Implementasi Film Tipis Ba0.5Sr0.5TiO3 Didadah Mangan dan Sensor DHT22 pada Sistem IoT untuk Monitoring Kondisi Cahaya dan Suhu

Abstract

Penelitian ini mengembangkan sensor cahaya film tipis Ba0.5Sr0.5TiO3 (BST) yang didadah mangan (Mn), diintegrasikan dengan sensor suhu DHT22 dalam sistem monitoring berbasis Internet of Things (IoT). Film tipis BST-Mn dengan variasi pendadah 0%, 0,5%, dan 1% disintesis melalui Chemical Solution Deposition, spin coating, dan annealing 550°C, lalu dikarakterisasi meliputi ketebalan, XRD, UV-Vis, dan I-V. Sistem dirancang menggunakan ESP32 terintegrasi ADS1115, DHT22, dan buzzer, dengan tampilan data real-time melalui dashboard website. Hasil menunjukkan ketebalan film 17,2–31,2 nm, band gap 2,13–3,27 eV, dan sampel 0,5% Mn menghasilkan tegangan keluaran fotodioda tertinggi (27,9 mV). Sensitivitas sensor tertinggi pada sampel 1% Mn (15,35%), suhu tetap stabil dengan selisih 0,1–0,4°C. Sistem berhasil mengintegrasikan kedua sensor secara real-time, menunjukkan potensi BST didadah Mn untuk sistem monitoring lingkungan berbasis IoT.

This research developed a light sensor based on manganese-doped Ba0.5Sr0.5TiO3 (BST) thin film, integrated with a DHT22 temperature sensor in an Internet of Things (IoT)-based monitoring system. BST-Mn thin films with dopant variations of 0%, 0.5%, and 1% were synthesized via Chemical Solution Deposition, spin coating, and annealing at 550°C, then characterized for thickness, XRD, UV-Vis, and I-V properties. The system was designed using an ESP32 microcontroller integrated with an ADS1115 module, DHT22 sensor, and buzzer, displaying real-time data through a website dashboard. Results showed film thickness of 17.2–31.2 nm, a band gap of 2.13–3.27 eV, and the 0.5% Mn sample produced the highest photodiode output voltage (27.9 mV). The highest sensor sensitivity was obtained for the 1% Mn sample (15.35%), while temperature remained stable with a difference of 0.1–0.4°C. The system successfully integrated both sensors in real time, demonstrating the potential of Mn-doped BST for IoT-based environmental monitoring systems.