Nickel Oxide/Graphene Oxide (NiO/GO) as Double Hole Transport Layer in Perovskite Solar Cell

The hole transport layer is one of the most crucial parts of the perovskite solar cell. Recently, some studies have improved perovskite solar cell performance by modifying the surface of the hole transport layer using double fabrication of inorganic-organic materials. Their studies generate higher power conversion efficiency than inorganic materials but have not generated good stability. Therefore, this study aims to develop a double-hole transport layer using nickel oxide (NiO) and graphene oxide (GO) to improve the perovskite solar cells performance. The experiment utilizes the spin-coating method to observe the effect of combining NiO and GO in perovskite solar cells. The experimental results showed that the double hole transport layers produce better power conversion efficiency of 15.3% compared to single-layer NiO. The double holes can smoothen the holes of the perovskite interface layer and cause molecular uniformity to reduce recombination. In addition, NiO/GO surfaces show better stability to environmental conditions

Pengaruh Penggunaan Katalis (Zeolit) Terhadap Kinetic Rate Tar Hasil Pirolisis Serbuk Kayu Mahoni (Switenia Macrophylla)

This research was conducted to find out the influence of the use of a catalyst (zeolite) against kinetic rate results of tar pyrolysis of sawdust mahogany. research process undertaken experimentally with temperature 523K and 873K on the heating rate 673 K/hour. pyrolysis is done for 3 hours with wood powder particle size 0,5 – 1 mm. before use activated zeolite in advance by means of heated at a temperature of 400 °c for 1 hour. the results showed the value of kinetic rate tar with zeolites greater than without zeolites , where the value of the kinetic rate equation obtained i.e. = 185,49. −2779/ (heating rate 673 K/hour without zeolite) and = 93,037. (heating rate 673 K/hour with zeolite). The results of the validation shows the value addition in the calculation of the volume is already approaching the actual value

Purifikasi Biogas Dengan Variasi Ukuran Dan Massa Zeolit Terhadap Kandungan CH4 Dan CO2

Nowadays, the development of the renewable energy very rapidly. It is driven by the nature of the renewable energy that has been proven to be cleaner than conventional energy, so an increase in the use of renewable energy continues to rise. Biogas is produced from biological processes (anaerobic digester) is capable of producing gas such as CH 4 , CO 2 , H 2 S, and other gases. Therefore it is very important to make the process of refining the biogas. In this research, using the biogas purification process purification method stratified, with a solution of sodium hydroxide with zeolite is purified again and again purified with activated charcoal, hence the storied purification. In this study focused on the observation of zeolite as an adsorbent, the size of the fine and coarse zeolite, and zeolite are varied mass of 50 grams, 100 grams and 150 grams. In 60 minutes, the best result obtained on zeolites fine size with a mass of 150 grams of CO 2 obtained down to 4.07%, but the pressure dropped to 0.65 kPa. With the size of the coarse zeolite at 4.26% CO 2 , with a pressure drop of 0.84 kPa. After the purification process, zeolite proved to be hidrofill with the content of the zeolite fine biggest water with 5.4%

Pengaruh Temperatur Larutan Triethylamine (Tea), Air Dan Ca(OH) 2 Terhadap Pelepasan CO 2 Pada Proses Pemurnian Biogas

Biogas is renewable fuel that generated by bacteria activities in anaërobic organic matter process. Biogas composed by CH 4 17 (54% to 70%), CO2 (27% to 45%) and impurities gas such as N2 , H2O, CO, H2S. The CO2 on biogas should be reduced because it's as inhibitor that reduces heat of biogas flame. This research proposed to reduce CO 2 in the packed column purification system by using TEA, H2O, and Ca(OH)2 solution as absorber.The absorber temperature were variated 35o, 45o, 55omand 65oC for knowing performance absorber reduce CO2 at the flow rate of CO 2 and CH4 , entering packed collum by 0.1 l/m, release time of CO2 in heater was eight minutes by comparison CH4 , and CO2 i.e. 80 % -20 %, 85 % -15 %, 90 % -10 % and 95 % -5 %. The result of this study was the higher the temperature heating, the higher the percentage of CO2 released. Absorbentt TEA + H2O and combined TEA + H2O + Ca(OH)2 , improve absorption of CO2 in a linear manner at a temperature of warming 35, 45, 55, 65 c

Pengaruh Variasi Temperatur Terhadap Kuantitas Char Hasil Pirolisis Serbuk Kayu Mahoni (Switenia Macrophylla) Pada Rotary 39 Kiln

Pirolysis is thermochemical decomposition process of biomass into useful product. One kind of method that can be used is a Rotary Kiln pirolyzer which is consist a heating cylinder that rotates with a certain rotation speed. This research is aimed to get the effect of temperature due to Char product quantity of switenia macrophylla Rotary Kiln pirolysis.The research has done by pirolysis experiment with 200 gram of switenia macrophylla in dust form. Temperature was varied 250 C, 350 o C, 450 o C, 500 o C, and 600 C. The heating temperature was provided by eletric heater with control system. Temperatur was measured with K type thermocouple. The heating process has taken for 180 minutes using stopwatch. The measurement has done for biomass and Char volume using measuring cup. Mass was measured by using mass scale. Low heating value was measured by using bomb calorimeter. The result show that the temperature has effect due to Char product of switenia macrophylla Rotary Kiln pirolysis. The loss of Char mass is tend to increase due to temperature increases. Low heating value and Char porosity is tend to increase due to mass loss percentage increases. Shrinking factor and percentage of yield energy is tend to decrease due to mass loss percentage increasing

Karakteristik Produksi Browns Gas Dengan Menggunakan Tenaga Matahari

Renewable energy has potentials to be developed to meet our energy needs in the future. One promising energy source is browns gas. Browns gas is a mixture of di-atomic and mono-atomic of hydrogen and oxygen. One effort to produce browns gas is through the process of electrolysis of water. However, the process of electrolysis still considered a process uneconomical and inefficient, since the energy of electrochemical decomposition of water is relatively high. Thus, the challenge of brown gas production is reducing electrical energy. In this study, we propose to use solar energy for browns gas production plant, since the solar energy is environmentally friendly energy sources available so abundant in Indonesia. The experiment was carried out in two methods. First, the electrolysis was done using electricity produced by the solar panel directly without voltage control. The second method, the voltage of electricity from the solar panel was controlled using a regulator then it used for the water electrolysis. The results show that the direct method generates fluctuative electricity with the rate power of 29.67 Watt. This electricity was used for electrolysis process and produced brown gas 0,1393 g for 4 hours. On the other hand the in-direct method generated power relatively constant at 18.3 Watt and produced the brown gas about 0.1365 g

The Effect of Water Salinity and Radiation Intensity to the Temperature Distribution and Evaporation Rate inside Porous Media

In the coastal areas, there are found many cases of clean water crisis; the most reasonable solution is to use the solar still from salty seawater. Sea salt concentration levels vary widely in each region depending on ecological conditions and materials carried by the river. This study aims to analyze the effect of salinity and radiation intensity towards the evaporation rate. Several parameters, such as the difference in the mass of the specimen, surface temperature, and evaporation rate were observed. The evaporation rate data shows that concrete with ferrous sand aggregate (particle size of 0.125 mm) has the highest value in which the thermal conductivity value of this specimen is of the highest value as well. Higher salt addition and radiation cause the temperature value that each specimen generated to become higher. Therefore, the FS125, which is concrete with 0.125 mm ferrous sand aggregate, has the best capability of porous media in the absorbent plate of solar still application