Electronic Theses and Dissertation

Penelitian ini bertujuan untuk mengkarakterisasi Cu2O/CuO-NP yang direduksi dengan Citrus maxima untuk mengevaluasi aktivitas fotokatalitiknya model sikat botol untuk mendegradasi zat pewarna metilen biru dengan cahaya matahari. Hasil uji UV-Vis didapatkan λmax larutan sintesis pada 500 nm. Hasil uji XRD didapatkan puncak 2θ = 29,60°, 36,37°, 42,30°, 61,48°, dan 73,61° yang menunjukkan keberadaan Cu2O dan ukuran kristal adalah 7,46 nm. Hasil uji FTIR didapatkan pita serapan pada 835 cm⁻¹ dan 624 cm⁻¹ merupakan karakteristik Cu–O stretching. Uji SEM menunjukkan Cu2O/CuO-NP yang terimmobilisasi pada monofilamen nilon memiliki bentuk irregular. Hasil uji mikroskop optik menunjukkan ketebalan Cu2O/CuO-NP pada monofilamen nilon sebesar 29,855 µm. Hasil uji PSA menunjukkan bahwa ukuran partikel rata-rata Cu₂O/CuO-NP yaitu sekitar 940 nm. Pengujian aktivitas fotokatalis dilakukan menggunakan larutan metilen biru 5 ppm sebanyak 400 mL dengan λmax 664 nm. Hasil persentase degradasi larutan metilen biru kondisi terang tanpa katalis sebesar 20,98% dan kondisi gelap pakai katalis sebanyak 0,9 g yaitu 50,09%. Hasil persentase degradasi larutan metilen biru disinari cahaya matahari dengan variasi jumlah katalis didapatkan 14,45% (0,9 g), 13,68% (0,72 g), 20,95% (0,54 g) dan 47,29% (0,36 g) pada menit ke-120. Berdasarkan hasil penelitian diketahui bahwa ekstrak Citrus maxima berhasil mereduksi ion Cu²⁺ menjadi Cu₂O/CuO, dan katalis yang terbentuk dalam model sikat botol menunjukkan aktivitas fotokatalitik yang signifikan terhadap degradasi metilen biru. Oleh karena itu, sistem ini berpotensi sebagai solusi ramah lingkungan untuk pengolahan limbah zat warna menggunakan cahaya matahari.

Kata kunci: Monofilamen Nilon, Ekstrak Kulit Jeruk Bali, Degradasi

This research aims to characterize Cu₂O/CuO-NP reduced using Citrus maxima and to evaluate their photocatalytic activity in a bottle-brush model for the degradation of methylene blue dye under sunlight. The UV-Vis test results showed that the synthesized solution had a λmax at 500 nm. The XRD analysis revealed peaks at 2θ = 29.60°, 36.37°, 42.30°, 61.48°, and 73.61°, indicating the presence of Cu₂O and the crystal size is 7.46 nm. The FTIR analysis showed absorption bands at 835 cm⁻¹ and 624 cm⁻¹, which are characteristic of Cu–O stretching. SEM analysis revealed that the immobilized Cu₂O/CuO nanoparticles on the nylon monofilament exhibited an irregular shape. Optical microscope analysis showed that the Cu₂O/CuO-NP layer on the nylon monofilament had a thickness of 29.855 µm. PSA results showed that the average particle size of Cu₂O/CuO-NP was approximately 940 nm. The photocatalytic activity test was conducted using 400 mL of 5 ppm methylene blue solution with a λmax of 664 nm. The degradation percentage of methylene blue under light exposure without a catalyst was 20.98%, while under dark conditions with 0.9 g of catalyst, the degradation reached 50.09%. The percentage of degradation under light conditions with varying amounts of catalyst was 14.45% (0.9 g), 13.68% (0.72 g), 20.95% (0.54 g), and 47.29% (0.36 g) at 120 minutes. Based on the results, it was found that Citrus maxima extract successfully reduced Cu²⁺ ions into Cu₂O/CuO, and the resulting catalyst in the bottle brush model exhibited significant photocatalytic activity toward the degradation of methylene blue. Therefore, this system has potential as an environmentally friendly solution for dye wastewater treatment using sunlight. Keywords: Nylon Monofilament, Pomelo Peel Extract, Degradation