Carbon is the central element driving the evolution of our human society towards prosperity over several historical stages.As for now,we are in a stage of blossoming sciences and technologies related to carbon materia...Carbon is the central element driving the evolution of our human society towards prosperity over several historical stages.As for now,we are in a stage of blossoming sciences and technologies related to carbon materials,as a result of which our evergrowing energy demand has been largely satisfied.Yet,the expected rise of carbon energy consumption and the emerging environmental concerns have prevented us from being optimistic.To build a sufficiently powered future,we have been revolutionizing our ways of carbon energy utilization by discovering and designing new carbon structures,exploring and enhancing their unique physicochemical properties,and pursuing environmentally friendly strategies.Emerging structures such as graphene and sp-bonded C18 have allowed us to discover carbon’s promising properties such as energy storage and superconductivity,while green energy solutions such as fuel cells and CO2 reduction are working synergistically to purify the ecospheric carbon cycle.Therefore,this essay timely discusses related carbon sciences and technologies that have been the milestones shaping our energy consumption,based on which our energy future can be envisioned to be green and prosperous.展开更多
太阳能驱动水裂解产氢是一种绿色能源技术,用于制备可再生和零碳排放燃料以实现可持续能源生产.近期,氮化碳(g-C_(3)N_(4))同素异形体C_(3)N_(5)的出现克服了g-C_(3)N_(4)的固有缺点,如光生载流子快速复合和可见光吸收差,而导致极低的...太阳能驱动水裂解产氢是一种绿色能源技术,用于制备可再生和零碳排放燃料以实现可持续能源生产.近期,氮化碳(g-C_(3)N_(4))同素异形体C_(3)N_(5)的出现克服了g-C_(3)N_(4)的固有缺点,如光生载流子快速复合和可见光吸收差,而导致极低的光催化效率.本文将硼掺杂剂通过原子替换或间隙掺杂的方式引入到C_(3)N_(5)体系中,并利用密度泛函理论对纯C_(3)N_(5)和硼掺杂C_(3)N_(5)体系进行计算,考察了硼原子对C_(3)N_(5)电子和光学性能的影响以及其催化析氢反应(HER)机理.热力学计算结果表明,硼原子掺杂在C_(3)N_(5)体系中是可行且有利的.在N_(3)位氮原子被硼原子取代(BN_(3)-C_(3)N_(5))后,带隙(0.6 e V)变窄.与纯C_(3)N_(5)相比,硼掺杂剂通过Volmer Tafel和Volmer Heyrovsky机制降低了酸性和碱性介质中HER反应中决定步骤的反应能垒.BN_(3)-C_(3)N_(5)表面的氢吸附吉布斯自由能(0.11 e V)与Pt/C催化剂(-0.09 e V)相当.综上,非金属掺杂碳可提高氮化物的催化性能,对未来该方向研究提供一定借鉴.展开更多
In this paper, we propose a novel hybrid sp-sp2 monoclinic carbon allotrope mC12. This allotrope is a promising light metallic material, the mechanical and electronic properties of which are studied based on first-pri...In this paper, we propose a novel hybrid sp-sp2 monoclinic carbon allotrope mC12. This allotrope is a promising light metallic material, the mechanical and electronic properties of which are studied based on first-principles calculations. The structure of this new mC12 is mechanically and dynamically stable at ambient pressure and has a low equilibrium density due to its large cell volume. Furthermore, calculations of the elastic constants and moduli reveal that mC12 has a rigid mechanical property. Finally, it exhibits metallic characteristics, owing to the mixture of sp-sp2 hybrid carbon atoms.展开更多
基金DOE Office of Energy Efficiency and Renewable Energy,Vehicle Technologies OfficeDOE Office of Science by UChicago Argonne,Grant/Award Number:DE‐AC02‐06CH11357。
文摘Carbon is the central element driving the evolution of our human society towards prosperity over several historical stages.As for now,we are in a stage of blossoming sciences and technologies related to carbon materials,as a result of which our evergrowing energy demand has been largely satisfied.Yet,the expected rise of carbon energy consumption and the emerging environmental concerns have prevented us from being optimistic.To build a sufficiently powered future,we have been revolutionizing our ways of carbon energy utilization by discovering and designing new carbon structures,exploring and enhancing their unique physicochemical properties,and pursuing environmentally friendly strategies.Emerging structures such as graphene and sp-bonded C18 have allowed us to discover carbon’s promising properties such as energy storage and superconductivity,while green energy solutions such as fuel cells and CO2 reduction are working synergistically to purify the ecospheric carbon cycle.Therefore,this essay timely discusses related carbon sciences and technologies that have been the milestones shaping our energy consumption,based on which our energy future can be envisioned to be green and prosperous.
文摘太阳能驱动水裂解产氢是一种绿色能源技术,用于制备可再生和零碳排放燃料以实现可持续能源生产.近期,氮化碳(g-C_(3)N_(4))同素异形体C_(3)N_(5)的出现克服了g-C_(3)N_(4)的固有缺点,如光生载流子快速复合和可见光吸收差,而导致极低的光催化效率.本文将硼掺杂剂通过原子替换或间隙掺杂的方式引入到C_(3)N_(5)体系中,并利用密度泛函理论对纯C_(3)N_(5)和硼掺杂C_(3)N_(5)体系进行计算,考察了硼原子对C_(3)N_(5)电子和光学性能的影响以及其催化析氢反应(HER)机理.热力学计算结果表明,硼原子掺杂在C_(3)N_(5)体系中是可行且有利的.在N_(3)位氮原子被硼原子取代(BN_(3)-C_(3)N_(5))后,带隙(0.6 e V)变窄.与纯C_(3)N_(5)相比,硼掺杂剂通过Volmer Tafel和Volmer Heyrovsky机制降低了酸性和碱性介质中HER反应中决定步骤的反应能垒.BN_(3)-C_(3)N_(5)表面的氢吸附吉布斯自由能(0.11 e V)与Pt/C催化剂(-0.09 e V)相当.综上,非金属掺杂碳可提高氮化物的催化性能,对未来该方向研究提供一定借鉴.
基金This work was financially supported by the National Natural Science Foundation of China (Grant No. 11204007), the 111 Project (B17035), tile Natural Science New Star of Science and Technologies Research Plan in Shaanxi Province of China (Grant No. 2017KJXX-53), and Education Com- mittee Natural Science Foundation in Shaanxi Province of China (Grant No. 16JK1049). Xiao-Feng Shi is acknowledged for help- fill discussions and comments on the manuscript. All the authors thank the computing facilities at the High Performance Computing Center of Xidian University.
文摘In this paper, we propose a novel hybrid sp-sp2 monoclinic carbon allotrope mC12. This allotrope is a promising light metallic material, the mechanical and electronic properties of which are studied based on first-principles calculations. The structure of this new mC12 is mechanically and dynamically stable at ambient pressure and has a low equilibrium density due to its large cell volume. Furthermore, calculations of the elastic constants and moduli reveal that mC12 has a rigid mechanical property. Finally, it exhibits metallic characteristics, owing to the mixture of sp-sp2 hybrid carbon atoms.