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Developing efficient catalysts to produce clean fuel by using solar energy has long been the goal to mitigate the issue of traditional fossil fuel scarcity. In this work, we design a heterostructure photocatalyst by employing two green components, Ni(OH)2 and ZnIn2S4, for efficient photocatalytic H2 evolution under the illumination of visible light. After optimization, the obtained photocatalyst exhibits an H2 evolution rate at 0.52 mL h−1 (5 mg) (i.e., 4640 μmol h−1 g−1) under visible light illumination. Further investigations reveal that such superior activity is originated from the efficient charge separation due to the two-dimensional (2D) structure of ZnIn2S4 and existing high-quality heterojunction. [ABSTRACT FROM AUTHOR]

Hydrogenation reactions are an important process in today's chemical industry. Typically, hydrogenation reactions involve the removal of an unsaturated bond in olefins or other polyenes via thermal catalysis using hydrogen. As hydrogenation reactions are often carried out at temperatures up to several hundred degrees, they require significant energy input which typically comes from burning fossil fuels. In order to conserve fossil fuels and reduce CO2 emissions, researchers are now developing photothermal catalysts for hydrogenation reactions, which harness concentrated sunlight to achieve the required reaction temperatures or introduce sunlight into thermal-driven reaction systems to reduce the reaction temperatures. Photothermal catalysts thus need to be able to efficiently absorb sunlight, whilst also being able to drive the desired hydrogenation reaction with high activity and selectivity. In this review, we summarize recent research aimed at the development of photothermal catalysts for CO2/CO hydrogenation and alkene/alkyne/aromatic hydrogenation. Particular emphasis is placed on uncovering the reaction mechanisms at the molecular level, which in turn guides the rational design of photothermal catalysts with better performance. [ABSTRACT FROM AUTHOR]

Hydrogen, an ideal carbon-free energy carrier with favorable combustion properties, has drawn worldwide attention as a high-expectation way to enhance fossil fuels' combustion performance. However, currently, limited investigations are about enhancing n-butanol hybrid gasoline engines through hydrogen addition. Thus, in this paper, the hydrogen direct injection (HDI) was put forward to improve an SI engine fueled with n-butanol/gasoline, and the synergic effect of hydrogen and n-butanol on combustion and emission characteristics was studied. Experimental results indicated the favorable influence of a low n-butanol mixing ratio (ν N , ν N = 25%) on enhancing combustion can relatively weaken the similar promoting effect of hydrogen. And the sequential increase in hydrogen addition ratio (φ H , φ H = 15–20%) can compensate for the negative impact of unfavorable atomization and vaporization quality caused by higher n-butanol blending (ν N = 75–100%), namely the usage amount of n-butanol in engine can be raised. Further, compared with pure gasoline, the percentage change in BMEP (brake mean effective pressure) at ν N = 25% and 100% can be increased from 1.79% to 5.04% and −5.38%–2.01% respectively by φ H from 0 to 20%. Besides, the HDI can also shorten the combustion duration, accelerate the heat release process and improve the combustion stability of each ν N , while the amplitude of promotion exhibits a relative downtrend with the increase of φ H. As for emission characteristics, the HC, CO and particulate emissions decreased monotonously with the increasing φ H under all ν N , but there was a visible increase in NO X emissions. • A hydrogen direct injection SI engine fueled with n-butanol/gasoline is proposed. • The engine performance with five hydrogen/n-butanol ratios is investigated. • A small n-butanol has a similar enhanced influence on combustion as hydrogen. • The usage of high n-butanol hybrid fuel can be achieved by increasing hydrogen. [ABSTRACT FROM AUTHOR]

[Display omitted] • Metal-acid bifunctional B-doped radial channel silica supported Ni 2 P catalyst was prepared. • Open radial channels of RCSN promote fast mass transfer and shorten reaction time. • Open radial channels of RCSN are conducive to efficient utilization of active sites. • B doping contributes to the improved acidity by forming the trigonally and tetrahedrally coordinated B in RCSN skeleton. • Ni 2 P/RCSN-B shows high HDO activity (96.5 %) and target deoxidation products yield (91.5 %) within 1 h. Upgrading bio–oil into high–quality hydrocarbon fuel through hydrodeoxygenation (HDO) is highly desirable. Here we describe a method for fabricating a Ni 2 P metal–acid bifunctional catalyst (Ni 2 P/RCSN–B) supported on B–doped radial channels silica by a facile anion–assisted hydrothermal method. The results showed that the doped B was entered into the skeleton of RCSN to form the trigonally and tetrahedrally coordinated B species, providing the adjustable acid sites, which is responsible for the high target methylcyclohexane (MCH) product selectivity. And the radial channel pore structure promotes the efficient exposure of active sites, accelerates the mass transfer and leads to highly dispersed small Ni 2 P particles. Importantly, the kinetics study proved a high reaction constant for the constructed Ni 2 P/RCSN–B catalyst as compared to that of Ni 2 P supported on traditional SiO 2 support, indicating the important role of the radial channel pore structure on shortening the reaction time. Benefit from the optimized acidity, rapid mass transfer and highly dispersed small Ni 2 P particles, Ni 2 P/RCSN–B achieved superior m–cresol HDO performance with HDO activity reaching 96.5 % and the selectivity to MCH reaching 91.5 % within 1 h. There is no doubt that the combination of Ni 2 P and RCSN–B opens up a new idea for preparing high performance HDO catalysts. [ABSTRACT FROM AUTHOR]

• In recent years, China has prioritized ecological security (ES) • An improved ecological footprint model can effectively assess ecological security. • Poor ES is found in eastern coastal areas and the second-third step boundary. • China should consider ES, energy security, and food security in future development. With the outbreak of the current global eco-environmental crisis, ensuring global and local ecological security (ES) has become a priority for many countries in the world. In the past few decades, social and economic development in China has induced many ecological and environmental problems, which have negatively impacted ES of China and the world. In recent years, with the increasing awareness of China's ecological and environmental protection, the Chinese government has actively participated in global ecological and environmental governance and raised ES to the height of national security. A systematic and comprehensive assessment of ES is the basis of ES assurance, which can enable governments to accurately grasp the ES status of different regions and adopt targeted management measures. The ecological footprint (EF) model is a mature model that has been widely used for ES assessment. Thus, this study used an EF model with localized parameters analyzing the spatiotemporal changes in China's ES from 2006 to 2016 on a provincial scale. Then, from an "occupation-carrying" perspective, this study explored the main aspect that induced changes in regional ES and identified the main type of ecological land that threatened regional ES. Results showed that a) during the study period, China's ES status showed a deteriorating trend and the current ES is not optimistic. However, the ecological carrying capacity of most provinces in China has increased, indicating that China's ecological and environmental protection has achieved initial results; b) currently, the provinces whose ES status are moderate unsafe and quite unsafe are mainly distributed in the eastern coastal region and the region near the boundary between the second and third ladders; c) the high-intensity occupation of the ecological environment and biological resources attributed to the rapid development of the social economy is the main cause for the negative changes in ES in most areas; d) for most provinces in China, cropland occupation and fossil energy consumption pose great threats to the regional ES status. China should jointly consider ES, energy security, and food security in its future development plans. [ABSTRACT FROM AUTHOR]

Solar driven catalysis by semiconductors is considered as a promising route to mitigate environmental problems caused by the combustion of fossil fuels and water pollution. Surface plasmon resonance (SPR) has offered a new opportunity to overcome the limited efficiency of photocatalysts. Herein we report that the SPR-mediated visible-light-responsive photocatalyst, 0.5 wt.% Au/SO 4 2− –TiO 2 , can achieve over 99% conversion of pollutants (thiophene, thiol, rhodamine B, and phenol) during photocatalytic oxidation with oxygen or air as oxidant under visible light irradiation. The considerable enhancement of photocatalytic activity can be attributed to the synergistic effect of Au SPR and Lewis acidic SO 4 2− –TiO 2 which are beneficial for the efficient separation and transfer of the photo-generated electrons and holes. Such a strategy would be important to the design and preparation of highly photocatalytic active semiconductor catalysts. [ABSTRACT FROM AUTHOR]