Direct exposure to solar irradiation (ultraviolet, visible, and infrared) is correlated with several harmful implications, such as biological damage in humans and material adulteration [1]. A wide variety of products, especially pharmaceutically active compounds, food, and soft drinks are sensitive to UV light and visible light exposure. Products exposed to sunlight may suffer from ramifications such as the increase in temperature, which results in the deterioration of their quality. Appropriate packaging materials have been developed to protect products from light exposure during transportation or storage [2]. 

Sensor-based logistics (SBL) uses various sensors to offer real-time data about different environmental conditions such as temperature, light exposure, relative humidity, and barometric pressure. The accumulative dose of light exposure can be defined with optoelectronic devices or with chemical probes that undergo various physicochemical transformations (oxidation/reduction, decomposition, photocleavage, dimerization, polymerization, etc.) upon exposure to UV irradiation [3]. This approach has been extensively followed to detect the exposure level of human skin to UV irradiation of solar light.

This work unveils a novel application of a common packing material, “bubble wraps” (Aeroplast), as a tool to measure visible sunlight exposure [4]. We have synthesized and meticulously characterized a layered metal selenide photocatalyst with the general formula (DMAH)_2xMn_xSn_3–xSe₆ (DMSe-1) (x= 1.3-1.7; DMAH⁺=dimethylammonium), featuring a narrow band gap of 0.76 eV. Subsequently, a photochemically sensitive probe based on this new catalyst, an indicator dye, and a reducing agent was prepared to assess exposure to visible light directly. The probe is introduced into air-filled bubble wrap compartments, where it undergoes photocatalytic degradation to provide a chromatic response to sunlight exposure. The probe's sensitivity to variable irradiation dose is customizable by adjusting the amount of the photocatalyst, while the color intensity is directly proportional to the absorbed irradiation dose. 

The results from the new photoactive material show a strong correlation with those from standard sunlight pyranometers (r = 0.98, p=0.05), proving that bubble wraps, in addition to their protective function, can effectively serve as a visible light sensor with an average error of <15%. Furthermore, the study's findings mark a significant step forward in the use of metal chalcogenides as visible light sensors, offering promising prospects for the development of new light-sensitive materials.