Champion Device Architectures for Low-Cost and Stable Single-Junction Perovskite Solar Cells.

High power conversion efficiencies (PCE), low energy payback time (EPBT), and low manufacturing costs render perovskite solar cells (PSCs) competitive; however, a relatively low operational stability impedes their large-scale deployment. In addition, state-of-the-art PSCs are made of expensive materials, including the organic hole transport materials (HTMs) and the noble metals used as the charge collection electrode, which induce degradation in PSCs. Thus, developing inexpensive alternatives is crucial to fostering the transition from academic research to industrial development. Combining a carbon-based electrode with an inorganic HTM has shown the highest potential and should replace noble metals and organic HTMs. In this review, we illustrate the incorporation of a carbon layer as a back contact instead of noble metals and inorganic HTMs instead of organic ones as two cornerstones for achieving optimal stability and economic viability for PSCs. We discuss the primary considerations for the selection of the absorbing layer as well as the electron-transporting layer to be compatible with the champion designs and ultimate architecture for single-junction PSCs. More studies regarding the long-term stability are still required. Using the recommended device architecture presented in this work would pave the way toward constructing low-cost and stable PSCs.

Mono- and Multicomponent Biosorption of Caffeine and Salicylic Acid onto Processed Cape Gooseberry Husk Agri-Food Waste.

There is an increasing need to find cost-effective and sustainable solutions for treating wastewater from contaminants of emerging concern (CECs). In this regard, cape gooseberry husk-typically an agri-food waste-is investigated for the first time as a potential biosorbent for the removal of model pharmaceutical contaminants of caffeine (CA) and salicylic acid (SA) from water. Three different preparations of husks were investigated and characterized using Fourier transform infrared spectroscopy, scanning electron microscopy, Brunauer-Emmett-Teller analysis, zeta potential, and point of zero charge measurements. The activation of the husk led to an increase in the surface area, pore volume, average pore size, and adsorption favorability. The single-component adsorption of SA and CA onto the three husks was investigated at different initial concentrations and pH values to determine the optimal operating conditions. The maximal removal efficiencies of SA and CA reached up to 85 and 63%, respectively, for the optimal husk which also offers a less energy-intensive option in its activation. This husk also exhibited high rates of adsorption that exceeded other husk preparations by up to four times. It was proposed that CA interacts electrostatically with the husk, while SA binds through weak physical interactions (e.g., van der Waals and H-bonding). In binary systems, CA adsorption was highly favored over SA adsorption, owing to its electrostatic interactions. The selectivity coefficients αSACA varied with initial concentration and ranged between 61 and 627. The regeneration of husk was also successful resulting in its re-use for up to four full consecutive cycles, further demonstrating the efficiency of cape gooseberry husk use in wastewater treatment.

Supercapattery electrode materials by Design: Plasma-induced defect engineering of bimetallic oxyphosphides for energy storage.

Although transition metal hydroxides are promising candidates as advanced supercapattery materials, they suffer from poor electrical conductivity. In this regard, previous studies have typically analyzed separately the impacts of defect engineering at the atomic level and the conversion of hydroxides to phosphides on conductivity and the overall electrochemical performance. Meanwhile, this paper uniquely studies the aforementioned methodologies simultaneously inside an all-in-one simple plasma treatment for nickel cobalt carbonate hydroxide, examines the effect of altering the nickel-to-cobalt ratio in the binder-free defect-engineered bimetallic Ni-Co system, and estimates the respective quantum capacitance. Results show that the concurrent defect-engineering and phosphidation of nickel cobalt carbonate hydroxide boost the amount of effective redox and adsorption sites and increase the conductivity and the operating potential window. The electrodes exhibit ultra-high-capacity of 1462 C g-1, which is among the highest reported for a nickel-cobalt phosphide/phosphate system. Besides, a hybrid supercapacitor device was fabricated that can deliver an energy density of 48 Wh kg-1 at a power density of 800 W kg-1, along with an outstanding cycling performance, using the best performing electrode as the positive electrode and graphene hydrogel as the negative electrode. These results outperform most Ni-Co-based materials, demonstrating that plasma-assisted defect-engineered Ni-Co-P/POx is a promising material for use to assemble efficient energy storage devices.