Synthesis of High-Quality Bulk Single-Crystal Black Phosphorus by the Circulating Vapor Growth Approach.

Black phosphorus (BP), a promising two-dimensional (2D) layered semiconductor material, has gained enormous attention due to its impressive properties over the past several years. Although plenty of methods have been developed to synthesize high-quality BP, most of the currently available BP materials still suffer from unsatisfactory crystallization, purity, and stability in air, hindering their practical application. A facile approach to synthesizing ultrahigh-quality single-crystal BP is of significance to shed light on the nature of 2D semiconductor materials and their massive application. In this work, we present the facile and efficient circulating vapor growth approach to growing bulk single-crystal BP. The as-grown BP material features high crystallinity and ultrahigh purity (higher than 99.999 at %), exceeding those of all the previously reported and some commercially available BP crystals. It also maintains excellent stability in air and water after 15 consecutive days of test. Moreover, the as-synthesized BP material features good thermal stability, oxidation resistance, and excellent electrical properties, as well. This study provides a new approach for the fabrication of ultrahigh-quality BP material and thus promotes its application.

Compressive strain induced superior HER performance of nickel in alkaline solution.

The HER requires a highly efficient, cost-effective, and stable catalyst to adapt to the large-scale hydrogen industry. Nickel has been confirmed to be useful to drive the water splitting reaction, but the intrinsic performance remains unsatisfactory. In this work, nickel (EG-Ni) with compressive strain was prepared through a one-step electrochemical deposition strategy. It shows an outstanding enhancement for the HER, and it achieves a current density of 10 mA cm-2 at a low overpotential of 85.9 mV. A long-term durability test proves that the EG-Ni can tolerate a large current density of 100 mA cm-2, and the overpotential remains steady without dramatically increasing. Such a low overpotential and superior stability are attributed to the optimized adsorption energy on the catalyst surface, as evidenced by the downshifted position of the d-band center.

[Reform of collective forest property in Liaoning Province: a discussion].

The reform of collective forest property has increased the farmers' income, and brought new development to forestry. On the basis of expatiating the conception of collective forest property and related management system, this paper introduced in detail the course, main ways, and effects of the reform in Liaoning Province, analyzed the research progress of the reform and existing problems, and made appraisement and exceptions to the reform of collective forest property in Liaoning Province, aimed to give comments to the development and orientation of forward reform. In this province, the reform of collective forest property had the characteristics of classified reform, different reform types in different areas, and the main and affiliated reform being carried out at the same time. By the end of 2009, the main task had turned into affiliated reform. In the future, the reform should be focused on the optimal forestry management model to improve the forest economic, ecological, and social benefits, and using multi-disciplinary methods to strengthen the researches on the relationships between forestry management and forest ecological functions to provide scientific bases for the reform of collective forest property in Liaoning Province.