@article{AFLAHA2026108729,

title = {Performance evaluation and DFT study of a room temperature methylamine gas sensor based on QCM with Fe3O4-PVAc nanofiber active layer},

author = {Rizky Aflaha and Arif Lukmantoro and Selly Andaresta and Ghissani Mulan and Chlara Naren Maharani and Finantius Enrico M. Rahangiar and Yuliyan Dwi Prabowo and Aditya Rianjanu and Moh. Adhib Ulil Absor and Kuwat Triyana and Roto Roto and Witha Berlian Kesuma Putri},

url = {https://www.sciencedirect.com/science/article/pii/S2468023026003184},

doi = {https://doi.org/10.1016/j.surfin.2026.108729},

issn = {2468-0230},

year  = {2026},

date = {2026-04-01},

urldate = {2026-01-01},

journal = {Surfaces and Interfaces},

volume = {86},

pages = {108729},

abstract = {The negative impact of methylamine gas, which has the potential to harm the environment and human health, necessitates reliable sensors capable of detecting it at room temperature. The research developed a methylamine gas sensor based on a quartz crystal microbalance (QCM) with an active layer of polyvinyl acetate (PVAc) nanofibers and surface-modified with Fe3O4. PVAc nanofiber was fabricated using the electrospinning method, and then deposited with Fe₃O₄ using the dropcasting method. The PVAc nanofibers exhibited a smooth and continuous morphology and did not undergo damage after Fe₃O₄ deposition. The detection of Fe mass in the deposited nanofiber also confirmed the success of Fe₃O₄ addition. The sensor with Fe₃O₄ showed a significantly higher response to methylamine (51.5 Hz at 120 ppm) compared to the PVAc sensor (29.5 Hz at 120 ppm). The sensor also exhibits a high sensitivity of 0.442 Hz·ppm⁻¹ with a limit of detection of 9.2 ppm. In addition, Fe₃O₄ also accelerates the response and recovery times, while maintaining good selectivity and long-term stability. Furthermore, the density functional theory (DFT) calculations reveal stable adsorption energy, notable charge transfer, and short adsorption distances between methylamine and the Fe₃O₄ surface through Fe–N bonds. These findings indicate the strong gas-surface interaction, which is well-aligned with experimental results. This study demonstrates that the fabricated sensor exhibits reliable performance and has great potential as a room temperature methylamine gas sensor with high sensitivity and selectivity.},

keywords = {Density functional theory, FeO, Methylamine, Nanofiber, openQCM, Polyvinyl acetate, Quartz Crystal Microbalance},

pubstate = {published},

tppubtype = {article}

}

@article{10.1063/5.0242516,

title = {The fabrication of PVP/NiAc nanofiber as a QCM active layer for hazardous vapor detection},

author = {Riris Sukowati and Yadi Mulyadi Rohman and Bertolomeus Haryanto Agung and Aan Priyanto and Dian Ahmad Hapidin and Khairurrijal Khairurrijal},

url = {https://doi.org/10.1063/5.0242516},

doi = {10.1063/5.0242516},

issn = {0094-243X},

year  = {2025},

date = {2025-02-20},

urldate = {2025-01-01},

journal = {AIP Conference Proceedings},

volume = {3197},

number = {1},

pages = {020002},

abstract = {The detection of hazardous vapors is crucial for controlling their pollution in the environment. The Quartz crystal microbalance (QCM) stands out as a high-performance sensing device that features high sensitivity, simplicity, low cost, and the ability to operate at room temperature. In this study, a QCM has been coated with a new active layer of PVP/NiAc composite nanofibers to detect hazardous vapor. The QCM surface is coated with PVP/NiAC nanofiber which is fabricated using the electrospinning method. The morphology and average diameter of PVP/NiAc composite nanofibers were investigated utilizing an optical microscope and ImageJ software, respectively. The developed composite nanofibers have an average diameter of 989 ± 172.61 nm. The fabricated sensor was tested against methanol, acetone, dimethylacetamide (DMAc), and formaldehyde vapors in different concentrations ranging from 5.0 to 22.5 ppm. The sensitivities of QCM sensors with PVP/NiAc nanofiber active layer were 2.35, 0.62, 0.32, and 0.29 Hz/ppm for methanol, formaldehyde, acetone, and DMAc, respectively. The developed sensor performed the highest sensitivity and frequency shift response in detecting methanol vapors. Furthermore, the adsorption phenomena were investigated by adapting several adsorption models, including Scatchard, Freundlich, Langmuir, and Langmuir–Freundlich, to validate the physical adsorption affinity. In conclusion, the QCM sensors based on PVP/NiAc composite nanofibers can be a considerable way to detect hazardous vapors, especially methanol, in various sensing applications.},

keywords = {Electrospinning, Nanofiber, openQCM, Physisorption, Quartz Crystal Microbalance},

pubstate = {published},

tppubtype = {article}

}

@article{as2024investigation,

title = {Investigation of the Multiple Doping of Citric Acid and Chitosan in Nanofiber for Enhancement of a Quartz Crystal Microbalance-Based Ammonia Sensor},

author = {Ahmad Hasan As’ ari and Rizky Aflaha and Laila Katriani and Ahmad Kusumaatmaja and Rike Yudianti and Kuwat Triyana},

url = {https://link.springer.com/article/10.1007/s11664-024-11646-0},

doi = {https://doi.org/10.1007/s11664-024-11646-0},

year  = {2024},

date = {2024-12-19},

urldate = {2024-12-19},

journal = {Journal of Electronic Materials},

pages = {1--13},

publisher = {Springer},

abstract = {Herein, the use of multiple doping of citric acid (CA) and chitosan (CS) in polyacrylonitrile (PAN) nanofibers over a quartz crystal microbalance is investigated as a method for enhancing the performance of an ammonia sensor at room temperature. It was found that the PAN/CA/CS sensor has superior sensitivity and better selectivity. The PAN/CA/CS sensor demonstrated sensitivity of (0.629 ± 0.005) Hz ppm−1, which increased by 2.75 times compared to the PAN/CA sensor and 39 times compared to the PAN sensor. Chitosan doping also resulted in better selectivity, as shown by the decreased response of the PAN/CA/CS sensor compared to the PAN/CA sensor to other analytes including formaldehyde (−147%), acetic acid (−22%), ethanol (−19%), methanol (−15%), and acetone (−1%). The viscoelastic properties of chitosan might be responsible for the anti-Sauerbrey phenomena behind the enhanced selectivity. The detection and adsorption mechanisms of the fabricated sensors towards ammonia were studied using adsorption kinetics and isotherms. The adsorption kinetics varied and exhibited the limits of the high-concentration region of each sensor. Moreover, all the fabricated sensors followed the Freundlich adsorption isotherm with different adsorption processes, which were confirmed by scanning electron microscopy, x-ray diffraction, and Fourier transform infrared spectroscopy concerning the morphology, crystal structure, and active groups after the loading of citric acid and chitosan. Thus, the use of multiple doping can improve the sensor abilities, as well as causing changes in the detection and adsorption mechanisms.},

keywords = {Adsorption, Ammonia, Chitosan, Nanofiber, openQCM, QCM, Quartz Crystal Microbalance},

pubstate = {published},

tppubtype = {article}

}

@article{KATRIANI2024111532,

title = {Nanofiber-coated quartz crystal microbalance with chitosan overlay for highly sensitive room temperature ammonia gas sensor},

author = {Laila Katriani and Rizky Aflaha and Ahmad Hasan As’ari and Pekik Nurwantoro and Roto Roto and Kuwat Triyana},

url = {https://www.sciencedirect.com/science/article/pii/S0026265X24016448},

doi = {https://doi.org/10.1016/j.microc.2024.111532},

issn = {0026-265X},

year  = {2024},

date = {2024-11-01},

urldate = {2024-11-01},

journal = {Microchemical Journal},

volume = {206},

pages = {111532},

abstract = {Ammonia is toxic and can pose health risks. Ensuring the safety of individuals working with or around ammonia sensors is crucial, adding complexity to the design and use of such sensors. An ammonia gas sensor by quartz crystal microbalance coated with chitosan-overlaid polyvinyl acetate (PVAc) nanofiber has been studied to have high performance in both sensitivity and selectivity. The scanning electron microscope (SEM) and Fourier-transform infrared (FTIR) spectroscopy were used to analyze the sensing surface, which was the electrospun PVAc nanofiber with chitosan overlay. The nanofiber showed a morphological change and had a more active layer after being overlaid by chitosan. The estimation of PVAc nanofiber thickness on the QCM sensor is (12.0 ± 2.1) µm, measured using a digital microscope. The QCM sensor deposited with PVAc nanofiber only had a sensitivity of 0.076 Hz·ppm−1. It improved to 3.012 Hz·ppm−1 after overlaid with 0.7 wt% chitosan (denoted as PVAc/Ch7 sensor), an increase of 39.6 times. Moreover, the PVAc/Ch7 sensor had a rapid response and recovery times of 9 and 35 s with a very low detection limit of 0.526 ppm. The sensor also exhibited good selectivity toward other analytes. In addition, the sensor also had outstanding in other performances, such as linearity, repeatability, reversibility, and excellent long-term stability. This proposed QCM-based ammonia sensor could be an alternative to analyzing ammonia in various fields.},

keywords = {Ammonia, Chitosan, Nanofiber, openq, openQCM sensors, PVAc, QCM},

pubstate = {published},

tppubtype = {article}

}

@article{khoirudin2023influence,

title = {Influence of the SMN antibody on quartz crystal microbalance with dissipation (QCM-D) surface as an SMN protein biosensor},

author = {Hanif Khoirudin and Rizky Aflaha and Eldiana Rully Arsetiyani and Ari Dwi Nugraheni and Dian Kesumapramudya Nurputra and Kuwat Triyana and Ahmad Kusumaatmaja},

year  = {2023},

date = {2023-11-06},

urldate = {2023-01-01},

journal = {MRS Communications},

pages = {1--7},

publisher = {Springer},

abstract = {The lack of survival motor neuron (SMN) protein levels can lead to spinal muscular atrophy (SMA) disease. In this study, an SMN protein biosensor based on quartz crystal microbalance with dissipation (QCM-D) was developed. The sensor was coated with polyvinyl alcohol (PVA) nanofiber and doped with SMN antibodies to increase the sensitivity. Scanning electron microscope (SEM) images showed that the nanofiber was undamaged after doping the SMN antibody. The sensitivity of the QCM-D sensor was 21.2 Hz/% after doping SMN antibodies and had good stability for 3 days. Moreover, the sensor has been validated using western blot. Thus, the fabricated QCM-D-based biosensor has excellent potential in detecting SMN levels in human blood plasma.},

key = {QCM-D, openQCM, Quartz Crystal Microbalance, neuron, protein, antibodies, nanofiber, SEM},

keywords = {antibody detection, Nanofiber, Nanofibers, neuron, openQCM, protein, QCM-D, Quartz Crystal Microbalance, SEM},

pubstate = {published},

tppubtype = {article}

}

@article{aflaha2022improving,

title = {Improving ammonia sensing performance of quartz crystal microbalance (QCM) coated with nanofibers and polyaniline (PANi) overlay},

author = {Rizky Aflaha and Henny Afiyanti and Zhafirah Nur Azizah and Hanif Khoirudin and Aditya Rianjanu and Ahmad Kusumaatmaja and Roto Roto and Kuwat Triyana},

url = {https://www.sciencedirect.com/science/article/pii/S2590137022001935},

doi = {https://doi.org/10.1016/j.biosx.2022.100300},

year  = {2022},

date = {2022-12-23},

urldate = {2022-01-01},

journal = {Biosensors and Bioelectronics: X},

pages = {100300},

publisher = {Elsevier},

abstract = {Ammonia gas sensors with high sensitivity, good selectivity, and superior stability continue to be developed to monitor ammonia levels in the air. In this study, we developed a sensor based on a quartz crystal microbalance coated with polyvinyl acetate (PVAc) nanofiber overlaid with a polyaniline (PANi) nanocomposite to increase the sensitivity and selectivity of the sensor. The morphology and chemical composition of the fabricated nanofibers were examined by scanning electron microscopy and Fourier transform infrared spectroscopy. PANi nanocomposites were shown to stick to nanofiber, and nanofiber became many active groups after PANi overlay. The QCM sensor coated with the PVAc nanofiber overlaid with 0.05% PANi (PVAc/PANi5) exhibited the highest sensitivity of 0.297 Hz/ppm. This value was increased 5.2 times compared to the sensor without the PANi overlay (0.055 Hz/ppm). The PVAc/PANi5 sensor exhibited good reproducibility, repeatability, and reversibility. Moreover, a rapid response (36 s) and recovery (26 s) time were observed. The sensor also showed good selectivity towards other analytes and was proven to have good long-term stability during two months of testing. This finding may potentially be an alternative method for increasing the ammonia-sensing performance of a sensor through overlaying.},

key = {Polyvinyl acetate, Polyaniline, Ammonia, Quartz crystal microbalance, Nanofiber},

keywords = {Ammonia, Nanofiber, Polyaniline, Polyvinyl acetate, Quartz Crystal Microbalance},

pubstate = {published},

tppubtype = {article}

}