Elemental two-dimensional (2D) materials, characterized by unique chemical, physical, and electrical characteristics, now offer intriguing energy and catalysis application possibilities. Their 2D thin structure has constricting effects due to their large surface-to-volume ratios, good transport features, and fascinating the physicochemical characteristics. Despite the fact, that emerging elemental 2D materials such as graphene, borophene, silicone, black phosphorene, antimonene, tellurene, bismuthene, and arsenene, etc., are receiving significant attention in electronics and optoelectronic devices, as well as multiple energy storage and conversion systems, due to their remarkable structural, and electronic characteristics. Particularly, 2D materials have large surface areas, elevated theoretical capacities, structural anisotropy, excellent mobility, and tunable bandgaps, which are intriguing prospects for a variety of energy storage and conversion techniques. As main group elements such as silicon and germanium have favored the area of contemporary electronics, their monolayer 2D intermediates have shown considerable potential for next-generation electronic metals and potentially game-changing features for optoelectronics, energy, and beyond. Such atomically thin materials have expressed interesting characteristics like near-room-temperature topological insulation in bismuthene, exceptionally elevated electron mobilities in phosphorene and silicone, and significant Li-ion storage capacity in borophene. Recent advancements in the synthesis, analysis and use of several developing 2D materials have been noteworthy. We have demonstrated the basic properties, structure, importance of imperfections and functionalization, explanation of various allotropes, general structure-property correlations, categorization of conjugated polymers, and most recent advancements in the synthesis of 2D materials and their application in various sustainable diversity. In this view, we highlight the advancement of new elemental 2D materials in terms of synthesis techniques, characteristics, synthesis schemes and merit figures in energy production and catalyst purposes. In addition, we contribute our perspective on the problems and possibilities, which we hope will shed light on the enormous prospects of this ever-expanding industry.