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The ability to engineer a photoelectrode surface is pivotal for optimizing the properties of any photoelectrode used for solar fuel production. Altering crystal facets exposed on the surface of photoelectrodes has been a major strategy to modify their surface structure. However, there exist numerous ways to terminate the surface even for the same facet, which can considerably alter the photoelectrode properties. Here we report tightly integrated experimental and computational investigations of epitaxial BiVO4 photoelectrodes with vanadium- and bismuth-rich (010) facets. Our study demonstrates that even for the same facet the surface Bi:V ratio has a remarkable impact on the interfacial energetics and photoelectrochemical properties. We also elucidate the microscopic origins of how the surface composition can affect the photoelectrochemical properties. This study opens an unexplored path for understanding and engineering surface energetics via tuning the surface termination/composition of multinary oxide photoelectrodes. Surface facets are known to influence the behaviour of photoelectrodes for solar fuel production; however, the role of surface composition, which can vary even for the same facet, is less well understood. Here the authors find that the surface Bi:V ratio is a key factor that affects properties of BiVO4 photoanodes.

In situ synchrotron X-ray absorption near-edge structure characterization of thin-film titania growth by atomic layer deposition (ALD) over ZnO nanowires reveals persistent low-coordinated Ti motif...

As one of the most promising candidates of photoanode material, bismuth vanadate (BiVO4) has been paid wide attention and achieved remarkable progress. However, the full exploitation of solar-energ...

Bismuth vanadate (BiVO4) is a widely studied oxide in solar water splitting, known for its ease of synthesis, high charge extraction yields, and advantageous band alignment with water. We present a combined first-principles and experimental study of the electronic structure of the (010) surface of BiVO4 aimed at disentangling the impact of the surface and bulk oxygen vacancies on the electronic structure and transport properties. We found that oxygen vacancies are deep donors at the surface as they are in the bulk; our calculations on defect and polaron formation energies suggest that, while polarons formed from oxygen vacancies in the bulk can contribute to conductivity, those at the surface likely do not. Our results also show that out-of-plane structural relaxations at the surface contribute to the relatively immobile nature of electron polarons derived from surface oxygen vacancies. The structural model derived from first-principles calculation was validated by comparing computed results with experimental measurements of single-crystal and epitaxially grown single-crystalline BiVO4 samples. We also found a reasonably good agreement between our calculated and measured work functions for BiVO4 samples with and without oxygen vacancies.

Summary Effectively regulating heat flow between the human body and its environment not only increases thermal comfort but also presents a novel and potentially cost-effective approach to reducing building energy consumption. Infrared property-engineered textiles have been shown to passively regulate radiative heat dissipation for effective cooling and warming of the human body. However, a lack of dyes that can tune the textile color without compromising the infrared properties remains a major impediment to textile commercialization. Here, we report a new strategy utilizing inorganic nanoparticles as a coloring component for scalable brightly colored, infrared-transparent textiles. The as-fabricated composite textiles not only show a high infrared transparency of ∼80% and a passive cooling effect of ∼1.6°C–1.8°C but also exhibit intense visible colors with good stability against washing. This facile coloration approach will promote the commercialization of radiative cooling textiles in temperature-regulating wearable applications for effective energy savings.

This study investigated crashworthiness characteristics of a circular aluminum tube internally reinforced with a composite skeleton and aluminum foams subjected to quasi-static axial crushing load. For a comparative purpose, an empty tube and tubes with single reinforcement (aluminum foams or composite skeleton) were tested as well. The deformation patterns and several key parameters related to the crashworthiness of these structures were investigated and compared. The experimental results showed that the proposed design offered the best energy absorption characteristics, and the specific energy absorption increased by 32% compared to the empty tube. In order to explore the mechanisms of enhancement in energy absorption, the composite skeleton and the tube filled with separated foams were tested, and the strong interaction between foams and the skeleton has been found to have a very remarkable contribution to total energy absorption. Additionally, numerical models were built based on different material constitutive relationships and validated by experimental results. Further parametric studies were performed to investigate the effects of tube thickness, skeleton thickness and foam density on crashworthiness. It is found that tube thickness is more important to affecting crashworthiness, which provides a basis for structural optimization.

This paper presents a double loop controller for a 7-DoF automobile electrohydraulic active suspension via T-S fuzzy modelling technique. The outer loop controller employs a modified H-infinity feedback control based on a T-S fuzzy model to provide the actuation force needed to ensure better riding comfort and handling stability. The resulting optimizing problem is transformed into a linear matrix inequalities solution issue associated with stability analysis, suspension stroke limit, and force constraints. Integrating these via parallel distributed compensation method, the feedback gains are derived to render the suspension performance dependent on the perturbation size and improve the efficiency of active suspensions. Adaptive Robust Control (ARC) is then adopted in the inner loop design to deal with uncertain nonlinearities and improve tracking accuracy. The validity of improvements attained from this controller is demonstrated by comparing with conventional Backstepping control and a passive suspension on a 7-DoF simulation example. It is shown that the T-S fuzzy model based controller can achieve favourable suspension performance and energy conservation under both mild and malevolent road inputs.

The effectiveness of a reverse logistics strategy is contingent upon the successful execution of activities related to materials and product reuse. Green supply chain (GSC) in reverse logistics aims to minimize byproducts from ending up in landfills. This paper considers a retailer responsible for recycling and a manufacturer responsible for remanufacturing. Customer environmental awareness (CEA) is operationalized as customer word-of-mouth effect. We form three game theoretic models for two different scenarios with different pricing strategies, i.e. a non-cooperative pricing scenario based on Stackelberg equilibrium and Nash equilibrium, and a joint pricing scenario within a cooperative game model. The paper suggests that stakeholders are better off making their pricing and manufacturing decision in cooperation.

The smart metering infrastructure of comprehensive energy supply is the key to achieving high- quality energy measurement of "fairness, safety and efficiency" and creating a customer-centered enterprise customer community. Focusing on the realization of intelligent measurement targets in the energy Internet environment, this paper combs the innovative technologies from the four aspects of "measurement and terminals, communication network, acquisition master stations and business application" according to the characteristics of smart metering infrastructure, and forms total requirements through demand identification. On this basis, this paper gives implementation measures such as ‘lean measurement guarantee towards verification quality’, ‘communication network and safety protection’, ‘operation management for acquisition master stations towards massive data’, and ‘demand-oriented business application’ to meet the requirements ‘sufficiency, suitability and effectiveness’ of the future design of smart metering. Through the research on the smart metering infrastructure of comprehensive energy supply dominated by electricity, this paper promotes the future energy network to meet the measurement needs of multiple energy sources (electricity, gas, water, heat, etc.), and realizes the coordinated operation of multiple energy types and the interconnection of multiple energy sources in energy internet.

In China’s low-carbon development progress, industrial sectors play a crucial role in reducing CO2 emissions and maintaining economic growth targets. Because the Chinese government is promoting industrial structure transformation for “high-quality economic development,” the dominant CO2 emitters have changed in recent years. It is important to identify the trend evolution of industrial CO2 emitters and implement targeted measures and policies for CO2 emission control at the sector level. In this paper, a hybrid input–output model is adopted to assess the situation and trend of sectoral CO2 emissions from 2002 to 2017 in China. Demand-side drivers of sectorial embodied CO2 emissions are discussed. Based on the embodied CO2 emission decomposition of 27 sectors, a CO2 emission evaluation index is defined for CO2 emission ranking and key sectors for embodied CO2 emissions are identified. For the key CO2 emitters, we provide targeted policy suggestions for CO2 emission mitigation from the perspective of trend evolution and index ranking. The results indicate the following. (1) 2015 is a turning point for China’s CO2 emission mitigation progress, because the previously increasing embodied CO2 begins to decrease from 2015 to 2017. (2) Although the Construction sector stimulates a large amount of CO2 emissions at present, the major driving forces of CO2 emissions have gradually changed from infrastructure construction to the increasing demand of consumer goods, service industry, and export of technology-intensive products. (3) The CO2 emission intensity of the Electric Power and Heat Supply sector has increased, and promotion of renewable energy consumption is urgently needed. (4) From the demand-driven aspect, tertiary industry has greater CO2 emission potential than heavy industry.

Energy storage technology plays a significant role in the pursuit of the high-quality development of the electricity market. Many regions in China have issued policies and regulations of different intensities for promoting the popularization of the energy storage industry. Based on a variety of initial conditions of different regions, this paper explores the evolutionary process of electricity market players considering energy storage technology. The trilateral evolutionary game model is adopted to analyze the strategies of the power plant, the power grid, and the government. After assigning the model according to an actual situation, each equilibrium point corresponds to a real electricity market situation. The results indicate the following: (1) In the process of stabilizing, the role of “Advanced Imitators” leading the strategy of building energy storage changes between the power plant and the power grid. (2) In Eastern, Middle, and Southern China, the power plants and power grids on a greater-than-medium scale will choose to build energy storage without governmental regulations, due to the abundant net profit. (3) In the northeast of China, power plants with a medium-or-lower scale will choose not to build energy storage because of the relatively low on-grid price, and small power grids can make enough profits by operating energy storage facilities. (4) In Northern China, the large power plants and the medium power grids will choose to build energy storage due to the high electricity sale price and the resulting high profit. (5) In Western China, the small power plants and power grids cannot afford to build energy storage due to the low electricity price. The results lead to valuable policy suggestions for the local governments of China in promoting energy storage in the future. To meet the goal of energy storage popularization, regional electricity market plans need relevant policies based on its existing conditions, offering suitable external conditions for adding energy storage.

With the advent of Web 2.0 application, and the increasing number of browsers and platforms on which the applications can be executed, cross-browser incompatibilities (XBIs) are becoming a serious problem for organizations to develop web-based software. Although many techniques and tools have been proposed to detect cross-browser issues, there still lacks a comprehensive approach to locate the root causes of various cross-browser issues. To address this limitation, this paper proposes X-Diag, an automated technique for debugging XBIs based on our findings from an extensive study of the root causes of XBIs in real-world applications. The characteristic of X-Diag is that it narrows down the root causes of cross-browser issues step-by-step by checking whether such issues are caused by incompatible DOM APIs, CSS properties or Html elements. Our empirical evaluation shows that X-Diag is effective in locating the root causes of cross-browser issues, and can provide useful support to developers for (eventually) eliminate XBIs.

Space heating accounts for the largest energy end-use of buildings that imposes significant burden on the society. The energy wasted for heating the empty space of the entire building can be saved by passively heating the immediate environment around the human body. Here, we demonstrate a nanophotonic structure textile with tailored infrared (IR) property for passive personal heating using nanoporous metallized polyethylene. By constructing an IR-reflective layer on an IR-transparent layer with embedded nanopores, the nanoporous metallized polyethylene textile achieves a minimal IR emissivity (10.1%) on the outer surface that effectively suppresses heat radiation loss without sacrificing wearing comfort. This enables 7.1 °C decrease of the set-point compared to normal textile, greatly outperforming other radiative heating textiles by more than 3 °C. This large set-point expansion can save more than 35% of building heating energy in a cost-effective way, and ultimately contribute to the relief of global energy and climate issues., Energy wasted for heating the empty space of the entire building can be saved by passively heating the immediate environment around the human body. Here, the authors show a nanophotonic structure textile with tailored infrared property for passive personal heating using nanoporous metallized polyethylene.

Carbon fibre reinforced plastics (CFRP) are characterized by lightweight, high specific strength and stiffness, superior energy-absorbing capacity, and excellent design flexibility. Thus, use of CFRP thin-walled structure as crashworthy application can improve fuel economics and crashworthiness characteristics compared with their metal counterparts. In this study, we reported crushing behavior of several CFRP tapered tubes with various cross-sectional profiles and tapered angles under multiple load cases through numerical simulations. The influences of cross-sectional profiles, tapered angle and loading angle on crashworthiness of all configurations were explored by comparing their failure modes, load-displacement curves, crashworthiness indicators and energy-absorbing mechanisms. It was found that a positive correlation between total energy-absorbing capacity and the edge number of cross section profile was demonstrated, and the tapered tubes with circular profile showed the best total energy-absorbing capacity under both axial and oblique loadings. Besides, it was indicated that the energy-absorbing capacity of the tubes reduced in different degrees with increasing impact angle, and raising tapered angle of the tube was capable to mitigate this reduction degree. Further, the complex proportional assessment method (COPRAS) was adopted to effectively pick up the optimal configuration from all configurations concerned. It was found that H-6, which is the CFRP tapered tube with hexagonal profiles and tapered angle of 6°, was the best configuration, indicating its superiority in crashworthiness characteristics under multiple load cases. Finally, the CFRP tapered tube H-6 was further optimized by using a discrete optimization method to improve its crashworthiness characteristics, and the results showed that the SEA α was improved by 4.35% from the initial design. This study demonstrated that the proposed two-step process (firstly select the best optimal configuration based on COPRAS; then perform the discrete optimization) was fairly effective to obtain an optimal configuration for crashworthiness design of CFRP tapered tubes under multiple load cases.