Carbon Energy

Để cải thiện hiệu suất quang xúc tác của quang xúc tác nguyên bản, các phương pháp phổ biến như pha tạp nguyên tố, xây dựng hợp chất và chế tạo cấu trúc nano mới đã được công nhận là các phương pháp điều chỉnh hiệu quả. Các phương pháp này đã được thực nghiệm xác nhận là có hiệu quả trong nhiều ứng dụng quang xúc tác trên các quang xúc tác khác nhau. Tính toán lý thuyết hàm mật độ (DFT) là một công cụ mạnh mẽ và cơ bản để xác định cơ chế nội tại của hoạt động quang xúc tác được nâng cao. Và nó đạt được mức độ chính xác từ nguyên tử, phân tử đến các đơn vị tế bào. Trong nghiên cứu này, tiến bộ nghiên cứu tính toán DFT gần đây của các hệ thống gốm nit rít cacbon graphit dựa trên s-triazine (g–C₃N₄) làm quang xúc tác được tóm tắt. Cụ thể, chúng tôi thu thập thông tin về vị trí pha tạp, năng lượng hình thành, các tính chất hình học và điện tử. Chúng tôi cũng thảo luận về hiệu ứng cộng hưởng của hàm làm việc, mức Fermi và vị trí bờ dải trên trường điện từ xây dựng sẵn, lộ trình chuyển giao các vật dẫn điện quang sinh và cơ chế quang xúc tác (loại truyền thống II hoặc cấu trúc năng lượng bù trực tiếp Z). Hơn nữa, chúng tôi đã phân tích cấu hình hình học, cấu trúc băng tần, và độ ổn định của các dạng nano g–C₃N₄ như nano cụm, nano dải, và ống nano. Cuối cùng, triển vọng tương lai trong việc tiết lộ lý thuyết sâu hơn về các quang xúc tác dựa trên g–C₃N₄ được đề xuất.

Nowdays, electrocatalytic water splitting has been regarded as one of the most efficient means to approach the urgent energy crisis and environmental issues. However, to speed up the electrocatalytic conversion efficiency of their half reactions including hydrogen evolution reaction (HER) and oxygen evolution reaction (OER), electrocatalysts are usually essential to reduce their kinetic energy barriers. Electrospun nanomaterials possess a unique one‐dimensional structure for outstanding electron and mass transportation, large specific surface area, and the possibilities of flexibility with the porous feature, which are good candidates as efficient electrocatalysts for water splitting. In this review, we focus on the recent research progress on the electrospun nanomaterials‐based electrocatalysts for HER, OER, and overall water splitting reaction. Specifically, the insights of the influence of the electronic modulation and interface engineering of these electrocatalysts on their electrocatalytic activities will be deeply discussed and highlighted. Furthermore, the challenges and development opportunities of the electrospun nanomaterials‐based electrocatalysts for water splitting are featured. Based on the achievements of the significantly enhanced performance from the electronic modulation and interface engineering of these electrocatalysts, full utilization of these materials for practical energy conversion is anticipated.

Currently, more than 86% of global energy consumption is still mainly dependent on traditional fossil fuels, which causes resource scarcity and even emission of high amounts of carbon dioxide (CO₂), resulting in a severe “Greenhouse effect.” Considering this situation, the concept of “carbon neutrality” has been put forward by 125 countries one after another. To achieve the goals of “carbon neutrality,” two main strategies to reduce CO₂emissions and develop sustainable clean energy can be adopted. Notably, these are crucial for the synthesis of advanced single‐atom catalysts (SACs) for energy‐related applications. In this review, we highlight unique SACs for conversion of CO₂into high‐efficiency carbon energy, for example, through photocatalytic, electrocatalytic, and thermal catalytic hydrogenation technologies, to convert CO₂into hydrocarbon fuels (CO, CH₄, HCOOH, CH₃OH, and multicarbon [C₂₊] products). In addition, we introduce advanced energy conversion technologies and devices to replace traditional polluting fossil fuels, such as photocatalytic and electrocatalytic water splitting to produce hydrogen energy and a high‐efficiency oxygen reduction reaction (ORR) for fuel cells. Impressively, several representative examples of SACs (includingd‐,ds‐,p‐, andf‐blocks) for CO₂conversion, water splitting to H₂, and ORR are discussed to describe synthesis methods, characterization, and corresponding catalytic activity. Finally, this review concludes with a description of the challenges and outlooks for future applications of SACs in contributing toward carbon neutrality.

The development of an efficient catalyst for formic acid electrocatalytic oxidation reaction (FAEOR) is of great significance to accelerate the commercial application of direct formic acid fuel cells (DFAFC). Herein, palladium phosphide (Pd_xP_y) porous nanotubes (PNTs) with different phosphide content (i.e., Pd₃P and Pd₅P₂) are prepared by combining the self‐template reduction method of dimethylglyoxime‐Pd(II) complex nanorods and succedent phosphating treatment. During the reduction process, the self‐removal of the template and the continual inside–outside Ostwald ripening phenomenon are responsible for the generation of the one‐dimensional hollow and porous architecture. On the basis of the unique synthetic procedure and structural advantages, Pd₃P PNTs with optimized phosphide content show outstanding electroactivity and stability for FAEOR. Importantly, the strong electronic effect between Pd and P promotes the direct pathway of FAEOR and inhibits the occurrence of the formic acid decomposition reaction, which effectively enhances the FAEOR electroactivity of Pd₃P PNTs. In view of the facial synthesis, excellent electroactivity, high stability, and unordinary selectivity, Pd₃P PNTs have the potential to be an efficient anode electrocatalyst for DFAFC.

Green energy generation is an indispensable task to concurrently resolve fossil fuel depletion and environmental issues to align with the global goals of achieving carbon neutrality. Photocatalysis, a process that transforms solar energy into clean fuels through a photocatalyst, represents a felicitous direction toward sustainability. Eco‐rich metal‐free graphitic carbon nitride (g‐C₃N₄) is profiled as an attractive photocatalyst due to its fascinating properties, including excellent chemical and thermal stability, moderate band gap, visible light‐active nature, and ease of fabrication. Nonetheless, the shortcomings of g‐C₃N₄ include fast charge recombination and limited surface‐active sites, which adversely affect photocatalytic reactions. Among the modification strategies, point‐to‐face contact engineering of 2D g‐C₃N₄ with 0D nanomaterials represents an innovative and promising synergy owing to several intriguing attributes such as the high specific surface area, short effective charge‐transfer pathways, and quantum confinement effects. This review introduces recent advances achieved in experimental and computational studies on the interfacial design of 0D nanostructures on 2D g‐C₃N₄ in the construction of point‐to‐face heterojunction interfaces. Notably, 0D materials such as metals, metal oxides, metal sulfides, metal selenides, metal phosphides, and nonmetals on g‐C₃N₄ with different charge‐transfer mechanisms are systematically discussed along with controllable synthesis strategies. The applications of 0D/2D g‐C₃N₄‐based photocatalysts are focused on solar‐to‐energy conversion via the hydrogen evolution reaction, the CO₂ reduction reaction, and the N₂ reduction reaction to evaluate the photocatalyst activity and elucidate reaction pathways. Finally, future perspectives for developing high‐efficiency 0D/2D photocatalysts are proposed to explore potential emerging carbon nitride allotropes, large‐scale production, machine learning integration, and multidisciplinary advances for technological breakthroughs.