We herein report a versatile and environmentally friendly electrochemical oxidative C–H phosphonylation protocol.

Most of the current methods for the synthesis of two-dimensional materials (2DMs) require temperatures not compatible with traditional back-end-of-line (BEOL) processes in semiconductor industry (450 °C). Here, we report a general BiOCl-assisted chemical vapor deposition (CVD) approach for the low-temperature synthesis of 27 ultrathin 2DMs. In particular, by mixing BiOCl with selected metal powders to produce volatile intermediates, we show that ultrathin 2DMs can be produced at 280–500 °C, which are ~200–300 °C lower than the temperatures required for salt-assisted CVD processes. In-depth characterizations and theoretical calculations reveal the low-temperature processes promoting 2D growth and the oxygen-inhibited synthetic mechanism ensuring the formation of ultrathin nonlayered 2DMs. We demonstrate that the resulting 2DMs exhibit electrical, magnetic and optoelectronic properties comparable to those of 2DMs grown at much higher temperatures. The general low-temperature preparation of ultrathin 2DMs defines a rich material platform for exploring exotic physics and facile BEOL integration in semiconductor industry.

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2D materials with mixed crystal phase will lead to the nonuniformity of performance and go against the practical application. Therefore, it is of great significance to develop a valid method to synthesize 2D materials with typical stoichiometry. Here, 2D palladium sulfides with centimeter scale and uniform stoichiometric ratio are synthesized via controlling the sulfurization temperature of palladium thin films. The relationship between sulfurization temperature and products is investigated in depth. Besides, the high‐quality 2D PdS2 films are synthesized via sulfurization at the temperature of 450–550 °C, which would be compatible with back‐end‐of‐line processes in semiconductor industry with considering of process temperature. The PdS2 films show an n‐type semiconducting behavior with high mobility of 10.4 cm2 V−1 s−1. The PdS2 photodetector presents a broadband photoresponse from 450 to 1550 nm. These findings provide a reliable way to synthesizing high‐quality and large‐area 2D materials with uniform crystal phase. The result suggests that 2D PdS2 has significant potential in future nanoelectronics and optoelectronic applications.

disturbances and produce very little stray fields, thus allowing for high-density memory integration. [1][2][3] Among them, noncollinear antiferromagnet with nontrivial spin structure has led to unconventional electromagnetic response. [4][5][6][7] When electrical current flows through a non collinear spin texture, the adjacent three spins (S i , S j , and S k ) produce nonzero scalar spin chirality S i • (S j × S k ), can induce nonzero Berry curvature in real space, which acts like a fictitious magnetic field for the conduction electrons and gives rise to the topological Hall effect (THE). [8][9][10][11][12][13][14] There are series of compounds formed between transition or rare earth metals (T) and different main group elements (M) with chemical formula T 5 M 3 . Among them, T 5 Si 3 phases crystallize with the hexagonal Mn 5 Si 3 -type structure (space group P6 3 /mcm) have been found to have complex antiferromagnetic ordering that deserve attention. [15][16][17] In Mn 5 Si 3 -type structure, there are two inequivalent Wyckoff positions of atoms T: 4(d) and 6(g) (T1 and T2, respectively), yielding two structural motifs in the unit cell [18,19] (Figure S1, Antiferromagnets with noncollinear spin order are expected to exhibit unconventional electromagnetic response, such as spin Hall effects, chiral abnormal, quantum Hall effect, and topological Hall effect. Here, 2D thickness-controlled and high-quality Cr 5 Si 3 nanosheets that are compatible with the complementary metal-oxide-semiconductor technology are synthesized by chemical vapor deposition method. The angular dependence of electromagnetic transport properties of Cr 5 Si 3 nanosheets is investigated using a physical property measurement system, and an obvious topological Hall effect (THE) appears at a large tilted magnetic field, which results from the noncollinear magnetic structure of the Cr 5 Si 3 nanosheet. The Cr 5 Si 3 nanosheets exhibit distinct thickness-dependent perpendicular magnetic anisotropy (PMA), and the THE only emerges in the specific thickness range with moderate PMA. This work provides opportunities for exploring fundamental spin-related physical mechanisms of noncollinear antiferromagnet in ultrathin limit.