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Water, electricity, and ammonia (artificial fertilizer) are essential for human welfare. The self-sufficient and sustainable productions of them from renewable resources are indispensable for social security and the future society. In this study, we proposed the Water-Electricity-Ammonia (WEA) scheme that produces electricity, freshwater, and ammonia and supplies them at a certain ratio. We investigated the life cycle CO2 (LCCO2) emission from the case of inland cities in arid/semi-arid regions that obtain the three products (electricity, water, and ammonia) generated by photovoltaic (PV) and seawater obtained through a pipeline connecting the ocean and the cities. This study unraveled the necessary condition to reduce LCCO2 emission: the allocation ratio of PV electricity for the three productions and the geographical conditions of inland cities. To reduce LCCO2 emission, allocating PV power to seawater desalination is suitable if the city is in a lowland area, and ammonia synthesis is preferable if the city is in a highland area. Note that the WEA scheme applied to most inland cities, even in extreme geographical conditions, reduces LCCO2 emissions compared to conventional production methods by optimizing the PV allocation of electricity, freshwater, and ammonia production.

Durability performances are compared for Al-doped ZnO (AZO) transparent electrodes deposited on hard slide-glass and flexible polyimide-tape attached to polycarbonate (PI-tape/PC) substrates. To identify the appropriate sputtering configuration, the AZO thin films are first deposited on the glass substrates via reactive RF-magnetron sputtering under 90 sccm of argon gas and 3 sccm of oxygen gas at room temperature (RT) with 83 to 90 W of RF power for 30 min. When deposited, only the sputtering configuration with 85 W of RF power could produce the AZO films with acceptable optoelectrical properties for transparent electrodes: 80% average visual transparency and 10 Ω/□ at the thickness of 1.1 μm. The temperature at the surface of the substrates rises from RT to 88 °C due to the sputtering with 85W of RF power for 30 min, and this configuration is successfully conducted for AZO film depositions on both the glass and PI-tape/PC substrates. After exposure to a damp-heat (DH) test at 85 °C and 85% relative humidity (RH) for 25 days, the conductivity of the AZO films on the PI-tape/PC substrates is significantly degraded: many cracks are visible on the films, significantly decreasing the Hall mobility. Conversely, the films deposited on the glass substrates exhibit durable high conductivity, no cracks, and excellent stability of the Hall mobility. Despite this significant difference in Hall mobility evolution, the films on both substrates show similar patterns of a slight decrease in carrier concentrations, suggesting that chemical characteristics, extensively reported as the key for the DH degradation of AZO films, are less involved in this durability study featuring AZO films prepared via a low oxygen-to-argon gas ratio of reactive sputtering at low temperatures.

Novel amorphous iron hydrides (AIHs) are synthesized for the first time under ambient conditions by employing novel “quiescent reaction”, without stirring for mixing solutions, during a conventional aqueous reduction-precipitation process. The kind and morphology of AIHs are dependent on the processing condition, where two types are found, with one form consisting of a tangle of uniform nanowires and the other being granular in nature. Both AIHs undergo transformation to crystalline α-Fe by heat treatment at 600 °C. The nanowire AIH exhibits the hydrogen content of 0.10 wt%, while the granular AIH of 0.22 wt%. Their magnetic and thermal properties are accordingly different, and the non-diffusive hydrogen contributes to stability of AIHs. It is strongly suggested that, by use of quiescent reaction, iron-hydrogen clusters are formed and preserved at an early stage of precipitation reaction, and subsequently aggregated into novel AIHs, preventing α-Fe crystallization. Hence, the AIHs would be categorized as metastable hydrides stabilized with iron-hydrogen clusters. In addition, newly discovered quiescent reaction in aqueous solution, from which unprecedented AIHs are derived, sheds new light on fundamental and essential aqueous reaction.

Curtailment of variable renewable energy increases the Levelized Cost of Energy (LCOE), which is the tool often used to compare its profitability against traditional energy sources. Recently, the Kyushu Region of Japan had to curtail some of its solar production to meet energy balance. As many countries increase their solar energy production, curtailment will be inevitable. It is therefore important to develop methodologies to calculate it. In the case of Japan, curtailment can easily be estimated using hourly data. However, such data is unavailable in other countries. In this study, a methodology to reproduce curtailment using known periodicity and statistical data is presented. Insights were initially generated by simulating future curtailment scenarios of Kyushu to extract the factors that affect curtailment. Fourier analysis was used to identify the periodicity of demand and solar production. The Fourier representation was simplified using the identified factors. Along with statistical data, the demand and solar data were approximated and the curtailment was reproduced. Results show that curtailment can be closely reproduced using the proposed methodology on a yearly and monthly level. Further research is necessary to test the methodology for other conditions like having different climate, varying daily fluctuations, and other human-related fluctuations., The 6th International Conference on Power and Energy Systems Engineering (CPESE 2019), 20–23​ September 2019, Okinawa, Japan.

Contribution of renewable energy (RE) in current Malaysian energy mix is limited despite of the abundant biomass from its agriculture and sufficient sunshine and rainfall throughout the year. As future leaders, the acceptance of young generation towards RE reflects the most important public decision and policy especially in reducing dependency on fossil fuels. In order to optimise the successful of an awareness program, a set of questionnaire has been used to examine the perception and interpretation of university students towards RE. A total of 2,863 completed questionnaire were analysed according to educational background (science and non-science) and family economic status classified as Bottom 40 (B40), Middle 40 (M40) and Top 20 (T20). The results revealed that most of them have positive perception and optimistic on the usage of RE. Unfortunately, more focus and attention should be given to students with non-science educational background and those who came from Bottom 40 economic group in understanding renewable energy. There is also a gap on interpretation that indicates the need for more intellectual activities that covers information on development, technologies and benefit of RE.

Climate change mitigation is one of the biggest problems of the 21st century with anthropogenic carbon dioxide emissions having exceeded the carrying capacity for the planet. The primary contributor to the emissions is increasing nonrenewable energy consumption coupled with economic growth. A major area of social sciences is the study of decoupling energy-related emissions and energy usage from continuous economic growth. The goal of this review paper is to analyze various studies that have focused on decoupling energy and economy, regionally, nationally, and globally. The reviewed 93 investigations show that three kinds of methodologies are employed for decoupling analysis—structural decomposition, index decomposition, and statistical methods. The main factors that inhibit decoupling were found to be economic growth, fossil fuel consumption, and urbanization of population, while the factors that promoted decoupling were found to be energy intensity reduction and emission intensity reduction. A comparative analysis of the two promoting factors for decoupling revealed that emission intensity reduction is easier to implement than energy intensity reduction, because emission intensity does not depend on the fluctuations of economic growth. It is proposed that emission intensity reduction research needs to be accelerated for accurate policy decisions.

Community renewable energy (CRE) has recently been proposed as one of the effective policy tools to make a community sustainable and to strengthen this association. CRE is, however, not widespread yet in Thailand, and evidence-based research on CRE in the country is rather scarce. This paper aims to investigate the characteristics of CRE in Thailand to identify the key factors affecting its implementation. Data were collected through semi-structured interviews and document analysis for 26 active CRE projects in Thailand. Results show that the characteristics of CRE in Thailand are rooted in the geographical location of a community. A legal structure was created from a pre-existing group to implement a CRE project. The primary motivation for implementing CRE is sustainable development of a community. We examined essential factors separated into two groups—internal and external factors—in reference to CRE in developed nations. We highlight several issues concerning the further development of CRE in Thailand. First, a strong group leader and a formal structure are essential to drive and manage a project. Second, networks of CRE projects and long-term revolving funds are crucial external support to implement CRE.

Aluminum-doped zinc oxide (AZO) is one of the most promising transparent conductive oxide materials for a front electrode in solar cells. In this work, we roughened substrate surface and sputtered AZO films, where the effect of roughness on various AZO properties was investigated. The haze values were largely enhanced, retaining other important properties such as conductivity and transparency. The optical band gap exhibits a clear blue shift because of the roughness. The possible cause of this shift may be variation in the Al content due to the different deposition and post-annealing mechanisms of AZO films on the roughened surface.

An optimum treatment system for the waste electronic home appliance in remote area by local pre-processing and outsourcing post-processing is proposed. The cost reduction potential of the proposed treatment system is presented for main four types of electronic home appliances by the case study of Kinmen, Taiwan. Implementation of local pre-processing in Kinmen, Taiwan can provide 42, 54, 32, and 41 TWD unit cost reduction for television, washing machine, refrigerator, and air conditioner, respectively, comparing to the current treatment system. The different treatment characteristics according to the type of the appliances are the major factors for the applicability and cost reduction potential of the local pre-processing system. The application of this system to other cases is presented by sensitivity analysis with relative labor cost and transportation distance as the parameters. The results and the analysis process can be applied to the domestic systems with regions without recycling facilities, and also the international systems under the extended producer responsibility concept to take back the products for recycling.

The Japanese government decided to implement environmental remediation after the Fukushima Daiichi Nuclear Power Plant (termed “1F” in Japan) accident on 11th March 2011. As the initial additional annual dose target was set to be 1 mSv or less as a long-term goal, we examined the decision-making process undertaken by the then leaders, particularly the Minister of the Ministry of the Environment (MOE) who was responsible for the final decision. We found that technically based assessment of dose targets, health effects and risk-based approaches justified by scientific experts were not communicated to the then Minister and officials of the MOE before the remediation strategy was decided. We defined how such a decision was made based on leadership theories such as the Role Theory and the Cognitive Resources Theory. Academic leaders could have examined the Windscale accident (UK, 1957), which could be considered as the closest analogue (at least in terms of radionuclide releases) to the 1F accident. Environmental remediation could have been planned and implemented more effectively whilst still maintaining the highest possible safety standards and balancing the environmental and economic burden. Appropriate scientific input should have been provided by academic leaders to political and administrative leaders and such scientific justification should have been disclosed to the general public (especially the residents of Fukushima Prefecture) so that the general public could have developed greater trust in their leaders and have more readily accepted the decisions made., Environmental remediation; Nuclear power; Nuclear accidents; Waste management; Decision-making; Leadership

Ruthenium is an excellent catalyst for ammonia synthesis and recently shows quite high activity when supported on materials with high electron-donating and hydrogen-absorbing properties. The high activity is generally considered to originate from the two effects: the electron-donating property of the support, which reduces its apparent activation energy (appEa) to half of pure Ru’s appEa, and the hydrogen-absorbing property, which increases the active site by suppressing hydrogen poisoning, a drawback of ruthenium catalysts. Here, we investigated the catalytic performance of ruthenium loaded on TiMn2, a hydrogen storage material without electron-donating property to ruthenium. Ruthenium on TiMn2 showed the appEa reduced by half despite the lack of electron-donating property. It is plausible that the decreased appEa is due to the elimination of hydrogen over Ru by TiMn2. The hydrogen storage capacity is also an essential factor in discussing the appEa.

The Nuclear Waste Management Organization of Japan (NUMO) was established in 2000 as the organization responsible for the deep geological disposal of specified radioactive waste. Their siting process was initiated through open solicitation of volunteer host communities. However, no communities came forward with the exception of Toyo Town, which applied for the initial literature survey, but then withdrew the application due to strong opposition in 2007. To identify why the then mayor of Toyo Town failed, we analyzed his behavior and leadership characteristics, including how he collaborated with NUMO and the Agency for Natural Resources and Energy (ANRE). We identified the pattern of Machiavellian leadership, which was most likely the reason why he lost credibility and public trust. To improve the future siting process, we identified suitable leadership for high-level radioactive waste (HLW) management based on leadership theories. We determined that servant leadership is suitable because of its focus on the followers, with the achievement of organizational objectives being a subordinate outcome. With servant leadership characteristics, the leaders of NUMO, ANRE, and candidate municipalities may win trust because they value the people of the host communities and empower them to engage in decision-making during the siting process, which can help raise public acceptance.

Aluminum doped ZnO (AZO) thin films were deposited on glass substrates by using RF magnetron sputtering annealed under hydrogen atmosphere. The investigations were measured as functions of RF power, which varied in the range from 25 to 140 W. The lowest sheet resistance of 20 ohm/sq was obtained at sputtering power of 140 W. In X-ray diffraction analysis, all films have hexagonal wurtzite crystal structure with different preferable orientation. (110) peak appeared and the intensity increased with increasing RF power. The better environmental stability was found in AZO film prepared using high RF power. The most stable film was obtained when the film was annealed at high temperature in vacuum atmosphere. Investigation of the micro-effects of re-sputtering due to negative ion bombardment of growing thin films was also observed by FESEM. All property of the AZO thin film makes it suitable for transparent conductive electrode applications.

Agrivoltaic systems are multi-output systems where both solar power and crops are produced on the same land. Unlike other land-based photovoltaics (PV), the agrivoltaic PV modules are ground mounted between crops at some height with a certain tilt. Alternatively, PV modules replace part of a greenhouse or are partially set either below or above a covering material. The system could become an important mitigation option for climate change. However, power generation by PV reduces sunlight transmittance and therefore reduces agricultural yield. An allocation method that will address the potential interference of PV with crops is required for life cycle assessment (LCA) to evaluate greenhouse gas mitigation. This study aims to develop a new allocation method (i.e., solar allocation) and compare the LCA results of the new and traditional allocation methods (i.e., system expansion and economic allocation). The partition rate of the solar allocation is derived from the ratio of the active area covered by PV to the greenhouse surface area and light transmittance. These methods were applied to an agrivoltaic tomato production system using protected horticulture with the introduction of organic photovoltaics as a case-study of a system in Japan. The allocation methods considered in the present study could serve as potential methods in assessing life cycle−CO2 emissions. Above all, the solar allocation method can be used for many crops that will be influenced by PVs. Further improvement of the allocation method is required in cases where crop growth is less influenced by PVs (e.g., shadow-tolerant crops or transparent PV).

Energy literacy is a minimum required capacity for developing a sustainable society that participates in and discusses on energy and environmental (EE) issues. Understanding the energy literacy structure is of significant importance for providing effective energy education to promote people’s awareness of EE issues. In this article, an energy literacy structural model integrated with the Theory of Planned Behavior and Value-Belief-Norm Theory was investigated for 1070 lower secondary students (ages 13-15) in Japan. Structural equation modeling uncovered that the awareness of consequences is the most powerful predictor for the causality between basic energy knowledge and energy-saving behavior through the attitude toward the energy-saving behavior. A conditional process analysis elucidated that (1) the conditional effect of basic energy knowledge on the awareness of consequences depends on scientific literacy, critical thinking ability, and environmental worldview, and (2) the conditional direct and indirect effects in the mediation model of awareness of consequences on the attitude toward energy-saving behavior through the ascription of responsibility depend on environmental worldview or values and family discussion of energy-related issues. The energy literacy model proposed provides a theoretical contribution to the development of an effective energy education program.

Waste management is more challenging in small islands due to islands’ special characteristics. For small islands where energy recovery by incineration is difficult due to smaller waste generation amount with large seasonal fluctuations, waste shipments outside of island can make energy recovery possible. This study evaluated the cost effectiveness and environmental performance of waste shipments for energy recovery in case of small islands. The results shown that the direct shipment for incineration is expensive, but the emission prevention by energy recovery can surpass the emission from waste transportation. Waste shipments in the form of refused derived fuel (RDF) can reduce the transportation and incineration cost, but the high fossil fuel consumption in RDF production process resulted in high greenhouse gas emissions. The shipping distance, RDF gate fee, and emission from RDF production process have high influence on the cost effectiveness and environmental performance of the waste treatment process. The results of this study revealed the cost effective and environmental beneficial choosing criteria of waste shipments’ destination.

Although Li-BNICs (lithium boron nitride intercalation compounds) have been successfully synthesized by heat treatment, their crystal structures are still not clearly understood and controversial. In this study, several hypothetic phases of Li-BNICs are postulated and their phase stabilities are calculated through applying DFT (density functional theory), a common tool in first principles calculations. According to the experimental results on Li-BNICs, disordered structures have been suggested, which is also analyzed by introducing VCA (virtual crystal approximation) method for a disorder calculation. Lattice parameters, formation energies and electronic band structures for hypothetic Li-BNICs are estimated, where the VCA disorder calculation agrees well with experimental results, exhibiting negative formation energies. Li(BN)9 and Li(BN)3 are suggested as possible phases for Li-BNICs.

Optical and fluorescence properties of samarium (Sm) doped zinc aluminate host matrix (Sm:ZnAl2O4) was studied. Sm:ZnAl2O4 nanopowder was synthesized by vibrational milling process assisted with calcination treatment. Structural and optical properties of Sm:ZnAl2O4 nanopowders were investigated via the crucial parameter of different doping concentration. Structural properties of as-synthesized samples and Sm: ZnAl2O4 powders were characterized by X-ray diffraction and scanning electron microscope. For optical properties, Sm: ZnAl2O4 phosphor materials were analyzed via diffuse reflectance and photoluminescence spectroscopy. The preliminary results suggested that Sm: ZnAl2O4 powders were identically in spinel crystalline phase as host ZnAl2O4 structure affirmed by XRD result. SEM images indicated the Sm:ZnAl2O4 after the synthesis distinctly obtained in ultrafine power due to the effect of several milling round and sintering process. The optical properties in reflectance mode of Sm:ZnAl2O4 samples were significantly increased by the presence of Sm dopant in ZnAl2O4 structure. Meanwhile, the luminescent materials showed red emissions under visible light excitation in range of 650-730 nm by PL spectra. The improvement of ZnAl2O4 photoluminescence property was obviously obtained at 0.5 wt.% Sm due to photon transfer from Sm to host material.

Community Renewable Energy (CRE) projects is being promoted in many countries as well as in Thailand. This research investigated the benefits of CRE projects that were promoted by the Ministry of Energy of Thailand. Data from 26 CRE projects has been analyzed. It was found that there are 6 types of renewable energy that are used in the CRE projects. The most popular types of renewable energy are Biogas (12 projects) and Solar thermal (7 projects). Most of the projects are located in Northern and Southern of Thailand, 11 and 9 projects respectively. It is expected that the 26 CRE projects can produce 845 kW of thermal energy and 86 kW of electricity Direct benefits of CRE project. The project size ranges from 0.1 –5.1 Million THB (3,000-160,000 USD), in average 1.3 Million THB (40,000 UDS) per project. Total project value of all 26 projects were 34.5 Million THB (1,078,000 USD). The total co-investment from the Ministry of Energy were 20.3 Million THB (634,000 USD) or approximately 60% of the total project value. There are 1,638 households involved in the CRE projects. The CRE projects could either generate income or save expense worth approximately 5,530,000 THB (173,000 USD) per year. Several CRE projects can contribute to environment protection as well.

The monoclinic BiVO4 was synthesized via a facile one-pot hydrothermal synthesis. KCl concentration in the precursor greatly influences the crystal growth, morphology, and absorption properties of BiVO4 attributed to the effect of Clˉ ions on the formation of BiOCl intermediate and preferential growth of BiVO4 crystals along {010} planes. The photocatalytic property of BiVO4 is accordingly altered based on the KCl content. The “shuriken-like” BiVO4 prepared with 3 ​mmol of KCl exhibits the highest photocatalytic activity among our samples. Its photocatalytic rhodamine B degradation efficiency could reach 94.7% after 4 ​h of visible-light irradiation. The degradation efficiency only decreased to 90.8% after four runs of 4 h irradiation. The photodegradation rate with the shuriken-like BiVO4 is around 2.3 times higher than that with the rod-like BiVO4 prepared without KCl, owing to its highest relative intensity ratio of (040) to ( 1 ¯ 21 ) plane, which maximizes the exposed active {010} facets of BiVO4.

Hexagonal boron nitride ( h-BN) has been explored for lithium intercalation due to its similar crystal structure to graphite, a well-known anode material for Li-ion secondary batteries. Lithium h-BN intercalation compounds (Li-BNICs) have been successfully synthesized through heat treatment. In this study, potential physical properties related to electrical conductivity were investigated using pristine and milled h-BN, which is further mixed/combined with milled graphite. The electrochemical properties were characterized by cyclic voltammetry (CV) and galvanostatic cycling with potential limitation (GCPL). The chemical potential of h-BN was estimated about 1.0 V versus Li/Li + and a two-phase reaction was suggested. Accordingly, Li-BNIC is more stable than Li-GICs (lithium graphite intercalation compounds) in terms of thermal stability.

M-doped TiO 2 nanoparticles (M=Co, Mn, Ni and Zn) were synthesized by co-precipitation method combined with annealing at 500 °C for 2 h. X-ray diffraction (XRD) was used to identify their structural phases. X-ray absorption near edge structure (XANES) was conducted to probe the chemical state and crystal atomic structure of prepared samples. Magnetic properties of all samples were characterized by vibrating sample magnetrometer (VSM). The XRD analyses reveal that all samples crystallize in anatase tetragonal structure with no additional peaks. The XANES spectra exhibit triple pre-edge fingerprint of Ti4+ of oxidation state with six-fold octahedral coordinate structure. Co-, Ni- and Zn- K-edge results indicate that the Co, Ni and Zn ions in M-doped TiO 2 are in 2+ formal oxidation state. Meanwhile, Mn-doped TiO 2 sample contains the different oxidation states of 3+ and 4+. The amount of each oxidation state is confirmed by using linear combination fitting method. The magnetic measurement illustrates the paramagnetic behavior for Co-, Mn- and Ni- doped samples that strongly depend on the doping content and no hysteresis loop is observed in undoped and Zn-doped samples.

Recently, intercalation compounds with various intercalants between hexagonal boron nitride (h-BN) layers have been studied, where lithium BN intercalation compound (Li-BNIC) is one of such compounds successfully synthesized. They are expected to exhibit similar properties to lithium graphite intercalation compounds (Li-GICs) that are known as the anode material for lithium ion batteries. It is difficult, however, to apply Li-BNIC for the batteries due to its returning to an insulator when Li is deintercalated. In this study a Li–BN–graphite ternary system has been focused because it is reported that graphite-like BC2N is a promising material for rechargeable Li batteries. The primary purpose of this study is thus to investigate combined reactivity of BN and graphite with Li through milling and heating processes, and possible intercalation of Li into the matrix: h-BN, graphite or B C N. The pieces of lithium metal, h-BN and graphite powders were ball-milled using a vibratory ball-mill machine and heat-treated at 700 °C for 2 h under argon atmosphere. The samples were then characterized by X-ray diffractometry, X-ray photoelectron spectroscopy, 7Li nuclear magnetic resonance and Differential thermal analysis study. Li-GICs were mainly produced by milling, while post-annealing caused their eliminations and instead produced Li-BNICs with small amount of other lithium compounds. In terms of thermal stability, Li-BNIC is more stable than Li-GICs. In a Li–BN–graphite system, an activation energy of Li-BNIC was estimated to be 119.6 kJ/mol, which is higher than reported activation energies for Li-GICs.

This is the first report on photocatalytic properties of LnOCl (Ln = Sm, Nd) compounds, and the novel cocatalytic effect on BiOCl in highly humid environments, evaluated via the photoremoval of nitric oxide (NO).

The noble metals (Pt, Pd, Rh) supported on Cu-Ce mixed oxides with γ-Al2O3 washcoat/FeCrAl substrate were investigated as catalytic performance of Three Way Catalysts (TWC) under simulated automotive exhaust feed gas. The structural, morphological features and catalytic activity were observed by X-ray diffractometry (XRD), scanning electron microscopy (SEM), Brunauer-Emmett-Teller (BET), X-ray photoelectron spectroscopy (XPS) and GC-TCD (Varian CP-4900). The catalytic performance of noble metals (Pt, Rh, Pd) supported on Cu-Ce mixed oxides with γ-Al2O3 washcoat/FeCrAl substrate was be compared with noble metals (Pt, Rh, Pd) supported on Ce-Zr mixed oxides with γ-Al2O3 washcoat/FeCrAl substrate and only γ-Al2O3 washcoat/FeCrAl substrate at various stoichiometric ratio of oxygen. The results showed that the addition of Cu-Ce mixed oxides improved CO oxidation reaction at lower temperature during stable lambda of 1, the highest CO conversion of 99% is observed for the noble metals (Pt, Pd, Rh) support on Cu-Ce with γ-Al2O3 washcoat/FeCrAl substrate. The results also showed that, the addition of Cu-Ce mixed oxides promoted released oxygen, thus it improved strongly CO and C3H8 conversion at lean oxygen stoichiometric operation.

Aluminum-doped zinc oxide (AZO) transparent electrodes prepared by radio frequency (RF) magnetron sputtering were investigated to elucidate effects of crystal growth orientations on durability of AZO films, evaluated by electrical resistivity. During the deposition, the flow of oxygen gas was 60 sccm, while argon gas was varied from 3 to 60 sccm. As the argon gas flow increased, a transition of crystal growth orientations from (110) to (002) was observed by X-ray diffractometry (XRD). Damp heat test was conducted at 85°C and 85% of relative humidity for 25 days. As a result, the AZO films prepared with higher argon (or total) gas flows having (002) main crystal growth orientation exhibited better durability.

Transparent electrodes are widely applied in optoelectronic devices such as flat panel displays, photovoltaics, lightings, thin film transistors, etc. As the long-term usage of the devices is very important, the transparent electrodes should have good electrical stability. Al-doped ZnO (AZO) transparent electrode has been considered as the best replacement of the mostly used transparent electrode, Sn-doped In 2 O 3 (ITO), however, the electrical stability of AZO thin films is yet to be satisfactory. To improve it, this research investigated the influence of carrier concentration on the electrical stability. AZO thin films were prepared on glass substrates by RF magnetron sputtering at 100W of RF power with deposition duration of 60 minutes with a Zn metal target and 3 Al chips. Argon and oxygen gases were applied both at 30 sccm. Then thin films were annealed for 30 minutes in a hydrogen atmosphere at 400 to 550°C. After damp heat test with 85% of relative humidity at 85°C for 30 days, higher-temperature-annealed AZO thin films obtained better stability. Decrease of carrier concentration was more influential to the electrical stability than the decrease of mobility. Top oxide layer, which seemed to be spontaneously formed at higher temperature was effective to keep the carrier concentration.

Understanding the structure of energy literacy is of importance to provide an effective energy education. This article reports the difference in attributes of energy literacy by applying the energy literacy structural model proposed in our previous study through lower secondary school students in Thailand (N = 635) and Japan (N = 1070). Results indicated that Thai students scored higher than those of Japan except the basic energy knowledge and awareness of consequences. On the other hand, the amount of basic energy knowledge did not affect to increase the entire energy literacy of Japanese students. Moreover, mean values of Japan tended to decrease with the school year progression. The energy literacy model was able to support our previous outcome that the awareness of consequences plays a critical role to link between basic energy knowledge and energy-saving behavior. The social expectations or pressures may affect the structure of energy literacy of Thai students. This study suggested that the energy education required in Thailand is to enable students to derive solutions by their own critical thinking based on knowledge relevant to the energy and environmental issues. While, for Japan, it may be necessary to implement energy education as early as possible to enhance students’ awareness of consequences in an appropriate manner incorporating with family participation and visiting energy-related facility. These findings contribute the development of energy education for improving energy literacy in an effective manner.