Hybrid organic–inorganic perovskite (HOIP) photovoltaics have emerged as a promising new technology for the next generation of photovoltaics since their first development 10 years ago, and show a high-power conversion efficiency (PCE) of about 29.3%. The power-conversion efficiency of these perovskite photovoltaics depends on the base materials used in their development, and methylammonium lead iodide is generally used as the main component. Perovskite materials have been further explored to increase their efficiency, as they are cheaper and easier to fabricate than silicon photovoltaics, which will lead to better commercialization. Even with these advantages, perovskite photovoltaics have a few drawbacks, such as their stability when in contact with heat and humidity, which pales in comparison to the 25-year stability of silicon, even with improvements are made when exploring new materials. To expand the benefits and address the drawbacks of perovskite photovoltaics, perovskite–silicon tandem photovoltaics have been suggested as a solution in the commercialization of perovskite photovoltaics. This tandem photovoltaic results in an increased PCE value by presenting a better total absorption wavelength for both perovskite and silicon photovoltaics. In this work, we summarized the advances in HOIP photovoltaics in the contact of new material developments, enhanced device fabrication, and innovative approaches to the commercialization of large-scale devices.

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<p><em>Dye sensitized solar cells</em> (DSSCs) merupakan teknologi alternatif fotovoltaik yang menguntungkan. DSSCs menunjukkan harga yang murah, efisiensi yang tinggi dan proses pembuatan yang sederhana. Dalam aplikasi DSSCs, fotoanoda memiliki peranan yang penting untuk mengumpulkan elektron-elektron yang tereksitasi dan dye berfungsi untuk menyalurkan cahaya elektron-elektron ke <em>transparent conducting film</em> (TCF). Fotoanoda mempunyai <em>band gap</em> yang lebar pada semikonduktor logam oksida (contoh: <em>zinc oxide</em> (ZnO) dan <em>titanium dioxide</em> (TiO₂)) yang dilapiskan pada TCF. Counter electrode (CE) adalah salah satu komponen yang penting dalam proses kerja DSSCs. CE digunakan sebagai mediator untuk membangkitkan <em>sensitizer</em> setelah masuknya elektron. Bahan CE yang ideal harus mempunyai resistansi yang rendah, biaya produksi yang murah, konduktivitas listrik yang tinggi, aktivitas elektrokatalitik yang bagus dan stabilitas yang tinggi. Bahan-bahan CE yang umum digunakan untuk aplikasi DSSCs yaitu seperti platina (Pt), karbon, <em>carbon nanotubes</em> (CNTs), grafin dan polimer konduktif. Review ini dikembangkan untuk mempelajari sifat-sifat bahan fotoanoda dan CE yang bagus untuk aplikasi DSSCs. Review ini juga digunakan untuk memberikan informasi untuk perkembangan bahan-bahan fotoanoda dan CE pada penelitian selanjutnya dalam aplikasi DSSCs. Dalam review ini, pengaruh bahan-bahan yang digunakan untuk fotoanoda dan CE dalam aplikasi DSSCs didiskusikan.</p>

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<p class="AbstractText">This work investigated the effect of post-annealing treatment on the fabrication of zinc oxide (ZnO) thin film by spraying deposition method. Based on SEM analysis, the annealed ZnO thin film at 400˚C presented better uniformity as compared to the non-annealed film. Further measurement by UV-Vis revealed that the lowest optical band gap energy (<em>E_g</em>) (3.22 eV) was achieved by 400˚C sample. These results confirmed that post-annealing treatment enhanced the optical and morphological properties of the fabricated ZnO thin film.</p>

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The use of a smartphone as a mobile learning tool in schools is controversial. On the one hand, the teacher prohibits it because it would interfere with the learning process in the classroom; and on the other hand, the teacher saw a lot of potentials can be used from mobile technology. The goal of this study is to describe how the development of secondary schools in Indonesia can facilitate students through the use of mobile learning with the hope that it can be taken at the school level policies to strengthen the existing learning system so that students can achieve optimal learning competencies. This research used descriptive qualitative evaluations to make observations on the application of mobile learning in several secondary schools in several regions in Indonesia during 2015. The results of this study indicate that some of the schools that have implemented mobile learning have a tendency that mobile learning was not planned and structured as a school program; so that the advantages of mobile technology has not been effectively used. Two important things to solve this condition are the availability of government policy and improving teachers literacy in managing mobile learning application.