Institutional Repository of GuangZhou Institute of Energy Conversion, CAS
Not a member yet
23976 research outputs found
Sort by
Engineering <i>in situ</i>: N-doped porous carbon-confined FeF<sub>3</sub> for efficient lithium storage
No full textMetal fluorides confined in heteroatom-doped carbon nanostructures are viewed as one of the most promising high capacity cathodes for high-performance lithium rechargeable batteries. Herein, we present a facile in situ reaction approach to synthesize nitrogen-doped porous carbon (NPC)-confined metal fluorides, which involves in situ etching toward a Schiff-base organic precursor and fluorination of metal oxides by polytetrafluoroethylene during a one-step heating process. The afforded NPC-confined FeF3 (FeF3@NPC) facilitates fast Li+/e- diffusion kinetics, accommodates severe volume fluctuation and reduces the FeF3 cathode dissolution, thus providing an outstanding high-rate capacity of 181 mA h g-1 at 5 C, accompanied by superior cycle life within 500 cycles at 2 C. This novel approach opens up new horizons to design high-performance nanoconfined metal fluoride-based materials for sustainable energy applications
Effect of Ionic Composition on Methane Hydrate Formation Kinetics in Natural and Artificial Deep-Sea Seawater
No full textOn the cold seep seafloor, methane hydrate is an important form of carbon storage. The stability of methane hydrates and mechanisms of ionic effects on hydrates are closely related to seafloor methane release and carbon cycling. Cold seeps are endowed with abundant and high-quality hydrate resources under the environmental conditions of low temperatures and high pressures. Methane hydrates are seen as a potential source of renewable energy and a possible form of energy storage, as the global demand for clean energy increases. Although studies have focused on the formation and dissociation processes of methane hydrates, the influence of seawater ions on the kinetics of hydrate formation is still unclear. In this study, we studied the formation kinetics of methane hydrate in ion systems, analyzed the effects of various main ions, and compared them with in situ seawater composition. The phase equilibrium point of methane hydrate in the in situ seawater system was experimentally determined by us to better understand the stability. The degree of inhibition on the methane hydrate formation kinetics in natural seawater is more closely to that of CaCl2, MgCl2, and SrCl2, as indicated by gas consumption during methane hydrate formation. However, NaCl exhibits a greater inhibition effect than that of CaCl2, MgCl2, and SrCl2. The thermodynamic behavior of in situ seawater is consistent with the inhibition degree of SrCl2 on methane hydrate formation. In addition, morphological characteristics of hydrates possessed dense powdery particles and ice particles on the surface of the seawater-methane system, which combined with both hydrate morphologies, the pure water-methane system (ice particles), and the saline ions-methane system (powdery particles). The findings of this study may provide a reference for further exploration of methane hydrate formation in cold seep environments and provide a basis for an in-depth understanding of submarine methane release and carbon cycling
Characterizations of high nitrogen-doped rice straw biogas residue biochars and their photocatalytic antifouling activity
No full textMarine fouling caused major economic losses and has been a global challenge on environment protection. Currently, photocatalytic played an important role in dealing with sea pollution, enhancing the ability of resisting the bacteria and algae effectively. Rice straw biogas residue biochar with the natural in-situ nitrogen functional group has been widely utilized in the field of photocatalytic. The nitrogen functional group could effectively improve the photogenerated carrier transport rate. In addition, Cu2O as a typical photocatalyst could boost the photocatalytic ability, improving the performance of photocatalytic antifouling. In this work, the rice straw biogas residue biochar and Cu2O composited material (BRC) was synthesized by hydrothermal treatment and utilized in the field of photocatalytic and pollution removal. The natural nitrogen-containing lignocellulosic biochar was carbonized from rice straw biogas residue after anaerobic digestion and hydrothermal treatments. The BRC could impede the electron-hole complexation and continuously and efficiently generate reactive oxygen species (ROS), possessing an efficient photo-utilization rate. The BRC could exhibit excellent photocatalytic antifouling performance, with an antimicrobial rate of more than 95 %, and Chlorella adhesion density reduced by 94 %. In addition, BRC not only realized the resourceful utilization of agricultural waste, but also had a good prospect for the practical application of marine antifouling
Thermodynamic and economic performance of super-long gravity heat pipe geothermal power plant
No full textHot dry rock energy has the potential to be a solution for both energy shortage and carbon -emission reduction. The novel technical scheme based on the super -long gravity heat pipe system in a single well has aroused great interest in the geothermal research and industry community; however, there is yet very few investigations on its power generation performance. Unlike other hot dry rock energy exploitation technologies, super -long gravity heat pipe produces saturated vapor, which can directly drive a steam turbine to generate electricity in a similar fashion to thermal power plants. This study comprehensively analyzes and compares the performance of the super -long gravity heat pipe system with the traditional single -well downhole heat exchanger system from the perspective of technology and economy. The acquired knowledge gives in-depth information about the superlong gravity heat pipe geothermal power generation system. The analysis and comparison are based on a novel thermodynamic and economic model specially developed in this study. Both systems consider the same geothermal conditions and the working fluid of both systems is optimized to maximize their power output. Thermodynamic results show that the super -long gravity heat pipe system has higher efficiency compared to that of the downhole heat exchanger system. The economic analysis indicates that the downhole heat exchanger system involves slightly lower costs than those of the super -long gravity heat pipe system, while the levelized cost of energy of downhole heat exchanger system is, much higher than that of the super -long gravity heat pipe system. For the baseline cases investigated, the energy efficiency of the super -long gravity heat pipe system is 10.92%, which is 1.37 times that of the downhole heat exchanger system; having a larger scale power station by increasing the number of wells from 1 to 10 makes the levelized cost of energy decrease from 0.30 /kWh for the super -long gravity heat pipe system, and from 0.74 /kWh for the downhole heat exchanger system
Access Repository Dashboard
Do you manage Institutional Repository of GuangZhou Institute of Energy Conversion, CAS? Access insider analytics, issue reports and manage access to outputs from your repository in the CORE Repository Dashboard!