment. To identify the influencing factors of the default rate in Chinese online lending,...

Photocatalytic water splitting taking the advantage of using solar energy directly is one of the most effective strategies for hydrogen evolution. The development of facile methods for synthesizing highly efficient and stable photocatalysts for hydrogen production still remains a great challenge. Herein, a metal-organic framework (MOF)-templated strategy was designed for the synthesis of solid solutions of (Zn0.95Cu0.05)1-xCdxS that exhibit outstanding photocatalytic hydrogen production reaction activity. More importantly, efficient light capturing ability and photogenerated charges separation were accomplished via fine-tuning the composition of the photocatalysts by adjusting the concentrations of doping metals in the template MOFs. Under visible light (λ > 420 nm), an optimized nanocatalyst, (Zn0.95Cu0.05)0.6Cd0.4S, exhibited a higher durability and satisfied photocatalytic hydrogen evolution rate of 4150.1 μmol g-1 h-1 of water splitting.

Based on various well-defined components and structures, high specific surface areas and adjustable pore sizes, metal–organic frameworks (MOFs) have not only been widely used for gas sorption and separation as well as catalytic and sensing materials but have also been applied as the precursors for nanomaterials with promising applications such as in energy storage and conversion. In this review, we reported a summary of the recent progress of MOF-derived heterojunctions as nanocatalysts for photocatalytic hydrogen production from water splitting, which is organized in two main categories: (i) using the pore chemistry of MOFs to accommodate small species for MOF-derived heterojunctions; (ii) using the surface chemistry of MOFs to combine with other functional species for MOF-derived heterojunctions. The fundamentals of the rational design and synthesis of MOF-derived heterojunctions for photocatalytic hydrogen production were discussed in detail.

The green and healthy development of the energy system is related to the sustainable development of economic activities. The quantitative sustainable evaluation of the energy system is the guiding principle of the current energy structure transformation. Therefore, this paper adopts the emergy analysis theory, based on the development forecast of the power supply structure in different stages of China, firstly, the environmental loading ratio, emergy yield ratio, emergy sustainability index and emergy investment ratio are used to carry out the five common power generation modes, including wind power, photovoltaic power, coal power, gas power and hydropower, and it is concluded that under the current conditions, the emergy sustainability index of wind energy is optimal. Thirdly, considering the four dimensions of power generation efficiency, installed cost, full life cycle cost, and emergy sustainability index, a comprehensive evaluation system of China’s electric energy system based on emergy analysis is proposed, which quantifies the development trend of the structure has shifted from coal-based to diversified with clean energy and scenery from 2020 to 2050. The comprehensive evaluation result has increased from 0.2 to 1. The comprehensive evaluation results continue to increase with the year, indicating that China’s electric energy structure is more optimized, showing a higher vigor of sustainable development.

Considering the huge power consumption, rapid response and the short-term heat reserving capacity of the air conditioning load in the building&rsquo, s energy system, the air conditioning load and its system can be equivalent to the virtual energy storage device for the power grid. Therefore, to obtain a high matching building renewable energy system, a virtual energy storage system of the air conditioning load, accompanied by a storage battery, was built in the paper. Then, operating strategies for the virtual energy storage of the air conditioning load and storage battery were designed. Further, to quantize the contribution of the virtual energy storage to the improvement of matching characteristics, two indicators of the demand side and supply side in the energy system were adopted, including on-site energy fraction (OEFr) and on-site energy matching (OEMr). Lastly, matching characteristic research of the building&rsquo, s renewable energy system based on virtual energy storage of the air conditioning load was established and analyzed by TRNSYS and MATLAB in Tianjin, China. The results revealed that a better matching characteristic performance of the building&rsquo, s renewable energy systems driven by virtual energy storage was obtained. In the condition set out in the paper, compared with that without virtual energy storage, the average values of OEFr and OEMr after virtual energy storage were 0.66 and 0.77, which increased by 8.19% and 8.45% respectively. Simultaneously, the battery operation performance in the building renewable system was improved when the virtual energy storage was working. The times of charge and discharge cycles decreased after virtual energy storage, and the depth of discharge of the battery reduced by 23.37% on a specific day.

Photocatalytic hydrogen evolution by water splitting is highly important for the application of hydrogen energy and the replacement of fossil fuel by solar energy, which needs the development of efficient catalysts with long-term catalytic stability under light irradiation in aqueous solution. Herein, Zn

Photocatalytic water splitting taking the advantage of using solar energy directly is one of the most effective strategies for hydrogen evolution. The development of facile methods for synthesizing highly efficient and stable photocatalysts for hydrogen production still remains a great challenge. Herein, a metal-organic framework (MOF)-templated strategy was designed for the synthesis of solid solutions of (Zn

Geothermal power generation (GPG) is a technology that need to be promptly developed due to the high capacity factor and the low environmental impacts. In the year of 2020, as the pivotal juncture of China's 13th Five-Year Plan, it is necessary to summarize the GPG history of China in the past 60 years and comprehend its technological status to secure a promising future of the GPG in China. In this regard, this paper aims to reveal the challenges, opportunities and outlooks of GPG technologies in China from the perspective of the above-ground strategies. The possibility of realizing the planned GPG goal in 2020 in China was firstly discussed. In addition, a technical analysis was done to obtain the main technical obstacles, including the poor energy endowment of the geothermal resources and the immature technology of GPG systems. It is evident that the poor matching between the geothermal fluid and the adopted thermal power cycle hinders the development of GPG, especially for the technologies using the organic Rankine cycle(ORC). Nevertheless, there are many opportunities for improving the level of GPG in China, which may be based on transforming abandoned oil wells into geothermal wells, exploiting dry hot rocks, or developing multi-energy complementary systems. Except for the above, by interpreting the experimental research and the energic, economic and environmental optimization of ORC-GPG systems worldwide, crucial recommendations are provided for the promotion of the GPG technologies in China. These include the performance decoupling based on thermodynamic process, multi-objective optimization based on Pareto's non-inferior solution, comprehensive utilization based on cascading principle, environmental impact assessment based on life cycle assessment, as well as experimental studies on Flash-ORC.

As a greenhouse gas, the increasing concentration of CO2 in atmosphere has resulted in a series of environmental problems. However, being the cheapest and most abundant nontoxic C1 source, CO2 has been taken as a promising feedstock for industrial production of high value-added products. Among many different strategies for CO2 conversion, electrocatalytic reduction of CO2 is regarded as one of the cleanest and most efficient approaches. During CO2 electroreduction reaction (CO2ERR), various products could be formed by different catalysts at different potentials, on which the coordination between CO2, CO or other reduction intermediates and the catalyst takes great effect. Herein, this review summarizes the reaction mechanism of CO2ERR based on the principles of coordination chemistry, as well as the diverse properties of the electrocatalysts reported to date in detail, with the purpose of benefiting future research to rationally design electrocatalyst with high selectivity and activity. Furthermore, we offer some prospects and challenges on the future outlook for CO2ERR.

Trisubstituted piperazinones, piperazines, tetrahydropyrazines, and dihydropyrazinones were prepared in a one-step procedure from easily accessible polymer-supported acyclic precursors containing either a masked aldehyde or ketone group. Acid-mediated unmasking of the aldehyde triggered cyclic iminium formation followed by reduction with triethylsilane present in the cleavage cocktail. The effect of the substituent at the iminium-forming nitrogen was evaluated: whereas complete conversion to the target compounds was observed with N-alkyl, aryl, and phenylsulfonamido derivatives, the N-acyl compound suffered from a partial reduction of the aldehyde to an alcohol. Similarly, ketones readily provided cyclic iminiums with N-alkyl compounds, whereas their cyclization with N-acyl precursors proceeded unwillingly. Interestingly, cleavage of the resin-bound acyclic precursor at 60 °C in the presence of triethylsilane resulted in the decomposition of the amide bond and formation of a lactone. An analogous synthetic route was also successfully used for the preparation of piperazines and tested as an alternative route for the synthesis of diazepanones.