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"Dalam waktu 68 tahun, sel surya telah berkembang pesat dan hingga saat ini sudah terdapat tiga generasi. Sel surya generasi ketiga yang merupakan sel surya perovskite memiliki peningkatan efisiensi tercepat. Di samping pesatnya perkembangan sel surya perovskite, terdapat beberapa tantangan seperti tingginya harga bahan baku, cepatnya degradasi, dan sulitnya fabrikasi elektroda yang berbahan metal. Oleh karena itu, pengaplikasian material karbon pada sel surya dapat menjadi salah satu cara untuk mengatasi tantangan tersebut karena karbon memiliki sifat stabilitas kimia yang baik, konduktivitas elektrik yang tinggi, dan berlimpah di alam. Di sisi lain, penggabungan material karbon dan Hole Transport Material seperti CuS, CuPc, dan WO3 sudah pernah dilakukan oleh beberapa peneliti dalam upaya mengurangi biaya dan waktu fabrikasi, penyesuaian tingkat level energi, dan memperbaiki kualitas kontak permukaan. Hingga saat ini, belum ada peneliti yang meneliti tentang penggabungan CuSCN dengan elektroda berbasis karbon pada sel surya perovskite. Oleh karena itu, perlu dilakukan sebuah penelitian mengenai bagaimana proses pencampuran CuSCN dan karbon serta bagaimana karakteristik material serta kinerja sel surya perovskite yang dapat dihasilkan. Pada tesis ini, dilakukan penelitian tentang pengaruh variasi persen berat CuSCN dan variasi material karbon pada elektroda sel surya perovskite dengan struktur FTO/TiO2/perovskite/CuSCN&Carbon/FTO. Proses pencampuran CuSCN dan karbon dilakukan dengan metode Ball Mill, sedangkan proses deposisi lapisan elektroda dilakukan dengan metode Doctor Blading. Karakterisasi material dilakukan dengan pengujian Scanning Electron Microscopy dan Electrochemical Impedance Spectroscopy, sedangkan pengujian kinerja dilakukan dalam kondisi gelap dan kondisi radiasi matahari. Berdasarkan hasil optimasi persen berat CuSCN pada elektroda karbon, diperoleh hasil bahwa penambahan CuSCN sebanyak 1% pada elektroda karbon menghasilkan unjuk kerja sel surya perovskite dengan nilai Isc sebesar 0,11 mA. Berdasarkan hasil optimasi variasi material karbon, diperoleh hasil bahwa sel surya perovskite dengan elektroda campuran Carbon Nanotubes dan CuSCN dapat menghasilkan kinerja sel surya perovskite terbaik dengan Isc sebesar 0,45 mA; Voc sebesar 0,52 V; dan FF sebesar 0,37.

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Within 68 years, solar cells have grown rapidly; to date, there have been three generations. The third-generation solar cells, perovskite solar cells, have the fastest increase in efficiency. In addition to the rapid development of perovskite solar cells, there are several challenges, such as high raw material prices, rapid degradation, and difficulty fabricating metal electrodes. Therefore, applying carbon material in solar cells can be one way to overcome these challenges because carbon has good chemical stability, high electrical conductivity, and is abundant in nature. On the other hand, the incorporation of carbon materials and Hole Transport Materials such as CuS, CuPc, and WO3 has been carried out by several researchers to reduce fabrication costs and time, adjust energy levels, and improve surface contact quality. Until now, no researchers have investigated the incorporation of CuSCN with carbon-based electrodes in perovskite solar cells. Therefore, it is necessary to study how the process of mixing CuSCN and carbon and how perovskite solar cells' material characteristics and performance can be produced. In this thesis, a research was conducted on the effect of weight percent CuSCN variations in carbon material on the electrodes of perovskite solar cells with the structure of FTO/TiO2/perovskite/CuSCN&Carbon/FTO. The mixing of CuSCN and carbon was carried out using the Ball Mill method, while the electrode layer deposition process was carried out using the Doctor Blading method. Material characterization was carried out by Scanning Electron Microscopy and Electrochemical Impedance Spectroscopy, while performance testing was carried out in the dark and under solar radiation conditions. Based on the optimization results of the weight percent CuSCN on the carbon electrode, adding 1% CuSCN on the carbon electrode resulted in the performance of a perovskite solar cell with an Isc value of 0.11 mA. Based on the optimization of variations in carbon material, it is found that perovskite solar cells with a mixture of Carbon Nanotubes and CuSCN electrodes can produce the best perovskite solar cell performance with an Isc of 0.45 mA; Voc of 0.52 V; and FF of 0.37."

"Kerusakan tulang adalah salah satu penyebab utama kecacatan manusia yang secara keseluruhan menyebabkan penurunan kualitas hidup. Teknologi rekayasa jaringan telah dikembangkan untuk solusi kerusakan tulang dengan menerapkan perancah berbasis biomaterial. Berbagai material polimer alami dan sintesis dapat digunakan sebagai material perancah tulang untuk membantu adhesi dan proliferasi sel. Material konduktif berbasis karbon juga dapat dikombinasikan dalam perancah tulang dan telah diteliti dapat meningkatkan kekuatan mekanis perancah serta membantu proses pertumbuhan sel. Pada penelitian ini, dilakukan pengembangan perancah tulang menggunakan material kolagen, hydroxypropyl methylcellulose (HPMC), dan poly(vinyl alcohol) (PVA), dengan penambahan material multiwalled carbon nanotube (MWCNT) dan reduced graphene oxide (rGO). Material kolagen diekstraksi secara mandiri menggunakan metode deep eutectic solvent dari sumber ikan king kobia. Kolagen hasil ekstraksi dikarakterisasi secara fisika kimia dengan SEM, FTIR, XRD, dan DSC, dengan hasil karakterisasi menunjukkan kolagen mengandung gugus amida dan memiliki struktur triple helix khas kolagen. Dengan demikian kolagen king kobia hasil ekstraksi cocok untuk dilanjutkan sebagai material perancah. Fabrikasi perancah dilakukan menggunakan freeze-drying, kemudian dikarakterisasi secara fisika kimia dengan mengamati morfologi melalui SEM, identifikasi gugus fungsi melalui FTIR, sifat mekanik tekan, porositas, wettability, swelling, dan laju degradasi. Hasilnya menunjukkan perancah berpori dan struktur saling terhubung dengan kekuatan mekanik sekitar 9 MPa yang telah sesuai dengan tulang trabekular, porositas tinggi mencapai 90%, swelling tinggi mencapai 300% tetapi dapat tetap mempertahankan integritas perancah, laju degradasi yang sesuai dengan kehilangan massa perancah yang kurang dari 20% dalam 28 hari, serta sifat hidrofilik dengan sudut kontak air kurang dari 90o. Hasil ini menunjukkan perancah yang difabrikasi dapat menjadi kandidat yang potensial dalam aplikasi rekayasa jaringan tulang. Selain itu, karakteristik konduktivitas perancah dievaluasi melalui pengukuran elektrokimia menggunakan cyclic voltammetry (CV), menghasilkan perancah konduktif yang ditandai dengan pembentukan puncak redoks.

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Bone damage is one of the leading causes of human disability which leads to an overall decrease in quality of life. Tissue engineering technology has been developed for bone damage solutions by applying biomaterial-based scaffolds. Various natural and synthetic polymeric materials can be used as bone scaffold materials to facilitate cell adhesion and proliferation. Carbon-based conductive materials can also be combined in bone scaffolds and have been investigated to increase the mechanical strength of the scaffold and assist the cell growth process. In this research, bone scaffolds were developed using collagen, hydroxypropyl methylcellulose (HPMC), and poly(vinyl alcohol) (PVA), with the addition of multiwalled carbon nanotube (MWCNT) and reduced graphene oxide (rGO) materials. Collagen material was extracted independently using deep eutectic solvent method from king cobia fish source. The extracted collagen was characterized physically and chemically by SEM, FTIR, XRD, and DSC, with the characterization results showing that collagen contains amide groups and has a typical triple helix structure of collagen. Thus, the extracted king cobia collagen is suitable to be continued as a scaffold material. The scaffolds were fabricated using freeze-drying and characterized physically and chemically by observing morphology through SEM, functional group identification through FTIR, compressive mechanical properties, porosity, wettability, swelling, and degradation rate. The results showed porous scaffolds and interconnected structures with mechanical strength of about 9 MPa which is compatible with trabecular bone, high porosity of up to 90%, high swelling of up to 300% but still maintaining the integrity of the scaffold, suitable degradation rate with mass loss of less than 20% in 28 days, and hydrophilic properties with water contact angle of less than 90o. These results suggest the fabricated scaffold could be a potential candidate in bone tissue engineering applications. In addition, the conductivity characteristics of the scaffolds were evaluated through electrochemical measurements using cyclic voltammetry (CV), resulting in conductive scaffolds characterized by the formation of redox peaks."

"Fraktur tulang merupakan kondisi ketika kontinuitas dari tulang rusak sehingga menyebabkan perubahan pada bentuk tulang. Rekayasa jaringan tulang merupakan kombinasi dari perancah, sel, dan biofaktor dimana perancah merupakan komponen yang memainkan peranan penting. Solusi yang ditawarkan adalah memfabrikasi perancah dengan gabungan biomaterial atau komposit berupa graphite/ hydroxyapatite/ fibrin (G/HAp/F), graphene oxide/ hydroxyapatite/ fibrin (GO/HAp/F), multiwalled carbon nanotubes/ hydroxyapatite/ fibrin (MWCNT/HAp/F), dan hydroxyapatite/ fibrin (HAp/F) dengan penambahan material karbon (MWCNT, GO, dan G) sebanyak 1% wt, HAp sebanyak 2% wt, dan penambahan fibrin dengan perbandingan HAp:Fibrin senilai 20:1. Metode: Perancah disintesis dengan menggunakan metode freeze-drying. Parameter uji dilakukan melalui uji biokompatibilitas atau viabilitas sel (MTS assay), uji diferensiasi sel (pewarnaan alizarin red), dan analisa statistik. Pengujian tersebut dilakukan untuk melihat perbandingan antara keempat kombinasi perancah dalam menginduksi osteogenesis dan mempercepat proses regenerasi tulang. Hasil: Fabrikasi perancah dengan metode freeze-drying menghasilkan perancah dengan ukuran rata-rata diameter 0,68 cm dan tinggi 0,41 cm. Uji viablitas menunjukkan perancah dengan penambahan karbon menunjukkan viabilitas sel yang buruk, tidak menginduksi adhesi dan proliferasi sel, meskipun sel cenderung bermigrasi dan mendekati perancah. Uji diferensiasi menunjukkan perancah dengan penambahan karbon gagal dalam menginduksi diferensiasi sel osteogenik, Sel yang berdiferensiasi hanya ditemukan pada perancah HAp/F.

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A fracture is a condition when the continuity of the bone is broken, causing a change in the shape of the bone. Bone tissue engineering is a combination of scaffolds, cells, and biofactors where the scaffold is a component that plays an important role. In this study, scaffolds with a combination of biomaterials or composites in the form of graphite/ hydroxyapatite/ fibrin (G/HAp/F), graphene oxide/ hydroxyapatite/ fibrin (GO/HAp/F), multiwalled carbon nanotubes/ hydroxyapatite/ fibrin (MWCNT/ HAp/F), and hydroxyapatite/ fibrin (HAp/F) with the addition of carbon material (MWCNT, GO, and G) as much as 1% wt, HAp as much as 2% wt, and the addition of fibrin with a HAp:Fibrin ratio of 20:1 were fabricated. Scaffolds were synthesized using the freeze-drying method. The test parameters were carried out through biocompatibility or cell viability test (MTS assay) and cell differentiation test (alizarin red staining), and statistical analysis. The test was conducted to see the comparison between the three combinations of scaffolds in inducing osteogenesis and accelerating the process of bone regeneration. The scaffold fabrication using the freeze-drying method resulted in a scaffold with an average diameter of 0.68 cm and an average height of 0.41 cm. Viability test showed that the scaffolds with the addition of carbon showed poor cell viability, did not induce cell adhesion and proliferation, although cells tended to migrate and approach the scaffold. Differentiation test showed that the scaffolds with addition of carbon failed to induce osteogenic cell differentiation. Differentiated cells were only found in the HAp/F scaffold."

"Fraktur tulang merupakan kondisi kerusakan pada sebagian atau seluruh kontinuitas tulang yang dapat menyebabkan beberapa komplikasi seperti infeksi, pendarahan, kerusakan pada saraf dan pembuluh darah, dan defek. graphine oxide/hidroksiapatit/fibrin, functionalized graphite/hidroksiapatit/fibrin, functionalized multiwalled carbon nanotubes/hidroksiapatit/fibrin, dan hidroksiapatit/fibrin perancah HAp/F memiliki ukuran pori 0,5 – 4,1 μm, GO/HAp/F 2,6 – 6,1 μm, fG/HAp/F 0,7 – 14,1 μm dan fMWCNT/HAp/F 1,5 – 11,1 μm. Terdapat gugus PO43- , O-H, C-H, C-O alifatik, dan amida I pada setiap kelompok perancah. Dengan penambahan gugus fungsi C=O pada perancah dengan penambahan material karbon. Nilai kekuatan tekan pada perancah GO/HAp/F, fG/HAp/F, dan fMWCNT/HAp/F sesuai dengan kekuatan tekan cancellous bone. Persentase porositas paling besar padaperancah GO/HAp/F sebesar 9,99 ± 2,85%. Perancah GO/HAp/F memiliki persentase swelling yang paling tinggi dan laju degradasi yang paling lambat. Sedangkan retensi yang paling baik ditunjukkan oleh perancah fG/HAp/F dengan persentase 8,27%. Berdasarkan keseluruhan hasil, perancah HAp/F dengan penambahan material GO mempunyai karakteristik fisika-kimia yang lebih baik pada penelitian ini dibandingkan dengan perancah fMWCNT atau fG.

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A fracture is a condition when the continuity of the bone is broken causing several complications such as infection, bleeding, damage to nerves and blood vessels, and disability. In this research, the solution offered is to fabricate a scaffold with a combination of biomaterials or composites in the form of graphine oxide/hydroxyapatite/fibrin, functionalized graphite/hydroxyapatite/fibrin, functionalized multiwalled carbon nanotubes/hydroxyapatite/fibrin, and hydroxyapatite/fibrin. Scaffolds were synthesized using the freeze-drying method. This study aims to determine the physico-chemical characteristics of the four groups of scaffolds. Based on the results of SEM-EDS, the HAp/F scaffold has a pore size of 0.5 – 4.1 μm, GO/HAp/F has 2.6 – 6.1 μm, fG/HAp/F has 0.7 – 14.1 μm and fMWCNT/HAp/F has 1.5 – 11.1 μm. There were PO43- , O-H, C-H, aliphatic C-O and amide I groups in each scaffold. Additionally the C=O functional group on the scaffold with the addition of carbon material. The compressive strength values of GO/HAp/F, fG/HAp/F, and fMWCNT/HAp/F scaffolds correspond to the compressive strength of the cancellous bone. The highest percentage of porosity is GO/HAp/F scaffolds with 9.99 ± 2.85%. GO/HAp/F scaffolds had the highest swelling percentage and the slowest degradation rate. Meanwhile, the best retention was shown by fG/HAp/F scaffold with a percentage of 8.27%. Based on the overall results, the HAp/F scaffold with the addition of GO material had better physico-chemical characteristics in this study than fMWCNT or fG scaffolds."