Table 1. The calculated formation energies of several different vacancies and sulfur, silicon or aluminum doped M-BP, based on Eq. 1 and Eq. 2.

	V1	V1−2	V1−3	V1−4	V1−5	V1−6	V1−8
Vacancies (eV)	2.00	1.60	0.72	1.04	1.48	0.73	2.07
	V1−3−11	V1−2−7	V1−6−9	V1−5−10
	0.68	1.08	1.02	1.01
S-doped (eV)	S1	S1−2	S1−3	S1−4	S1−5	S1−6	S1−8
	0.09	−0.70	−0.64	−0.07	−0.49	−0.05	−0.18
Si-doped (eV)	Si1	Si1−2	Si1−3	Si1−4	Si1−5	Si1−6	Si1−8
	0.70	0.64	0.87	0.69	0.44	0.71	0.23
Al-doped (eV)	Al1	Al1−2	Al1−3	Al1−4	Al1−5	Al1−6	Al1−8
	−1.10	−0.58	−0.44	−1.23	−1.17	−1.21	−0.96