Nitrate reduction to ammonia (NRA) is critical and attractive for environmental remediation and energy conservation. Copper represents one of the most promising non-noble-metal NRA electrocatalysts while its intrinsic catalytic activity of facets and pH influence remain unclear. Using density functional theory calculations, nitrate reduction to ammonia pathways are evaluated on low-index crystal surfaces, Cu(111), Cu(100), and Cu(110), at different pH. Systematic thermodynamic and kinetic analysis indicates that the pathway NO3 – → *NO3 → *NO2 → *NO → *NOH → *NHOH → *NH → *NH2 → *NH3 → NH3(g) is the most probable in all pH ranges, ending a long-standing debate on NRA pathways. Both the catalytic deoxygenation and hydrogenation processes in NRA are substantially affected by pH. Thus, the rate-determining steps and overpotentials exhibit pH-dependent characteristics. Besides, it is found that the pH influences the competition between the hydrogen evolution reaction (HER) and NRA. By considering NRA and HER on different surfaces, we found that Cu(100) and Cu(111) contribute most to NRA other than Cu(110). Specifically, in near-neutral and alkaline environments, Cu­(111) exhibits the best NO3 – to NH3 performance, while Cu(100) is more effective in a strong acidic environment. This result rationalizes recent experimental observations. The NRA activity differences of copper surfaces are attributed to the local coordination environment and electronic states of surface atoms. Thanks to a stereospecific Cu–Cu couple, both strong *NOH adsorption and weak *NH3 adsorption are realized on Cu(111) and Cu(100), facilitating superior NRA.

Context: Naringin is a natural flavanone glycoside that is found in the Chinese herbal medicines and citrus fruits. Studies have demonstrated that naringin possesses numerous biological and pharmacological properties, but few reviews of these studies have been performed. Objective: The present review gathers the fragmented information available in the literature describing the extraction of naringin, its pharmacology and its controlled release formulations. Current research progress and the therapeutic potential of naringin are also discussed. Methods: A literature survey for relevant information regarding the biological and pharmacological properties of naringin was conducted using Pubmed, Sciencedirect, MEDLINE, Springerlink and Google Scholar electronic databases from the year 2007-2015. Results: Naringin modulates signalling pathways and interacts with signalling molecules and thus has a wide range of pharmacological activities, including anti-inflammatory, anti-cancer activities, as well as effects on bone regeneration, metabolic syndrome, oxidative stress, genetic damage and central nervous system (CNS) diseases. Information was gathered that showed the extraction of naringin can be improved using several modifications. There has been some progress in the development of controlled release formulations of naringin. Conclusion: Naringin is a promising candidate for further in vivo studies and clinical use. More detailed studies regarding its mechanism of action are required. ARTICLE HISTORY

performance, superior flexibility, vivid colors, unique transparency, potential lowcost production with solution processing, etc. [1][2][3][4][5][6][7][8][9] The recent years have witnessed a great leap in device performance and device stability, which are attributed to the delicate molecular structure design, advanced morphology manipulation technology, and device structure evolution. [10][11][12][13][14][15][16][17][18][19] Currently, the best-performed OPVs exhibit a certified efficiency of 19.3% for single junction device and 20.0% for tandem structure, as well as an extrapolated device stability with T 80 over 30 years. [20][21][22] While compared to their inorganic counterparts (e.g., for siliconbased PVs, the efficiency is over 26%), the OPVs are still inferior in efficiency. [23] Therefore, it would be urgent to further improve the device efficiency of OPV, which will require an in-depth understanding on the working principles of OPV, as well as the development of effective strategies to balance the charge generation, transport, and recombination. Among all the strategies, it is generally observed that adding a third component to construct the ternary blend is a very simple but effective method to further boost the device performance of OPVs. [24][25][26][27][28][29][30][31][32] A bunch of benefits have been demonstrated with the multicomponentThe ternary blend is demonstrated as an effective strategy to promote the device performance of organic photovoltaics (OPVs) due to the dilution effect. While the compromise between the charge generation and recombination remains a challenge. Here, a mixed diluent strategy for further improving the device efficiency of OPV is proposed. Specifically, the high-performance OPV system with a polymer donor, i.e., PM6, and a nonfullerene acceptor (NFA), i.e., BTP-eC9, is diluted by the mixed diluents, which involve a high bandgap NFA of BTP-S17 and a low bandgap NFA of BTP-S16 (similar with that of the BTP-eC9). The BTP-S17 of better miscibility with BTP-eC9 can dramatically enhance the open-circuit voltage (V OC ), while the BTP-S16 maximizes the charge generation or the short-circuit current density (J SC ). The interplay of BTP-17 and BTP-S16 enables better compromise between charge generation and recombination, thus leading to a high device performance of 19.76% (certified 19.41%), which is the best among single-junction OPVs. Further analysis on carrier dynamics validates the efficacy of mixed diluents for balancing charge generation and recombination, which can be further attributed to the more diverse energetic landscapes and improved morphology. Therefore, this work provides an effective strategy for highperformance OPV for further commercialization.

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