###### Abstract
Different catalytic activity can be caused by the phase structure, catalyst surface, crystal facets with various surface atom configurations, metal loading and doping, and different physicochemical parameters [14; 15]. Furthermore, MnO\({}_{2}\) is an n-type semiconductor with oxidative catalytic [16] properties that depend upon its crystallographic forms. Each polymorph phase displays a specific tunnel structure or interlayer: 1D tunnel structure, 2D layered structure, and 3D spinel structures with different impacts on photocatalysis. Numerous studies have investigated the catalytic properties of MnO\({}_{2}\) for the degradation of organic dyes under UV and Vis irradiation and in dark conditions, reporting high degradation efficiencies [17; 18; 19; 20; 21]. As a result, scientists are focusing on less expensive and non-metal catalysts as alternatives. For example, [PERSON] et al. hydrothermally prepared one-dimensional rGO-wrapped \(\alpha\)-Mn\({}_{2}\)O\({}_{3}\)/\(\alpha\) -MnO\({}_{2}\) mixed phase electrocatalyst with improved oxygen reduction reaction activity [22]. Similarly, [PERSON] et al. hydrothermally obtained a series of CuO/\(\alpha\)-MnO\({}_{2}\) nanowire catalysts where CuO serves as the CO oxidation's active center creating a potent intermetallic synergistic effect on the surface of the -MnO\({}_{2}\) nanowire support, which increased the CO oxidation activity of \(\alpha\)-MnO\({}_{2}\). This work provides new insights into understanding the charge storage mechanism of MnO\({}_{2}\) and outlines the electrochemical characteristics of a newly manufactured \(\alpha\)-MnO\({}_{2}\)-based electrode regarding its electric double-layer capacitance, surface roughness factor, and electrochemically active surface area. Moreover, it presents a comparison between the catalytic and photocatalytic properties of \(\alpha\)-MnO\({}_{2}\), conducted with an emphasis on the rhodamine B (RhB) degradation mechanism. Rhodamine B is a xanthene, cationic dye that was selected for this study as a model organic compound because of its potential toxicity to different environmental media. Generally, the organic dyes are used in industries such as food, cosmetics, plastics, textiles, and others. The improperly treated effluents may contain dyes of significantly high concentration and can cause harming of reproductive systems, nervous systems, livers, and brains in humans and also shows toxicity to aquatic environments with mutagenic effects [23; 24; 25]. Rhodamine B is a stable dye and cannot be degraded without treatment methods such as the assistance of semiconductors under ultraviolet-visible light illumination. Many studies are found in scientific literature for the synthesis of manganese dioxide and testing for catalytic and photocatalytic activity, with a very good degradation percentage of rhodamine B in the first 90 min. In Table 1, there are presented some of the results of the catalytic and photocatalytic properties of the \(\alpha\)-MnO\({}_{2}\) and MnO\({}_{2}\) aerogel in different experimental conditions carried out in several research works. Basically, \(\alpha\)-MnO\({}_{2}\) nanostructures with well-controlled morphology and crystallinity were prepared at low temperature by a facile hydrothermal reaction. The as-obtained nanowires were investigated in terms of their structural, morphological, optical, and thermal properties. In addition to many conventional characterization methods, thermogravimetric analysis was carried out to explain the \(\alpha\)-MnO\({}_{2}\) growth mechanism. Graphite supports modified with compositions containing \(\alpha\)-MnO\({}_{2}\) were prepared and used in an electrochemical study aimed at identifying the electrode with the highest electric double-layer capacitance. Last, a catalytic study regarding the degradation of RhB in the acidic medium conditions and under solar irradiation was performed.