In their manuscript, the authors investigate the effect of ultraviolet ozone (UV-ozone) treatment on thermally-evaporated molybdenum oxide (MoOx) as a hole transport material in non-fullerene acceptor (NFA) organic solar cells based on the PM6:Y6 blend. The study provides a comprehensive comparison between PEDOT:PSS, untreated MoOx, and UV-ozone-treated MoOx layers, including detailed optical, electrical, and morphological characterizations of the films, as well as the optoelectronic analysis of the devices. Furthermore, the authors extend their investigation to solar cells based on the PM6:L8-BO blend, achieving a peak efficiency of 16.85%.

The manuscript is well-written, with a clear presentation of the experimental results and conclusions. The paper is logically structured, and the discussion is easy to follow. I have some concerns about the novelty of the study, as the beneficial effects of UV-ozone treatment on transition-metal-based films are well-known for optoelectronic devices such as organic solar cells and OLEDs. However, the authors partially address this point in the introduction by highlighting the lack of studies focused on NFA-based OSCs, which may justify the contribution of the work.

A key missing aspect that needs to be addressed before the paper can be accepted is the stability analysis of the non-treated MoOx devices. Currently, all comparisons are made against PEDOT:PSS, which is well-known for its limited stability. To strengthen the manuscript's novelty and impact, it would be important to demonstrate the benefits of the UV-ozone treatment specifically in comparison to non-treated MoOx films.

Additionally, I suggest a few minor revisions to enhance the accuracy of the data presentation. Given that the main focus of the paper is the comparison of various device performance metrics, it would be important to consistently report error bars throughout the manuscript. This includes Tables 2 and 3, Kelvin probe measurements, atomic force microscopy, DC conductivity measurements (where significant digits are currently misreported), hole mobility measurements, and charge collection probability.

Once the authors have satisfactorily addressed my comments, the paper can be suitable for publication in the Journal of Materials Chemistry A.

The authors have adequately addressed my previous comments, and I now consider the paper suitable for publication in Journal of Materials Chemistry A.