Search

The paper and pulp industry stands out to be one of the industries that are growing at a fast pace. Besides their characteristics such as high water consumption of 695.7 million m3 per year and subsequent high energy consumption, there are plenty of environmental impacts arising from this industry. Approximately 300 different types of harmful organic pollutants such as phenols, dioxins, and other organic substances are the significant effluents of the paper and pulp industry. As per the regulations set by the world health organization (WHO), the permissible limit of such pollutants is less than 1 ppm. Since the complete degradation of these pollutants is difficult to achieve using conventional techniques, advanced oxidation processes (AOPs) are widely being used as promising alternatives. On the other hand, depleting non-renewable energy resources are forcing industries to look for energy-efficient technologies. Photocatalysis is one such AOPs, which has the potential to solve the energy-wastewater nexus and is the primary focus of this review in terms of waste treatment from the paper and pulp industry. The photocatalytic materials induce photoreactions by receiving photon energy from light. However, harnessing light energy to the fullest is a challenge owing to the limited share of UV spectrum in sunlight. Different composite photocatalysts at different loadings, pollutant concentrations, and contact time along with their respective efficiencies are reported. The enhancement in thermodynamic driving force due to shift in Fermi energy levels with a suitable example is explained. The dependence of photocatalysis on various factors such as organic species, temperature, and light intensity makes it tough to predict the precise kinetic model in real-life experiments. The hydrogen production from the degradation of organic pollutants was discussed vividly and by optimization of the processes, an estimated amount of 0.45% of the total world's energy could be produced from the paper and pulp industry alone. [ABSTRACT FROM AUTHOR]

Paper, in addition to its frequent usage in writing, packaging, printing, etc., has gained comprehensive utility as a flexible and conductive base in sensors, solar energy harvesting, conversion, and storage applications. This is due to its strategic-aiding aspect in terms of environmental friendliness, cost-effectiveness, recyclability, thin, flexible and lightweight nature, biocompatibility, etc., required to develop next-generation flexible devices. The signs of progress in paper-based devices are seen in matured technologies of the paper-based sensor for varied sectors. Also, there have been wide-ranging research efforts on developing paper-based high-performance energy harvesting, conversion, and storage solutions. However, it is a newly emerging area and needs a fundamental and state-of-the-art understanding for future devices development. Thus, the current review summarizes the research progress in this field utilizing paper, understanding fundamental properties w.r.t application, performance enhancement w.r.t material advancements (i.e. paper modification), and technological trends, which is otherwise not yet reviewed earlier. It further sheds light upon the perspectives for their associated and allied technological developments in the energy sector. [Display omitted] • Role of paper properties in energy related applications are discussed. • Paper based electrodes for energy harvesting and conversion devices. • Utilty of papers in energy storage i.e. supercapacitors and batteries is presented. • Challenges and perspectives of realization of paper based devices for energy sector are projected. [ABSTRACT FROM AUTHOR]