Kumar Manoj, Pandey Purnendu Shekhar, Reddy M Sudhakara, Gehlot Anita, Choudhary Santosh Kumar, Singh Gyanendra Kumar, Singh Balkeshwar
MLR Institute of Technology, Hyderabad, India.
Department of Electronics and Communication Engineering, G.L. Bajaj Institute of Technology and Management, Greater Noida-, Uttar Pradesh, India.
PLoS One. 2025 Jul 3;20(7):e0326657. doi: 10.1371/journal.pone.0326657. eCollection 2025.
This study investigates the optical and electronic properties of SnOx/Graphene Oxide (SnOx/GO) heterostructures, focusing on their sensitivity and selectivity to methane adsorption and its tunable light absorption capabilities across different wavelength ranges. By categorizing SnOx/GO heterostructures into four types based on the oxygen mole fraction (x) of SnOx, notable differences are observed in their light absorption, extinction coefficient, and reflectance. Among these, Type-C heterostructures demonstrate the highest absorption coefficient (1.8 × 10⁵ cm ⁻ ¹), indicating strong potential for UV and visible light applications. Building upon the optimized Type-C SnOx/GO heterostructure, we further examine the effect of varying concentrations of methane molecules adsorbed on its surface. This leads to the classification of four additional heterostructure types- Type-I to Type-IV which are based on the methane molecules concentration adsorbed on the surface of an optimized SnOx/GO heterostructure. The interaction with methane further modulates the optoelectronic properties of heterostructure, with Type-II heterostructures demonstrating the highest extinction coefficient (8.0 at 1000 nm) and strong near-infrared absorption. In contrast, Type-IV structures, characterized by the highest methane concentration, show a significant increase in reflectance (~0.85) and a reduction in absorption. Additionally, an energy distribution analysis of various atmospheric gases, such as CH₄, H₂O, and CO₂ were conducted to evaluate the selectivity of SnOx/GO heterostructure based sensors. The aim was to ensure minimal interference from other ambient gases. The analysis revealed that CH₄ exhibits a more negative energy state, indicating higher stability and a greater affinity for adsorption on the sensor surface compared to the other atmospheric gases. This stabilization highlights the interaction dynamics of the material, reinforcing its potential for diverse applications, including UV absorption, infrared transparency, and trace methane detection. Overall, these findings establish SnOx/GO heterostructures, particularly the Type-C variant with an optimal oxygen mole fraction (x), as promising candidates for advanced optical and methane gas-sensing technologies.
本研究调查了氧化锡/氧化石墨烯（SnOx/GO）异质结构的光学和电子特性，重点关注其对甲烷吸附的灵敏度和选择性，以及在不同波长范围内可调的光吸收能力。通过根据SnOx的氧摩尔分数（x）将SnOx/GO异质结构分为四种类型，观察到它们在光吸收、消光系数和反射率方面存在显著差异。其中，C型异质结构表现出最高的吸收系数（约1.8×10⁵ cm⁻¹），表明在紫外和可见光应用方面具有强大潜力。基于优化后的C型SnOx/GO异质结构，我们进一步研究了其表面吸附不同浓度甲烷分子的影响。这导致了另外四种异质结构类型的分类——I型至IV型，它们基于优化后的SnOx/GO异质结构表面吸附的甲烷分子浓度。与甲烷的相互作用进一步调节了异质结构的光电特性，II型异质结构表现出最高的消光系数（在1000 nm处约为8.0）和强烈的近红外吸收。相比之下，以最高甲烷浓度为特征的IV型结构，反射率显著增加（约0.85），吸收减少。此外，对各种大气气体（如CH₄、H₂O和CO₂）进行了能量分布分析，以评估基于SnOx/GO异质结构的传感器的选择性。目的是确保来自其他环境气体的干扰最小。分析表明，CH₄表现出更负的能量状态，表明与其他大气气体相比，其稳定性更高，对传感器表面的吸附亲和力更大。这种稳定性突出了材料的相互作用动力学，增强了其在包括紫外线吸收、红外透明和痕量甲烷检测等多种应用中的潜力。总体而言，这些发现确立了SnOx/GO异质结构，特别是具有最佳氧摩尔分数（x）的C型变体，作为先进光学和甲烷气体传感技术的有前途的候选材料。
